Proceeding

Academic Link Center, University Library Complex
Nishi-Chiba Campus, Chiba University
1-33 Yayoi-cho, Inage-ku, Chiba-shi 263-8522 Japan
August 8 – 9 , 2013

ISBN : 978-4-901404-07-5

Program
SOMIRES 2013 and 231th RISHth

The 20 CEReS International Symposium or The Symposium on Microsatellites for Remote Sensing(SOMIRES 2013) is kick-off event of Chiba University microsatellite project and co-organized by ResearchInstitute for Sustainable Humanosphere (RISH), Kyoto University (The 231th RISH Symposium): The
International Workshop on GPS Radio Occultation Mission with a Microsatellite. This symposium will
provide an opportunity for researchers and system engineers to discuss new and viable technical topics of
microsatellites, payload and spaceborne system, missions, analysis technique and applications for remotesensing.

Organized and Sponsored by Center for Environmental Remote Sensing (CEReS), Chiba University
 Research Institute for Sustainable Humanosphere (RISH), Kyoto University
 Department Electrical and Computer Engineering, Ajou University, Korea.
Contact Persons & Secretary :Contact Persons :Prof. Josaphat Tetuko Sri Sumantyo
Center for Environmental Remote Sensing (CEReS), Chiba University
1-33, Yayoi, Inage, Chiba 263 - 8522 Japan
Phone +81 43 290 3840 Fax +81 43 290 3857
Email : jtetukoss@faculty.chiba-u.jp
Prof. Toshitaka Tsuda
Research Institute for Sustainable Humanosphere (RISH)
Kyoto University, Uji, Kyoto 611-0011, JAPAN
Phone: +81-774-38-3804, FAX: +81-774-31-8463
E-mail: tsuda@rish.kyoto-u.ac.jp
Secretary :Dr. YohandriCenter for Environmental Remote Sensing (CEReS), Chiba University
1-33, Yayoi, Inage, Chiba 263 - 8522 Japan
Phone +81 43 290 3868 Fax +81 43 290 3857
Email : andri_unp@yahoo.com

Collaborators:

Symposium site
Venue
1F, Contents Studio “Hikari”, Academic Link Center, University Library Complex,
Nishi Chiba Campus, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522 Japan.
Maps to access Symposium site: 3-min walk from JR Nishi-Chiba Station to the South Gate of Nishi-Chiba Campus
 7-min walk from Keisei Midoridai Station to the Center Gate of Nishi-Chiba Campus

2Chiba University Map
Nishi-Chiba Campus

3

Contents

ProgramSymposium Site
Contents
Event Schedule

1
2
4
6

Invited Talk
IT01 Development of UAV and microsatellites for remote sensing
IT02 GPS radio occultation measurement technique and its science applications
IT03 Experience from a GPS-RO mission on EQUARS
IT04 Impacts of RO data on rainfall forecasts of heavy rainfalls and typhoon
developments
IT05 Science accommodation for space missions with a focus on radio occultation
sensors and transmitter sources
IT06 A distinct stronger warming in the tropical tropopause layer during 2001-2010
using GPS radio occultation: association with minor volcanic eruptions
IT07 Development of compact plasma instrument（TeNeP）for nano andmicrosatellite
IT08 Elmos constellation: lithosphere, atmosphere and ionosphere monitoring bysmall and microsatellites
IT09 GPS total electron content (TEC) for ionospheric observation
IT10 Ionospheric observations of FORMOSAT-3 and follow-on FORMOSAT-7
IT11 Development of space borne X- band SAR for 100kg satellite
IT12 SAR antenna development in the UK
IT13 Micro SAR satellite development in Korea and a plan of space observation
network in Southeast Asia
IT14 Development of bistatic GPS-SAR image processing algorithm
IT15 UAVSAR development programme in Malaysia
IT16 Hyperspectral camera for microsatellite and UAV
IT17 Modular and compact command & data handling system with fault-tolerant
function for microsatellite
Poster Session
P01 Implementation of CP-SAR signal processing system on virtex-6 FPGA
P02 Monitoring land subsidence by TERRASAR-X in Cengkareng, Jakarta city,
Indonesia
P03 Three-dimensional electromagnetic-field distribution measurement system
P04 Possibilities of approach integrating RS multi-data analysis and GIS for water
resources management and environmental monitoring (the case study of Bili-Biliirrigation system, Indonesia)
P05 Preliminary study of concrete surface temperature mapping on structure
problems in Makassar city with airbone thermal remote sensing
P06 Array of triangular microstrip antenna and combined triple rectangularmicrostrip antenna for radio altimeter and ground penetrating radar

4

9
13
15
17
19
21
23
24
26
27
28
30
32
34
36
37
39

41
43
45
47

49
51

P07
P08
P09

P10
P11

FPGA based multiple preset chirp pulse generator for synthetic aperture radar
onboard unmanned aerial vehicle system
Microwave dielectric constant measurement of arid soil in the 0.3-3 GHz
frequency range and interrelationship with land cover and soil types
The COST-based micro earth sensor(MESA) for small satellite to thesymposium on microsatellites for remote sensing (SOMIRES 2013) and the231th RISH symposium
Allometric modeling for biomass estimation in remote sensing
Doppler Centroid Ambiguity Analysis for High Resolution SAR Imagery
Sensors

5

53
55
57

59
61

Event ScheduleThursday, August 8, 2013
The International Workshop on GPS Radio Occultation Mission with a Microsatellite
09:00 – 09:30

Registration

09:30 – 10:00

Opening Ceremony
Prof. Hiroaki Kuze, Director of CEReS, Chiba University
Prof. Toshitaka Tsuda, Director of RISH, Kyoto University
Prof. Josaphat Tetuko Sri Sumantyo, Microsatellites Project
Photograph Session
Break

Session A1

Moderator : Prof. Josaphat Tetuko Sri Sumantyo

10:00 – 10:30

Development of UAV and Microsatellites for Remote Sensing
Josaphat Tetuko Sri Sumantyo (Chiba University), Koo Voon Chet (MMU Malaysia), and Robertus Heru
Triharjanto (LAPAN Indonesia)

10:30 – 11:15

GPS Radio Occultation Measurement Technique and Its Science Applications

11:15 – 11:35

Experience from a GPS-RO mission on EQUARSBill Kuo and William Schreiner (University Corporation for Atmospheric Research USA)
Toshitaka Tsuda (Kyoto University), Hisao Takahashi(Instituto Nacional de Pesquisas Espaciais), andYuichi Aoyama (National Institute for Polar Research)
11:35 – 12:00

Impacts of RO Data on Rainfall Forecasts of Heavy Rainfalls and Typhoon Developments
Hiromu Seko, Yoshinori Shoji, Masaru Kunii, and Hiromi Owada (Meteorological ResearchInstitute/JAMSTEC)

12:00 – 13:00

Lunch

Session A2

Moderator : Prof. Koh-ichiro Oyama

13:00 – 13:25

Science Accommodation for Space Missions with a focus on Radio Occultation Sensors and Transmitter
Sources
Chris McCormick (Moog), Brian Holz (Golden CO), Dr. Rob Kursinski (Moog), Erin Griggs (Moog)

13:25 – 13:50

A distinct stronger warming in the tropical tropopause layer during 2001-2010 using GPS radio
occultation: Association with minor volcanic eruptions
Sanjay Kumar Mehta (Kyoto University), Masatomo Fujiwara (Hokkaido University), Toshitaka Tsuda(Kyoto University), Jean-Paul Vernier (Science Systems and Applications, USA)

13:50 – 14:15

Electron Temperature Probe (ETP) for Microsatellite
Koh-ichiro Oyama, C. Z. Cheng, Yu-Wei, Hsue (National Cheng Kung University, Taiwan)

Session A3

Moderator : Prof. Katsumi Hattori

14:20 – 14:45

ELMOS Constellation: Lithosphere, Atmosphere and Ionosphere Monitoring by Small and Microsatellites
Tetsuya Kodama (JAXA)

14:45 – 15:10

GPS Total Electron Content (TEC) for Ionospheric Observation
Katsumi Hattori, Shinji Hirooka, Chie Yoshino, (Chiba University) , Yuichi Otsuka(Nagoya University)

15:10 - 15:35

Ionospheric Observations of FORMOSAT-3 and follow-on FORMOSAT-7
Tiger J. Y. Liu (National Space Organization TAIWAN), (National Central University), G. S. Chang, S. J.
Yu, T. Y. Liu (National Space Organization TAIWAN)

15:45 – 16:45

Visit facilities of Center for Environmental Remote Sensing, Chiba University

17:00 – 19:00

Banquet : Corsa Restaurant, Keyaki Kaikan (University Convention Hall), Chiba University

6

Friday, August 9, 2013
Spaceborne SAR Mission
Session B1

Moderator : Dr. Takuji Ebinuma

10:00 – 10:25

Development of Space borne X Band SAR for 100 kg Satellite
Hirobumi Saito, Atsushi Tomiki, Prilando Rizki Akbar (ISAS-JAXA), Takashi Ohtani, Kunitoshi Nishijo(JAXA), Jiro Hirokawa and Makoto Ando (Tokyo Institute of Technology)

10:25 – 10:50

SAR Antenna Development in the UK
Steven Gao (University of Kent), Yohandri and Josaphat Tetuko Sri Sumantyo (Chiba University)

10:50 – 11:15

Korean Microsatellite Mission and VLBI Mission

11:15 – 11:40

Development of Bistatic GPS-SAR Image Processing Algorithm

Tu-Hwan Kim, Dal-guen Lee, Jae-Hyun Kim, Hee-In Yang (Ajou University, Korea)
Takuji Ebinuma and Yoshinori Mikawa (University of Tokyo)
12:00 – 13:00

Lunch

Poster Session
13:00 – 14:00

P01 Implementation of CP-SAR signal processing system on Virtex-6 FPGAKei Iizuka, Kazuteru Namba, Josaphat Tetuko Sri Sumantyo (Chiba University)
P02 Monitoring Land Subsidence by TerraSAR-X in Cengkareng, Jakarta City, Indonesia
Ratih Fitria Putri, Luhur Bayuaji, Josaphat Tetuko Sri Sumantyo and Hiroaki Kuze, (Chiba
University)
P03 Three-dimensional electromagnetic-field distribution measurement system
Satoshi Hasumi (Device Co).
P04 Possibilities of Approach Integrating RS Multi-Data Analysis and GIS for Water Resources
Management and Environmental Monitoring (The case study of Bili-Bili Irrigation System,
Indonesia)
Yaqien Gisno Ogalelano, Takao NAKAGIRI, Hiroki OUE, Dorotea Agnes RAMPISELA, Sartika LABAN(Ehime University)
P05 Preliminary Study of Concrete Surface Temperature Mapping on Structure Problems in Makassar
City with Airbone Thermal Remote Sensing
Arwin Amiruddin(Hasanuddin University), Josaphat Tetuko Sri Sumantyo(Chiba University), Ilham
Alimuddin, Merna Baharuddin (Hasanuddin University)
P06 Array of Triangular Microstrip Antenna and Combined Triple Rectangular Microstrip Antenna forRadio Altimeter and Ground Penetrating Radar
Merna Baharuddin, Elyas Palantei, Zulfajri B. Hasanuddin, Rusli, Andi Azizah (Hasanuddin
University), Josaphat T. Sri Sumantyo (Chiba university)
P07 FPGA Based Multiple Preset Chirp Pulse Generator for Synthetic Aperture Radar Onboard
Unmanned Aerialvehicle System
Kyohei Suto, Josaphat Tetuko Sri Sumantyo (Chiba University), CheawWen Guey, Koo Voon Chet
(MMU)
P08 Microwave dielectric constant measurement of arid soil in the 0.3-3 GHz frequency range andinterrelationship with land cover and soil types
Saeid Gharechelou, Ryutaro Tateishi, Josaphat Tetuko Sri Sumantyo (Chiba University)
P09 The COTS-based Micro Earth Sensor(MESA) for small satelliteto The Symposium on Microsatellites
for Remote Sensing (SOMIRES 2013) and The 231th RISH Symposium
Kazuo Tanimoto, Takanobu Omoto(Meisei Electric), Hiroshi Tachihara(JAXA)
P10 Allometric modeling for biomass estimation in remote sensing
Ali Reza Sharifi and Jalal Amini (University of Tehran)P11 Doppler Centroid Ambiguity Analysis for High Resolution SAR Imagery Sensors
Salar Gharibi and Jalal Amini (University of Tehran)7

Session B2

Moderator : Prof Koo Voon Chet

14:00 – 14:25

UAVSAR Development Programme in Malaysia
Koo Voon Chet (Multimedia University Malaysia), Hean-Teik Chuah (Universiti Tunku Abdul Rahman)

14:25 – 14:50

Hyperspectral Camera for Microsatellite and UAV
Yukihiro Takahashi (Hokkaido University)

14:50 – 15:15

Modular and Compact Command & Data handling System with Fault-Tolerant Function
for Microsatellite
Dae-soo Oh and Myeong -Ryong Nam (JNM Korea)

15:20 – 15:30

Closing Ceremony8

CEReS, Chiba University
RISH, Kyoto University

SOMIRES2013-231th RISH

DEVELOPMENT OF UAV AND MICROSATELLITES FOR REMOTE SENSING
Josaphat Tetuko Sri Sumantyo1), Koo Voon Chet 2), Robertus Heru Triharjanto 3)
1) Center for Environmental Remote Sensing, Chiba University, Japan
2) Faculty of Engineering & Technology, Multimedia University, Malaysia
3) Center for Satellite Technology, Indonesian Aeronautics and Space Agency (LAPAN), Indonesia
ABSTRACT
Synthetic Aperture Radar (SAR) is well-known as a multipurpose sensor in all-weather and day-night time. In thisresearch, we are developing Circularly Polarized Synthetic
Aperture Radar (CP-SAR) onboard microsatellite to observe
land deformation on Earth surface under Japanese Ministryof Education and Technology (MEXT) program etc. The
CP-SAR employs elliptical wave propagation and scattering
phenomenon by radiating and receiving the ellipticallypolarized wave, including the specific polarization as
circular and linear polarizations. The sensor is designed as a
low cost, light, low profile of configuration to transmit andreceive left-handed circular polarization (LHCP) and righthanded circular polarization (RHCP). Then these circularly
polarized waves are employed to investigate relationship ofphysical information of scatterer and axial ratio, ellipticity,tilt angle etc. This sensor is also considered to reduce theeffect of ionosphere’s Faraday rotation. For groundexperiment of CP-SAR, we also develop the CP-SAR
onboard unmanned aerial vehicle (UAV CP-SAR) that is
discussed in this paper.

Fig. 1. Successful first flight of Josaphat Laboratory
Experimental Unmanned Aerial Vehicle (JX-1) at Fujikawa
Airport, Japan on 7 June 2012.

Index Terms— Synthetic Aperture Radar, UAV, CPSAR, microsatellite
1. INTRODUCTION OF CP-SAR MISSION
In this research, we propose Circularly Polarized
Synthetic Aperture Radar (CP-SAR) sensor to retrieve thephysical information of land surface and disaster monitoring.
The sensor is designed as a low cost, light, low profile ofconfiguration to transmit and receive left-handed circularpolarization (LHCP) and right-handed circular polarization(RHCP). For this purpose, we also develop unmanned aerial
vehicle (UAV) for ground experiment of this sensor [1]-[2],see Fig. 1 and Fig. 2.
The main mission of CP-SAR is to hold the basic
research on elliptically polarized scattering and its
applications. In the basic research, we will investigate theelliptical (including circular and linear polarizations)Fig. 2. Structure of Josaphat Laboratory Experimental
Unmanned Aerial Vehicle (JX-1)

9

Copyright © 2013 by CEReSCEReS, Chiba University
RISH, Kyoto University

SOMIRES2013-231th RISH

TABLE I. SPECIFICATION OF UAV CP-SAR
UAV CP-SAR

Parameter

Tx: RHCP

1 to 4 km
1270 MHz  150 MHz

Baseband range

Polarization

DC to 150 MHz
50 W, Pulse width 10 s (max),
Duty circle 2% (max)TX & RX : RHCP+LHCP

Transmission system gain

+ 47 dB (min)Pulse transmission output power

Rx : LHCP
Rx : RHCP

Value

AltitudeFrequency range

Receiver system gain

+ 60 dB (min)Gain flatness

 1.5 dB (max)Receiver noise ratio

3.5 dB (max) @+25oC

Modulator(RX and TX) QPSK

Output higher harmonic wave

-30 dBc (max)

Output spurious-60 dBc (max)Transmission system gain tuning
1/2/3/8/16 dB (0 to -31 dB)
function
Receiver system gain tuning function 1/2/3/8/16 dB x 2 (0 to -62 dB)

Fig. 3. Principle of CP-SAR sensor onboard UAV
scattering wave from the land surface, generation of axial
ratio image, ellipticity and tilted angle images etc. We willhold the analysis and experiment of circularly polarizedwave scattering on vegetation, snow, ice, soil, rock, sand,grass etc to investigate the elliptical scattering wave. These
images will be extracted by using the received RHCP and
LHCP wave. The principle of CP-SAR onboard UAV(UAV CP-SAR) is shown in see Fig. 3. This figure shows
CP-SAR sensor transmits only one polarization, RHCP or
LCHP, then this sensor will receive RHCP and LHCP
scattering waves simultaneously. Then this image is
employed to investigate the relationship of CP waves andphysical characteristics of vegetation, soils, snow etc. The
image of tilted angle as the response of land surface also
will be extracted to mapping the physical information of thesurface, i.e. geological matters, contour, tree trunk structure
and its characteristics, snow-ice classification, vegetation
characteristics etc.
In the application development, CP-SAR sensor will be
implemented for land cover mapping, disaster monitoring,
Cryosphere monitoring, oceanographic monitoring etc.
Especially, land cover mapping will classify the forest andnon-forest area, estimation of tree trunk height, mangrove
area monitoring, Arctic and Antarctic environment
monitoring etc. In disaster monitoring, CP-SAR sensor will
be employed for monitoring of earthquake area, volcano
activity, landslide etc. Especially, this L band CP-SAR
sensor for UAV is being developed in our laboratory underJapan - Malaysia joint project (JICA-JST ODA program) in2011 to 2014 to monitor landslide at Malay Peninsula andSoutheast Asian countries in the future.

Impedance

50 Transmission system output VSWR 1.5 : 1 (typ.)
Receiver system input VSWR
Transmission system antenna
switching speed
Receiver system antenna switching
speed
Transmission system On/Off speed
Receiver system On/Off speed

1.5 : 1 (typ)1s (typ.) / 2 s (max)1s (typ.) / 2 s (max)
100 ns (max)Current consumption

100 ns (max)DC +28 V (DC +25 to + 35 V
switchable)
5A (max)

Temperature+0oC to 45oC

Saving temperature-20oC to 80oC

RF connector

SMA-Female

Power connector

N/MS3102A10SL-3P

Power voltage

Control connector

D-Sub-37P

Weight10 kg (max)
W250mm x H100mm xD300mm4.33 up to 47.63 s

Size
Pulse Length
Off Nadir30 up to 60

Resolution

Up to 1 m

Swath Width

1 km

Antenna Size

0.75 x 0.2 m (4 panels)

Axial Ratio

3 dB

Antenna Gain

14.32 dBic

for controlling all sub-systems in UAV CP-SAR. Telemetry
and Command Data Handling subsystems use S-bandcommunications between UAV and ground station. Attitude
Controller is composed by Inertial Measurement Unit
(IMU) and four GPS units. Sensors are composed by CPSAR as main mission sensor, and other sensors. CP-SAR
sub-system itself is composed by chirp pulse generator
module, Transmitter and Receiver (Tx-Rx) module, andImage Signal Processing module. Fig. 4 shows block

2. CP-SAR SYSTEMThe UAV CP-SAR (Fig. 1 and Fig. 4) is mainly composedby Flight Control System, Onboard Computer, Telemetry
and Command Data Handling, Attitude Controller, andSensors. Flight Control System is composed by manual andautomatic flight module. Onboard Computer is employed10

Copyright © 2013 by CEReSCEReS, Chiba University
RISH, Kyoto University

SOMIRES2013-231th RISH

diagram of UAV CP-SAR that composed by UAV segment,
ground station 1 and 2 segments. Especially, CP-SAR ismainly composed by RF system, chirp pulse generator, andimage processing systems. Ground control segment has twounits, where unit 1 for CP-SAR sensor monitoring andimage processing. Unit 2 is employed for flight control andweather monitoring.
Fig. 5 shows the circuit of RF system or Tx-Rx moduleof CP-SAR. This system is composed by transmitter andreceiver sub modules. The input of transmitter is In-phase(I) and Quadrature (Q) signal of chirp pulse generated bypulse generator with baseband range is DC to 150 MHz(normally 50 MHz). Then chirp pulse is modulated byfrequency 1,270 MHz, where our Tx-Rx system has
frequency range 1270 MHz ± 50 MHz (maximum ± 150
MHz). The transmission system has gain tuning function as
1, 2, 3, 8, 16 dB or 0 to -31 dB, and receiver has gain tuning
function as 1, 2, 3, 8 and 16 x 2 or 0 to -62 dB. Poweramplifier (PA) is available to control pulse transmission
output power 50 W with pulse width maximum 10 s, andmaximum duty circle is 2%. The switching speed oftransmission and receiver system antennas (RHCP and
LHCP) is typically 1 s and maximum 2 s. The antenna iscomposed by two sets of CP microstrip array antenna(LHCP and RHCP panels), totally 4 panels to realize fullpolarimetric CP-SAR sensor. Size of Tx and Rx unit is
W250 mm x H100 mm x D300 mm as one module in our
CP-SAR system as shown in Fig. 4(b)-(c).
Fig. 5(d) shows our chirp pulse generator and image
processing module. For the experiment, we could control
the pulse length and bandwidth of chirp pulse (max 150
MHz). We save the data to SSD memory. We also plan tohold onboard processing for emergency mode and save raw
data. Fig. 5(e) shows output of chirp pulse generator withbandwidth 50 MHz with center frequency 1.27 GHz.

Fig. 4. Block diagram of UAV CP-SAR system
Transmitter (Tx)

I
Q

RHCP
LHCP

I
Receiver (Rx): RHCP

Q

C
I
Receiver (Rx): LHCP

Q

(a)
(b)

(c)

(d)

(e)

3. CP-SAR ONBOARD UNMANNED AERIALVEHICLE SYSTEM
In this research, the UAV CP-SAR as shown in Fig. 1 isdeveloped for ground testing of CP-SAR. The platform
called Josaphat Laboratory Experimental UAV (JX-1) has
25 kg of payload availability for various microwave sensors(CP-SAR, GPS-SAR etc) and optic sensors, i.e. hyper
spectral camera. The operation altitude is 1,000 m to 4,000
m. The specification of CP-SAR sensor for UAV is center
frequency 1,270 MHz, ground resolution up to 1 m, pulse
length could be tuned from 4.5 to 48 s, maximum pulse
bandwidth 150 MHz, off nadir angle 30o to 60o, swath width
1 km, antenna size for 4 panels of CP-SAR 1.5 m x 0.4 m,
PRF 1,000 Hz, and peak power 8.65 W (1 km) to 95 W (4km). We plan to hold ground experiment with altitude lessthan 2 km with pulse transmission output power 50 W. The
CP-SAR has receiver antenna composed by LHCP and

10 s

50 MHzFig. 5. (a) Block diagram of RF system, (b)-(c) RF system,(d) Signal Processing Module, and (e) Chirp pulse output
RHCP antenna. The data retrieved by LHCP and RHCP
antenna [3] is employed to investigate the characteristics ofelliptical polarization, including circular and linear
polarizations.

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Copyright © 2013 by CEReSCEReS, Chiba University
RISH, Kyoto University

SOMIRES2013-231th RISH

TABLE II. SPECIFICATION OF CP-SAR ONBOARD
MICROSATELLITE
Parameters
Values

HH

HV

VH

VV

LL

LR

RL

RR

AltitudeFrequency
Pulse length
Chirp bandwidth
Off Nadir Angle
Time Margin
Duty Cycle Maximum
Receiver Temperature
Antenna Length
Antenna Width
Operational PRF
Noise Figure
Normalized backscattering coefficient
Antenna Efficiency Loss
Single Antenna Panel Size
Transmit Peak Power
Average PowerOperational Duty Cycle
Operational Ground Swath Width
Swath Width Time
Inclination angle
Range Resolution
Ground Resolution
Azimuth Resolution
Elevation Antenna Beamwidth
Antenna Gain

Fig.6. Images of linear and circular polarization

550 km1.27 GHz
30 s
10 MHz30 degrees
30 ms
10%
300 K
6.0 m
1.8 m
1950 ~ 1880 Hz
3 dB-25 dB
2 dB
500 x 500 x 3 mm
687 Watts
39 Watts
5.85%
67.08 km
230 / 240 / 240 s
97.591 degrees
15 m
30 m
3m
4.8 degrees
33.86 dB

ACKNOWLEDGEMENT
Thank to Japanese Ministry of Education and Technology(MEXT) for Integrated Earth Environment Diagnosis
Program, JICA-JST ODA Program for Malaysia Peninsula
landslide monitoring program, and Indonesian Aeronautics
and Space Agency (LAPAN) for LAPAN-Chibasat program.

Fig.7. Illustration of CP-SAR onboard microsatellite
We have simulated circularly polarized waves with fullpolarization (LL, LR, RL and RR) as shown in Fig. 6 byusing ALOS PALSAR polarimetric mode images. Where L
and R is left handed circular polarization and right handed
circular polarization, respectively. LR means LHCP
transmission and RHCP receiving. In the future, further
investigation of characteristics of circular polarization will
be done by using our CP-SAR onboard UAV andmicrosatellite called LAPAN-Chibasat as shown on Fig. 7.

REFERENCES[1]J.T. Sri Sumantyo, "Microwave Remote Sensing
Research and Education at Center for Environmental
Remote Sensing, Chiba University," IEEE Geoscienceand Remote Sensing Society (GRSS) Newsletter, Issue#159, pp. 32-38, June 2011.
[2] J.T. Sri Sumantyo, Chapter 11. Circularly Polarized
Synthetic Aperture Radar onboard Unmanned Aerial
Vehicle (CP-SAR UAV), Autonomous Control Systems
and Vehicles, Kenzo Nonami edn., Springer, December
2012.
[3] Yohandri, V. Wissan, I. Firmansyah, P. Rizki Akbar, J.T.
Sri Sumantyo, and H. Kuze, "Development of Circularly
Polarized Array Antenna for Synthetic Aperture Radar
Sensor Installed on UAV," Progress in Electromagnetics
Research C, Vol. 19, pp. 119-133, January 2011.

4. SUMMARY
In this paper, we introduce the progress of UAV
development for ground experiment to investigate
performance of our CP-SAR sensor. The CP-SAR isdesigned as small, light in weight and low power
consumption system. The CP-SAR sensor is developed toradiate and receive elliptically polarized wave, including
circularly and linearly polarized waves. In the near future,
this sensor will be installed in our UAV and microsatellitethat will be applicable for land cover mapping and disastermonitoring.

12

Copyright © 2013 by CEReSCEReS, Chiba University
RISH, Kyoto University

SOMIRES2013-231th RISH

GPS Radio Occultation Measurement Technique and
Its Science Applications
Ying-Hwa Kuo1 and William Schreiner
University Corporation for Atmospheric Research
1
Email: kuo@ucar.edu
Abstract
The atmospheric limb sounding technique making use of radio signals transmitted by the Global Positioning
System (GPS) satellites has emerged as a powerful and relatively inexpensive global observing system in all
weather. As demonstrated by the proof-of-concept GPS Meteorology (GPS/MET) experiment and later by the
CHAMP and SAC-C missions, the GPS radio occultation (RO) sounding data are shown to be of high accuracy
and high vertical resolution. The GPS RO data provided by the joint U.S.-Taiwan COSMIC/FORMOSAT-3
mission, a constellation of six microsatellites launched in April 2006, have been shown to be extremely valuable
for global numerical weather prediction, climate monitoring, and space weather forecasting. In this paper, we
discuss the basic measurement technique of GPS radio occultation. We present the applications of RO data inweather, climate and space weather, based on the results from the COSMIC mission. We also discuss thedevelopment of the follow-on mission, COSMIC-2, which is expected to have an even greater impact on researchand operation.
Keywords: microsatellite, GPS, radio occultation, COSMIC
1. Introduction
The radio occultation (RO) technique, which makes use ofradio signals transmitted by Global Position System (GPS)satellites, has emerged as a powerful and relatively
inexpensive approach to sounding the global atmospherewith high precision, accuracy and vertical resolution in all
weather, and the data are distributed uniformly over bothland and ocean. This was first demonstrated by theproof-of-concept GPS/MET (GPS Meteorology) experimentin 1995-1997 (Ware et al. 1996), and further substantiated by
the CHAMP (CHAllenging Minisatellite Payload, Wickert etal. 2001) and the SAC-C (Satellite de Aplicaciones
Cientificas-C, Hajj et al. 2004) missions. In April 2006, theFormosa Satellite Mission #3/Constellation Observing
System for Meteorology, Ionosphere and Climate(FORMOSAT-3/COSMIC, hereafter referred to as
COSMIC) was successfully launched into initial orbits of
512 km from the Vandenberg Air Force Base. Within a year,
the six COSMIC satellites are deployed to its final orbit of
800km. Anthes et al. (2008) summarized the early results of
COSMIC mission. As of July 2013, COSMIC has produced
3.8 M GPS RO soundings, which have significant impact on
operational weather prediction, climate monitoring, andspace weather forecasting. Even though COSMIC has a
mission life of five year, five out of the six microsatellites arestill operating, producing 1,500 – 2,000 GPS RO soundings
per day to support research and operation.

Fig. 1. The number of COSMIC GPS RO soundings
since launch. Red color indicates number of real-timesoundings per day, and green color indicates numberof soundings after post-processing.
2. Radio Occultation Technique
The GPS RO measurements are based on the phase delay
of GPS radio waves transmitted from a GPS satellite
occulted behind the Earth as viewed from a
low-Earth-orbiting satellite. The magnitude of the delay isrelated to the electron density in the ionosphere and thedensity of the neutral atmosphere. By tracking the signals
transmitted from GPS we can obtain vertical profiles ofbending angles, which can be used to retrieve information onelectron density, atmosphere refractivity, temperature andwater vapor (Kursinski et al. 1997).

13

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SOMIRES2013-231th RISH

Fig. 2. Schematic diagram illustrating the GPS
RO measurement technique.

4. Summary
With the continued operation of COSMIC through at least
2016 and the execution of the COSMIC-2 mission beginningwith a first launch in early 2016 and a second launch in 2018,
radio occultation data will continue to be freely available tosupport research and operations for many more years tocome. With nearly an order of magnitude more RO data ofhigher quality expected to be available from COSMIC-2,
unprecedented research opportunities will open up forweather, climate and space weather research, and the impact
on operational NWP forecasting will be increased over thepresent, already significant, impact of COSMIC data (Anthes2011).

3. COSMIC-2 Mission
Building upon the success of COSMIC, U.S. agencies andTaiwan are developing a follow-on RO mission (called
FORMOSAT-7/COSMIC-2) that will launch six satellites
into low-inclination (Equatorial) orbits in early 2016, andanother six satellites into high-inclination (polar) orbits inearly 2018. U.S. agencies, led by the National Oceanic andAtmospheric Administration (NOAA) and the U.S. Air
Force and including NASA and NSF, are partnering with
Taiwan's National Space Organization (NSPO) to execute
the COSMIC-2 program. In comparison with the original
COSMIC mission, COSMIC-2 will have several important
advances. First, it will use the latest generation receiver,
known as TriG, developed by the Jet Propulsion Laboratory(JPL), which can track radio signals from three global
satellite navigation systems, including GPS (U.S.),GALILEO (Europe), and GLONASS (Russia). Second, anadvanced antenna design will considerably boost theperformance of radio signal tracking, resulting inconsiderably improved quality of radio occultation sounding.
Third, through both tropical and polar constellation,
COSMIC-2 will collectively produce more than 10,000 radio
occultation soundings per day.

References
Anthes, R. A. and Coauthors (2008): The
COSMIC/FORMOSAT-3 Mission: Early results.
Bull. Amer. Meteor. Soc., 89, 313-333.
Anthes, R. A., 2011: Exploring earth's atmosphere withradio occultation: Contributions to weather, climate andspace weather. Atmospheric Measurement Techniques,4, 1077-1103, DOI: 10.5194/amt-4-1077-2011.
Hajj, G., and Coauthors, 2004: CHAMP and SAC-C
atmospheric occultation results and intercomparisons, J.
Geophys.Res.,109,
D06109,doi:10.1029/2003JD003909.
Kursinski, E. R., G. A. Hajj, S. T. Schofield, R. P. Linfield,
and K. R. Hardy, 1997: Observing Earth’s atmospherewith radio occultation measurements using the Global
Positioning System. J. Geophys. Res., 102,23429-23465.
Ware, R., and Coauthors 1996: GPS sounding of theatmosphere from low Earth orbit: Preliminary results.
Bull. Amer. Meteor. Soc., 77, 19-40.
Wickert, J., and Coauthors, 2001: Atmosphere sounding by
GPS radio occultation: First results from CHAMP.
Geophys. Res. Lett., 28(17), 3263-3266Fig. 3. Global coverage of COSMIC-2 soundings
in one day shown in green.

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SOMIRES2013-231th RISH

Experience from a GPS-RO Mission on EQUARS
Toshitaka Tsuda1, Hisao Takahashi2, and Yuichi Aoyama3
1

Research Institute for Sustainable Humanosphere (RISH), Kyoto University,
2
Instituto Nacional de Pesquisas Espaciais (INPE), Brazil,
2
National Institute for Polar Research (NIPR),
tsuda@rish.kyoto-u.ac.jp

Abstract
In collaboration with INPE, we promoted a project on GPS radio occultation, aiming as a launch of a small LEO
satellite named EQUARS (Equatorial Upper Atmosphere Research Satellite) in 2000s. We basically completed
design of the satellite together with antenna and receiver system for the GPS RO mission. EQUARS was alsoplanned to carry several sensors for optical airglow, in-situ measurements of ionospheric electron density, andplasma parameters. However, unfortunately, INPE has suspended the whole plan of EQUARS, whose launch
was originally planned in 2006. We introduce here outline of the GPS RO mission proposed for EQUAS.
2. GPS-RO on EQUARSFor observations of atmospheric and ionosphericcharacteristics, the Brazilian space agency (INPE)
announced a plan of a small LEO satellite named EQUARS(Equatorial Atmosphere Research Satellite). Then, we
proposed a GPS RO measurement on EQUARS. Inclination
angle of the EQUARS orbit was less than 20o so it canobtain a dense data-set of temperature, humidity and electron
density in the equatorial atmosphere. GPS-RO data are also
useful to improve weather forecast at low latitudes through areal-time assimilation for a numerical weather prediction
model.

1. Background of GPS-RO Mission
From our recent knowledge of dynamical processes inthe Earth’s atmosphere, it is well known that the equatorial
atmosphere plays an important role with respect to energy
sources, transport, and global circulation. Atmosphericwaves, such as gravity waves, tides and equatorial waves,generated in the tropical troposphere, play a significant partin transportation of wave energy and momentum flux to the
middle atmosphere and ionosphere. Deposition of
momentum and energy in the upper atmosphere drives thegeneral circulation of the middle atmosphere. Gravity waves
trigger ionospheric disturbances (Plasma bubbles). It is only
in recent years that an integrated picture of the energybalance of the middle and upper atmosphere is beginning toemerge.
One of our special interests is to understand the
dynamical and plasma characteristics of the equatorial
atmosphere over Indonesia, South America and Africa
where land-sea-ocean interactions are most active in theworld. Plasma bubbles in the ionosphere directly affectsatellite telecommunications. Changes in the global scale
circulation of the lower atmosphere, such as those associatedwith El Niño and La Niña, greatly affect the climate not onlyin the tropics but also regions at middle and high latitudes.
Recent GPS RO mission; GPS/MET, CHAMP, SAC-C,
GRACE, COSMIC, METOP, etc, have provided us a great
opportunity to understand a global picture of the atmosphere
dynamics and ionosphere irregularities. Further observations
with more GPS RO missions are needed. For this reason we
encourage the GPS-RO mission promoted by CEReS of
Chiba University.

GPS Occultation measurements by LEO Satellites,
COSMIC and EQUARSEQUARS
1 sat.

GPS
24 sats.

COSMIC
6 sats.

GPS occultation data
20-40MB/day

IGS

Brazil
INPE(International GPS
Service)
Level 0Real Time

Level 0Real Time

Taiwan & USA (UCAR)CDAAC

GPS reference data
at ground fiducial
sites(COSMIC Data Analysis
and Archive Center)

Real Time

NASA/JPLRASC

Data assimilation

Off-line

Atmospheric Research

NCEP

Figure 1 Data acquisition, transfer and analysis system for
GPS RO mission of EQAURS
Figure 1 shows our proposal for a data transfer andanalysis system of GPS occultation data that was considered
for EQUARS. Raw data will be down-loaded to the15

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Brazilian ground station at Natal (7S, 60W), which, however,misses some orbits in the case that the inclination angle of
EQUARS is larger than about 15 degrees. For a real-timedata transfer, we needed to find another ground-based
tracking station in the East Asia, such as Biak in Indonesia,
Darwin in Northern Australia, and Bangalore in India.
We planned to transfer the Level-0 to Japan (RASC) ona real-time basis. The data was also planned to transfer to
CDAAC at UCAR for distribution to a wider user
community, including meteorological agencies for data
assimilation into a numerical weather prediction model.
It is necessary for CEReS to establish a similar datatransfer and analysis system for the new LEO experiment.
GPS RO data is most useful when they are processed on areal-time basis and transferred to a meteorological agency
with latency not longer than a few hours.

3. Antenna Design for EQUARSFor a GPS RO mission, two types of antennas arenormally installed on a LEO satellite. One antenna with ahigh-gain (about 15 dB) is attached on the side panel of asatellite in the orbit direction. And, it is pointed about
20-25 degrees downward so as to observe limb of the
Earth. The other antenna can be a small omnidirectional
one for conventional positioning. Two sets of the antenna
pairs could be installed on the fore and rear sides of the
LEO satellite in order to measure both rising and setting
occultation events. Figure 2 shows two examples of theoccultation antenna that were considered for EQUARS;
phased array with patched antenna and a high-gain
antenna.

(a)(b)

Heli-bowl
antennaFigure 2 Two examples of antenna for occultation. (a) A
phased array consisting of four micro-strip patch panels.
Although the antenna is attached to the satellite, antenna
core-sight is tilted about 20-30 degrees downward relative
to the satellite orbit for pointing toward limb of the Earth.
(b) a heli-bowl antenna with high-gain, which was used
for CHAMP.

4. Summary
GPS RO data is useful not only for atmospheric sciencebut also operational meteorology. GPS RO mission needs a
careful design for both instruments/firmware on board asatellite and ground-based data analysis system. We hope the
new GPS-RO experiment promoted by CEReS will be
successful by obtaining intensive supports from international
community.

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SOMIRES2013-231th RISH

Impacts of RO Data on Rainfall Forecasts of Heavy Rainfalls and Typhoon Developments
Hiromu Seko1, Yoshinori Shoji2, Masaru Kunii2, and Hiromi Owada3
1
Meteorological Research Institute/JAMSTEC, 2Meteorological Research Institute,3
Numerical Prediction Division/Japan Meteorological Agency, E-mail hseko@mri-jma.go.jp
Abstract
Radio waves (RWs) that are transmitted from satellites of the Global Navigation Satellite System (GNSS) aredelayed and bent by atmosphere in which the paths of the RWs pass before reaching low earth orbit (LEO)
satellites. In radio occultation (RO) observations of GNSS satellites, information of water vapor and temperature
is obtained from the bending angle or delay of the RWs. In this presentation, the results of data assimilation (DA)experiments of GNSS RO data in the Meteorological Research Institute (MRI) and the recent usage progress of
GNSS RO data in the operational global DA system of the Japan Meteorological Agency (JMA) are explained.
Keywords : Radio Occultation, Data Assimilation, Rainfall Forecast, Heavy Rainfall.
the shape of the rainfall region became similar to theobserved one. However, the reproduced rainfall amountremained smaller than the observed one. When the RO data
were assimilated, the low-level water vapor was increased sothat the rainfall amount was largely increased. When PWV
and RO data were assimilated simultaneously, low-level
water vapor in the rainfall region and on its southern side wasincreased, and then shapes of rainfall region and the rainfall
amount became similar to the observed ones.
RO data was also used to investigate impacts on thedevelopment of a tropical cyclone (TC), ‘Usagi’ that
occurred in July 2007 (Kunii et al., 2012). Impacts of the RO
refractivity are compared against the JMA’s global analysis(GA) by conducting forecasts using the JMA non-hydrostatic
model (Fig. 5). When the GA was used for the initial field, no
typhoon was formed in the forecast model. In contrast, when
the GA was replaced by the Meso-4DVar analysis (MA), thegeneration of the TC was successfully simulated. When RO
data was assimilated, the intensity forecast was significantly
improved (MA_RO). The results indicate that RO data isbeneficial for the TC forecast.

1. Introduction
In the Japan, humid airflows supplied from the sea oftencause heavy rainfalls. Middle-level dry layers also enhance
heavy rainfalls, because they increase convective instability.
Thus, water vapor distribution over the sea and its verticalprofiles are needed to increase accuracy of the numerical
forecasts. Global Navigation Satellite System (GNSS) radio
occultation (RO) data were used as data assimilation (DA)data because it provides vertical profiles of refractivity. To
show the impact of the RO data on the numerical forecasts, it
was applied to events of heavy rainfalls and typhoons. Apartfrom RO, ground-based GNSS data, such as precipitablewater vapor (PWV) or slant water vapor (SWV) (Fig. 1), arealso expected to improve water vapor distributions in theanalyzed fields. To show synergy effects of RO andground-based GNSS data, simultaneous assimilations ofthese data was also performed. RO data was also expected to
be a useful data that improves temperature distributions. The'Yamase' phenomenon, in which cold airflows cause stratus
clouds east of the northern Japan, was also adopted as atarget of RO DA experiments.
2. Data assimilation experiments of RO data
DA methods of RO data and PWV, SWV have beendeveloped so far (Seko et al., 2010; Seko et al., 2004), andtheir impacts on rainfall forecasts were investigated with the
Mesoscale 4-dimensional Variational DA system (Meso4DVar) of the Japan Meteorological Agency (JMA). Thesemethods were applied to a heavy rainfall that occurred at thenorthern Japan on 16 July 2004 (Seko et al., 2010). Figures
2-4 show the distributions of predicted rainfall regions andincrements of the analyzed water vapor fields. When PWVdata were assimilated, water vapor in the rainfall region wasincreased and on the northern sides was decreased, and thenFig. 1. Schematic illustrations of the observation operatorsof (a) PWV and SWV, and (b) RO data. Thick solid andbroken lines indicate actual topography and model
topography, respectively.

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Third target is a cold weather (Yamase) insummer over the northeastern Japan, which is
produced by a cool polar maritime air mass thatdevelops over the North Pacific, including theBering Sea and the Sea of Okhotsk. It usuallyaccompanies boundary layer clouds (Yamase
clouds) on east of the northern Japan. Yamasealso influences the agricultural crops. It isneeded to predict Yamase accurately. In thisstudy, RO data was assimilated by the nested
Local Ensemble Transform Kalman Filter(LETKF) system (Miyoshi and Aranami, 2006).
When conventional data of the JMA wasassimilated by the LETKF system, Yamase
clouds were reproduced in all of the ensemble
members. However, impacts of RO data on the
Yamase clouds remained relatively small
because the positions of RO data were far fromthe Yamase clouds. The number of Yamase
events to which RO assimilation experiments
are applied should be increased inorder to show the impact of RO data
more clearly.

SOMIRES2013-231th RISH(b) PWV(a) RO(c) SWV

(mm)
(m/s)

(mm)

Fig.2 Reproduced 3-hour rainfall of forecast time from 0 to 3 hours reproduced
from the analyzed fields. Valid time is 15 to 18 JST 16 July 2004.
2.0(c) SWV(b) PWV(a) RO
1.5
1.0
0.5
0.1
-0.1
-0.5
-1.0
-1.5
-2.0
7.5(m/s)(g/kg)

Fig.3 Horizontal distributions of the difference of water vapor from ‘CNTL’ at theheight of 21 m. Black lines indicate the position of the vertical cross sections ofFig. 4.
2.0(c) SWV(b) PWV(a) RO
1.5
10

10

10

8

8

8

1.0

6

6

6

0.1
-0.1

4

4

4

-0.5

2

2

2

-1.0
-1.5
-2.0
(g/kg)

0.5

32

34

36

38

40

42N
Latitude

32

34

36

38

40

42N
Latitude

32

34

36

38

40

42N
Latitude10(m/s)Fig.4 Vertical distribution of the difference of water vapor from ‘CNTL’ at thelatitude of 138 deg. Vectors represent horizontal wind direction and velocity.

3. Recent usage progress of RO
data in the operational global DA
system of the JMA
The JMA began assimilating RO Fig.5 Distributions of sea-level pressure (contour, hPa), surface wind (vector, ms-1), and 3 hrefractivity data into its operational
accumulated precipitation (color, mm) at 1800 UTC 29 July 2007 predicted by NHM using
different initial fields. (a) GA, (b) MA, and (c) MA _RO.
global NWP system on March 22,
2007, and revisions to this process
The Meso-4DVar system was developed by the Numericalwere implemented in the system on December 18, 2012. A
Prediction Division of the JMA.
bias correction procedure had been implemented in the
preprocessing of RO data due to the presence of systematic References
biases in the tropical and polar regions (Owada et al. 2012). 1) Kunii, M., H. Seko, M. Ueno, Y. Shoji, and T. Tsuda, Impact ofAssimilation of GPS Radio Occultation Refractivity on the Forecast
As the biases were reduced via updates of the observationof Typhoon Usagi in 2007, J. Met. Soc. Japan, 90, 255-273 (2012).
operators, the correction procedure was eliminated. 2) Miyoshi, T., and K. Aranami, Applying a Four-dimensional Local
Observation system experiments for the new assimilation
Ensemble Transform Kalman Filter (4D-LETKF) to the JMA
configuration, which includes these updates, showed that
Nonhydrostatic Model (NHM), SOLA, 2, 128-131 (2006).
analyses and forecasting of temperature and sea surface 3) Owada, H., and K. Yoshimoto, Recent Updates on the Usage of
GNSS RO Data in JMA's Operational Global Data Assimilationpressure were improved, especially in the Southern
System, CAS/JSC WGNE Res. Activ. Atmos. Oceanic Modell. 42,
Hemisphere. Most of the improvements were brought about
1-11 (2012).
by the observation operator updates.
4) Seko, H., M. Kunii, Y. Shoji, and K. Saito, Improvement of Rainfall
Forecast by Assimilations of Ground- Based GPS Data and Radio
Occultation Data, SOLA, 6, 33-36 (2010).
5) Seko, H., T. Kawabata, T. Tsuyuki, H. Nakamura, and K. Koizumi,
Impacts of GPS-derived Water Vapor and Radial Wind Measured
by Doppler Radar on Numerical Prediction of Precipitation. J. Met.
Soc. Japan, 82, 473-489 (2004).

Acknowledgements
The CHAMP data and ground-based GPS data were provided
from the GFZ and GSI. The COSMIC refractivity we used was
calculated at the COSMIC Data Analysis and Archive Center.

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SOMIRES2013-231th RISH

Science Accommodation for Space Missions with a focus on
Radio Occultation Sensors and Transmitter Sources
For
The Symposium on Microsatellites for Remote Sensing (SOMIRES 2013) and
The 231th RISH Symposium
Chris McCormick1, Brian Holz2, Dr. Rob Kursinski1, Erin Griggs1
1
Moog, Golden CO, 2O3B Networks
Abstract
Science Accommodation and Science Instrument hosting from a space mission and space resources design “Total
Systems & Science Engineering” perspective. This paper will present a short end-to-end science coordination
mission, along with first introduction of the Ka-Band occulting system in the planning stages using the newly
launched O3B Networks medium Earth Orbit equatorial communication spacecraft as the Ka Band source.
spacecraft, or alternately with Inmarsat. Standard ground
1. Introduction
Radio Occultation has been used on many of the planets to stations can be used to collect the resultant occultation datadate, generally at higher frequencies than L-Band, in the S- to for store and forward methods.
Ka-Bands (2.3 to 30+ GHz). General RO methods at Earth,has been used with the L-Band due to the prominence of„free‟ transmitters with the GNSS systems. An extension ofthis method into the Ka-Bands (~20 GHz) on a newer system
launched in 2013 system is described. The information to bepresented is twofold, one on the mission and payload
description for Ka-Band radio occultation, and two, on theprocess of designing spacecraft for science missions, withthis Ka-Band mission being the example.

2. Methods
The O3B satellites are orbiting roughly 8000 km altitude
over the equator with coverage ~ +/-45 degrees of Latitude,
see Figure 1. There are 12 satellites in the first
constellation, with a plan for a total of 24; with 4 in orbit now,and 4 more launching September 2013. The downlink
frequencies that are available are mostly from 17.8 to 19.3
GHz with some higher to 20.2 GHz. It is possible for theirsatellites to have some of their dishes pointing at the Earth
Limb. These would transmit two or more pure carrier
frequencies to use for occulting signal reception. The
antennas on the O3B spacecraft are approximately 30 cm,
and at 19 GHz, that is 44 dB of gain, and ~ 3 degree beamwidth. See Figure 2. For the receiver spacecraft, we canhave larger antennas if desired, but a 30 cm one is used foranalysis, both from the science perspective, and for its impact
on pointing requirements and platform stability requirements
levied on the spacecraft design.
The Receiving spacecraft orbits will be modeled after the
COSMIC system, though with 12 to 24 spacecraft in 72
degrees inclination and 800 km circular orbits. Real timecommunications can also be performed with the O3B

19

Fig. 1 Occulting Coverage in Ka-Band (1)Figure 2. Spacecraft steerable spot beams (1)3. Results and Discussion
Results will be shown for Occulting statistics if Ka
band receivers were on board 12 to 24 higher inclination
satellites, with a discussion of similar data products with

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higher energy carriers and shorter wavelengths of ~1.6 cm
plausible for ingestion into forecasting models. Figure 3
below are estimate of standard deviation of water vapor error
for clear sky tropical profile retrieved tracking four O3B
signals at 17.8, 18.6, 19.3 and 20.2 GHz.

Remote Sensing (CEReS), Chiba University and ResearchInstitute for Sustainable Humanosphere (RISH), Kyoto
University.

References
1) O3B Networks, www.o3bnetworks.com
2) Moog, www.Moog.com
Contacts
1) Chris McCormick; cmccormick@moog.com
2) Rob Kursinski; rkursinski@moog.com

Figure 3 Tropical water vapor error (2)Suggestions and first level design constraints are also
shown for hosting occulting receivers at these frequencies,
and their proposed antenna design gain patterns andpointing control. Spacecraft accommodation systemengineering is addressed and interactions of the classicalspacecraft subsystem trades are presented, for spacecraft
and instrument for GNSS-RO and Ka-RO for spacecraft
such as depicted in Figure 4.

Figure 4 – GNSS & Ka Radio Occultation spacecraft
concept (2)4. Summary
Radio Occultation information content is not restricted to
GNSS-RO; and should be investigated in most allavailable stable frequency sources. This describes one
current Ka-Band radio source and how an RO system
could be implemented, as well as some projected data
quantity and data utility for ingesting into the forecast
models.
Acknowledgements
This symposium is sponsored by Center for Environmental

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A distinct stronger warming in the tropical tropopause layer during 2001-2010 using GPS
radio occultation: Association with minor volcanic eruptions
Sanjay Kumar Mehta1, Masatomo Fujiwara2, Toshitaka Tsuda1, Jean-Paul Vernier3
1
Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Japan; 2Faculty ofEnvironmental Earth Science, Hokkaido University, Japan; 3Science Systems and Applications, Inc.,
Hampton, VA 23666, United States.
Abstract
The trends and various interannual variability components in the tropical tropopause layer (TTL) over thetropics (15oS-15o N) were examined by employing upper air data from GPS radio occultation (RO), radiosondes(IGRA, RICH, and HadAT2), and ERA-Interim during the period 2001-2010. The detection capability of the GPS
RO, though with limited data coverage, has been shown in previous studies. A detailed analysis of the warming
observed in the TTL from 2001 to 2010 using both standard linear and multiple regressions is carried out. The
temperature trends estimated using standard linear regression analysis (with only constant and linear trend terms)
reveals a strong warming of about 0.5-1.5 K/decade in the TTL in each dataset during 2001-2010. This strong
warming in the TTL is not explained by the global warming. The contribution from various interannual variability
components such as quasi-biennial oscillation (QBO), El Niño southern oscillation (ENSO), and stratosphericaerosol optical depth (AOD) is separated using multiple regression analysis techniques. We performed two typesof multiple regression analysis that do not consider and that consider seasonal modulation of the interannualcomponents. The distinct warming in the TTL is found to be partly associated with the minor volcanic eruptions
during the first decade of the 21st century. Positive and significant AOD responses to the temperatures of about
0.1-0.2 K are observed in the TTL region, explaining about 5% to 15% of the total variance during 2001-2010.
Keywords : Tropical tropopause layer, temperature trend, minor volcanic eruptions
1. Introduction
GPS radio occultation (RO) measurements are
independent and calibration free, and they provide
high-quality observations to monitor the TTL with global
coverage and essentially all-weather capability andconsistency [Kussinski et al., 1997]. The climate utility of
GPS RO has been demonstrated in several earlier studies andmore recently Steiner et al. [2009] observed that even short
GPS RO records show tropospheric warming andstratospheric cooling, and pointed out the capability of GPS
RO to become the future climate benchmark, reported
warming in the tropical tropopause region for the period
February 1997-2008. Recently, an increased amount ofstratospheric aerosol due to minor volcanic eruptions wasobserved about 17-21 km during the first decade of the 21st
century [see Vernier et al., 2010], which might have hadsome influence on this stronger warming from 2001 to 2010.
The central objective is to discuss the impact of minor
volcanic eruptions on the distinct stronger warming observedin the TTL during the period 2001-2010.

was applied to the smoothed temperature anomalies ( ) of
GPS RO, adjusted and unadjusted radiosondes and
ERA-Interim at each altitude and pressure level, which canbe expressed as [Randel and Cobb, 1994]:

where t is the month index (t=1,2,…,112, for September
2001 to December 2010),
is the constant term,isthe linear trend, and,, andare regression
coefficients for QBO, ENSO, and AOD, respectively. The
term
denotes the residual time series, representing theregression error, whereas
andare the time lags ofthe temperatures at given altitude or pressure levels with the
QBO and ENSO, respectively. In this study, we do two typesof regression analysis by using equation (1); for the first typeof regression, the coefficients ,
,
,
, and
are treated as the constants (method-1 hereafter), and for thesecond type, these coefficients () are allowed for theseasonal modulation (time-dependent) given by aconstant () plus annual (12-month), semi-annual(6-month), and quarterly (4-month) expressed in the form

2. Methods
To isolate and extract each specific signal quantitatively so
as to estimate trends, a simple multiple regression analysis,where(method-2 hereafter).

21

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SOMIRES2013-231th RISH

using method-1.
We further removed the seasonal dependence of the QBO
and ENSO, if any, while using regression method-2 andestimated the temperature trends in each dataset over theperiod 2001-2010, as shown in Figure 1c. Figure 1c shows
overall tropospheric warming and stratospheric cooling. A
comparison of Figures 1c and 1b reveals that there is nochange in the trend patterns except between 16 and 19 km.
Thus, it appears that removing the seasonal dependence of
the QBO and ENSO is important not only for the regression
fits but also for the precise estimation of the temperature
trends; otherwise the results will be contaminated with alarge residual associated with the seasonality in the QBO andENSO. We then applied method-2 while taking into accountthe AOD along with the QBO and ENSO, and estimated thetemperature trends as shown in Figure 1d. Figure 1d also
shows overall warming in the troposphere up to about 15 to
16 km and cooling in the stratosphere. The temperature trend
pattern between 16 and 19 km, as evident from Figures 1a to
1c, changed significantly on removing the AOD.

3. Results and Discussion
We applied the standard linear regression method,at pressure
regression method-1, and method-2 to thelevels (altitudes) up to 30 hPa (25 km), and the annual mean
temperature trends along with standard errors at 2-sigma
level (95% confidence interval) were estimated in eachdataset over September 2001-December 2010, as shown in
Figure 1.

4. Summary
The distinct stronger warming trend (0.5-0.8 K/decade) in
the TTL between 16 and 19 km reported earlier and in thecurrent study using method-1 is observed to be partly due toseasonality in the QBO and ENSO and partly due to theminor volcanic eruptions during the first decade of the 21st
century. Removing them using method-2 results in an
insignificant temperature trend due to anthropogenic climatechange in the TTL between 16 and 19 km during 2001-2010.
A positive and significant AOD temperature response ofabout 0.1-0.2 K is observed in the TTL between 16 and 19
km during 2001-2010, which explains about 5% to 15% of
the total variability.

Fig. 1 Altitude profile of temperature trends
The temperature trends from unadjusted radiosonde(IGRA5 and IGRA25) and GPS RO data while those fromadjusted radiosonde (RICH and HadAT2) and ERA-Interim
data are plotted separately, to avoid clumsiness due to theirdifferent vertical resolutions. Estimation of the trend using
standard linear regression (Figure 1a), in fact, allows
contribution from the potential interannual variability
components in the troposphere and stratosphere besides thecontributions from the anthropogenic variability. Eachdataset, except for GPS RO, shows an insignificant warming
trend in the troposphere up to 15 km and insignificant
cooling above 20 km. There is a distinct and significantly
strong warming layer in the TTL between 16 and 19 km(100-70 hPa), with a maxima at about 18 km in each dataset
during the period 2001-2010. A comparison of Figures 1aand 1b reveals that the error bar becomes smaller due tobetter regression fits using method-1 when compared withstandard linear regression. Between 16 and 19 km, thechange in the temperature trends estimated with (Figure 1b)
and without (Figure 1a) considering the QBO and ENSO are
within statistical reliability. The temperature trend between
16 and 19 km from GPS RO and unadjusted data is about
0.84±0.39 K/decade and that from adjusted data is(0.52±0.37) K/decade after removal of the QBO and ENSO

Acknowledgements
This work is supported by the Japan Society for the
Promotion of Science (JSPS) Foundation (ID No. P12025).
References
Kursinski et al (1997), J. Geophys. Res., 102, 23,429–23,465,
doi:10.1029/97JD01569.
Randel and Cobb (1994), J. Geophys. Res., 99(D3),5433–5447, doi:10.1029/93JD03454.
Steiner, et al (2009), Geophys. Res. Lett., 36, L18702,
doi:10.1029/2009GL039777.
Vernier, J.‐P., et al. (2011), Geophys. Res. Lett., 38, L12807,
doi:10.1029/2011GL047563.

22

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SOMIRES2013-231th RISH

Development of Compact Plasma Instrument（TeNeP） for Nano and microsatellite
K. -I. Oyama, C. Z. Cheng, Yu-Wei, Hsue
Plasma and Space Science Center, National Cheng Kung University, Taiwan
oyama@pssc.ncku.edu.tw
Abstract
The satellites for the educational purpose are being manufactured in many Universities in the world. Their weight
ranges from several kg to 20 kg. However most of the satellite seems to be engineering oriented. For the scientists,these Nano/micro satellites constellation might provide excellent chances to conduct new sciences and to increase
the research opportunities. In order for the science instruments to be accommodated in the Nano/microsatellite,
the following factors need to be fulfilled; 1.The small dimension/low power consumption of the instrument, anddata bit rate should be very small. 2. The sensor should be easily deployed or fixed without complex mechanism
and, 3.The weight of the sensor should be right so that its deployment should not disturb the attitude of thesatellite. These requirements are fundamentally important for the instrument to be accommodated in tinysatellites. It goes without saying that even small instrument should have a good performance in addition toprovide accurate, and reliable information. Here we developed one plasma instrument to measure both electron
temperature and plasma density simultaneously. Frequency sweep circuit is added to the conventional electron
temperature probe [1]. The electron temperature probe which was developed more than about 30 years ago was
accommodated in 5 earth orbiting satellites as well as Mars orbitor, and about 50 sounding rockets in Japan
including the sounding rocket in Antarctica. The probe was used for the sounding rocket experiment in India,
Brazil[2], Canada, U.S.A, and West Germany. The probe was also accommodated in Korean, Brazil, and Russian
satellites.
The circular electrode (100 mm in diameter, and 1.6 mm in thickness) should be ram direction of the satellite,
and it should be about 30 mm away from the satellite wall, to avoid the measurement in the satellite wake and in
the sheath. The electronics consists of frequency sweep circuit (200 KHz-10 MHz), amplitude modulation circuitand conventional electron temperature probe. The total weight, and power is about 200 g and 500 mW
respectively. The bit rate of 2kbits/sec allows us to calculate electron density from upper hybrid resonance. This
amount of bit rate also makes it possible to calculate electron density and temperature from the output signal of
the instrument in low frequency (200 KHz), which allows us to compare electron densities both from upper hybrid
resonance and from the output signal of the electron temperature probe. The measurement duration is about 1 sec.
The instrument can be accommodated in 10 kg satellite, that is, the instrument can be accommodated to allsatellite of constellation. One of the research subjects by using satellite constellation is to study the precursor
features associated with large earthquakes [3,4,5].
Keyword: Instrument, Ionosphere, Nano/Micro satellite,
References
1) Oyama, K.-I., Verification of IRI plasma temperature at great altitude by satellite data (INVITED), presented
in COSPAR in Washington, Adv. Space Res., 14, (12)105-(12)113, 1994.
2) MURALIKRISHNA, P., M.A. ABDU, J.H.A. SOBRAL, KOH-ICHIRO OYAMA "Plasma Diagnostic
Experiments on Board of the First Brazilian Scientific Micro satellite - SACI-1", Geofísica Internacional,
39,127-133, 2000.
3) Oyama, K.-I. ,Y.Kakinami, J.Y.Liu, and M.Kamogawa, and T.Kodama, Reduction of electron temperature in
low latitude ionosphere at 600km before and after large earthquakes, J.Geophys.Res.,
doi:10.1029/2008JA013367,2008.
4) Oyama, K. -I., Y.Kakinami, ,J.Y.Liu, T.Kodama, and C.Y.Chen, Micro/mini satellites for earthquake studies toward international collaboration, Advances in Geoscience, 21, 251- 256, 2010.
5) Oyama, K.-I., Y. Kakinami, J. Y. Liu, M. A. Abdu, and C. Z. Cheng, Anomalous Ion Density Latitudinal
Distribution as a precursor of large earthquake, J.Geophys. Res., 116, A04319, doi:10.1029/2010JA015948,
20116) Oyama, K.-I., T. Abe, K. Schlegel, A. Nagy, J. Kim, and K. Marubashi, Electron temperature measurement in
Martian ionosphere, Earth and Planetary Science, 51, 1309-1317, 1999

23

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SOMIRES2013-231th RISHELMOS Constellation: Lithosphere, Atmosphere and Ionosphere Monitoringby Small and Microsatellites
Tetsuya Kodama
Earth Observation Research Center, JAXA, kodama.tetsuya@jaxa.jp
Abstract
GPS radio occultation is a simple and precise observation tool of the atmosphere and the ionosphere, particularly
for improvements of the forecasting accuracy on the numerical weather prediction [ex. Formosat-3/COSMIC].
Recently, Global Navigation Satellite Systems(GNSS) have been established not only GPS Navstar but also
GLONASS and Beidou, Galileo, QZSS and IRNSS are under development. This means that atmospheric andionospheric data obtained by GNSS radio occultation will definitely increase in near future.
As conventional earth observation satellites are on sun-synchronous orbit, it is impossible to obtain diurnal
variations of the atmosphere and the ionosphere, therefore small and microsatellite constellation is the solution
within the realistic resources. Especially, the discrimination between seismo-origin and non seismo-origin
perturbations of the atmosphere and ionosphere, it is necessary that comprehensive understand of atmosphericionospheric phenomena by satellite constellation.
Keywords : GPS occultation, lithosphere-atmosphere- ionosphere coupling, small satellite, microsatellite
follows.
・GPS occultation receiver
・Plasma probes (electron density/temperature)
・VLF receiver・Vector electric field probes
・2D CCD camera
・Energetic charged particle analyzer
・Topside sounder・Ion/neutral mass analyzer
・Neutral wind meter
・Plasma drift meter
・Atomic oxygen detector
・Magnetometer・Technical Data Acquisition Equipment (TEDA)
Particularly, we expect promising results ofseismo-electromagnetic research based on the reliable timeand space ionospheric model by satellite constellation.

1. ELMOS Constellation
We have already proposed the ELMOS small satellite
constellation since 2010. All the satellite equip 3 common
instruments; GPS occultation receiver, electron density andtemperature probes which are internationally acclaimed. Its
altitude is around 500～600km and the inclination is 40～50
deg.

Fig. 1 ELMOS Constellation

2. Mission Objectives
Mission objectives of the ELMOS constellation are as
follows;
1. Practical Utilization: improvement of the weather forecast
accuracy by GPS occultation measurement
2. Scientific Research from the Ionosphere to the
Lithosphere: contributions to the International Reference
Ionosphere, ionosphere-atmosphere coupling, mesosphere,
thermosphere, terrestrial gamma ray flash, transient luminous
events, seismo-electromagnetics and oceanography etc.
3. Engineering Applications: space environment, space
weather and ionosphere scintillation monitoring which isharmful for navigation communications
Mission instruments of the ELMOS main satellite as

Fig. 2 Ionospheric Dynamics (UCLA)

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At the Chiba university, two microsatellites named
GAIA-I and GAIA-II are under development scheduled tolaunch in 2017 by Josaphat laboratory. The GAIA-I is
installed GPS occultation receiver, electron density andtemperature probes for seismo-ionospheric observation.
As an overseas activity, the Small Satellite Payload Task
Group has been authorized under the Asia Oceania
Geoscience Society in 2013. The task group is expected toprovide an opportunity to discuss all aspects of the mission,from scientific goals that attract common interest such as
earthquake precursors to candidate instruments as well assatellite systems.
Thus, it would be possible without increasing the program
cost, thereby both an increase in the number of constellation
satellites simultaneously with miniaturization of the satelliteby the international cooperation.
In order to provide launch opportunities continuously fordomestic and overseas microsatellite, it is strategically correctthat JAXA have to reduce their own satellite program cost bysmall satellite for continuous launch of H-IIA or Epsilon.

3. Success Criteria
Success criteria of the ELMOS constellation is as follows.
Minimum

NominalPractical

Establishment of

Improvement

UtilizationGPS

weather

RO

Extra
of

forecast

Establishment
GPS

of

Ocean

technology

accuracy

ScientificData acquisition

DevelopmentofEstablishing Proof

Research

byReliableandofonboardreflection

Pre-seismicscientificaccurate

Ionosphericinstruments

Ionospheric modelPrecursors

Engineering

Data acquisition

Space

env.

Research

Applications

by TEDA

monitoringfor

anomaly events by

JAXA

Satellite

long-term

Design Standards

operationof

4. Option Plan and Future Initiative
Since 2006, JAXA has been studying development of theSuper Low Altitude Test Satellite (SLATS). If the SLATS
become practical use, it is possible to observe various
physical values directly in the F-layer of the ionosphere withELMOS constellation.

References
1) Kodama and Oyama, The ELMOS Small Satellite
Constellation, The 28th ISTS, 2011.
2) Kodama
et al., The ELMOS Small Satellite
Constellation, The 43rd Annual Meeting of the Japan
Society for Aeronautical and Space Sciences, 2012.
3) Uyeda et al., Proposal for Earthquake Prediction
Program I: Short-term Prediction, Japan Geoscience
Union Meeting, 2012.
4) Uyeda et al., Proposal for Earthquake Prediction
Program II: Satellite Observation, ibid5) Kodama, A Review of Seismo-Electromagnetic Satellite
Missions - Recent Results and Prospects -, EMSEV2012 in Japan, 2012.
6) Research and Development of an Ion Engine for a
Super-Low-Altitude Satellite, Sora to Sora, No.42, 20117) Japan Advances
University-led
Microsatellite
Constellation, Spacenews, Dec. 3, 20108) Microsatellite Powerful Earthquake Prediction 4 Days
Before Happen, KOMPAS, June 26, 20129) Center for Environmental Remote Sensing Newsletter,
No. 90, 201310) http://www.geocities.jp/s2ptg/
11) Kodama et al., Temporal and Spatial Observation of
Atmosphere-Ionosphere by Small Satellite Constellation,
The 44th Annual Meeting of the Japan Society for
Aeronautical and Space Sciences, 2013

Fig. 3 SLATS (JAXA)

Japanese university-based microsatellite community dates
back more than a decade, with most activities coordinatedunder the UNISEC that are steadily building increasingly
functional satellites faster and cheaper nowadays.

Fig. 4 Microsatellite GAIA-I and-II (Kompass)

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SOMIRES2013-231th RISH

GPS Total Electron Content (TEC) for Ionospheric Observation
Katsumi Hattori1, Shinji Hirooka1, Chie Yoshino1, Yuichi Otsuka2
1
Graduate School of Science, Chiba University, Japan
2
Solar-Terrestrail Environmental Laboratory,Nagoya University, Japan
E-mail hattori@earth.s.chiba-u.ac.jp
Abstract
Total electron content (TEC) investigation is one of the powerful tools in ionsopheric study. Several case studies and statisticalstudies on storms, tsunami, earthquakes, and so on have been performed. To understand the mechanism, monitoring of
three-dimensional distributions of ionospheric electron density is effective. In order to investigate the three-dimensional
structure of ionospheric electron density, the neural network based tomographic approach is adapted to GEONET and
ionosonde data. However, it is an ill‐posed problem in the context of sparse data, and accurate electron density reconstruction
is difficult. The Residual Minimization Training Neural Network (RMTNN) tomographic approach, a multilayer neuralnetwork trained by minimizing an objective function, allows reconstruction of sparse data. In this study, we validate thereconstruction performance of RMTNN using numerical simulations based on both sufficiently sampled and sparse data. First,
we use a simple plasma‐bubble model representing the disturbed ionosphere and evaluate the reconstruction performancebased on 40 GPS receivers in Japan. We subsequently apply our approach to a sparse data set obtained from 24 receivers inIndonesia. The reconstructed images from the disturbed and sparse data are consistent with the model data, except below 200
km altitude. To improve this performance and limit any discrepancies, we used information on the electron density in the lower
ionosphere. The results suggest the restricted RMTNN‐tomography‐assisted approach is very promising for investigationsof ionospheric electron density distributions, including studies of irregular structures in different regions. In particular, RMTNN
constrained by low‐Earth‐orbit satellite data is effective in improving the reconstruction accuracy.
Many anomalous electromagnetic phenomena possibly associated with large earthquakes have been reported. TEC(Total Electron Contents) anomaly is one of the most promising phenomena preceding large earthquakes. In this study, TEC
anomalies before large earthquakes have been investigated. TEC values are computed by using the GEONET and GIM(Global Ionosphere Maps). 15 days backward running average (TECmean(t)) and its standard deviation  (t) at a specific time
are taken for the normalization. The normalized TEC, GPS-TEC∗(t) is defined as TEC∗ (t) = (TEC(t)-TECmean(t))/(t). We
investigate TEC anomalous changes in times and space from May1998 to May 2010 in case and statistical studies. Results
show that positive anomalies significantly appear 1-5 days before M>=6.0 earthquakes in Japan area. In addition, weinvestigate the 2011 off the Pacific coast of Tohoku Earthquake. GIM-TEC∗ anomalies exceeding +2 appear 3-4 days before
the earthquake. The duration is more than 20 hours. This result is consistent with the previous statistical results of positive
anomalies for M>=6.0 earthquakes in Japan area.
To understand the mechanism, monitoring of 3D distributions of ionospheric electron density is considered to beeffective. In this study, to investigate the three-dimensional structure of ionospheric electron density prior to large earthquake,the neural network based tomographic approach is adapted to GEONET and ionosonde data for the 2011 Off the Pacific Coastof Tohoku Earthquake (Mw9.0). As mentioned above, significant enhancements of TEC are found 1, 3-4 days prior to theearthquake. Especially, TEC increase of 3 days prior to the earthquake was remarkable. As a result of tomographic analysis, thereconstructed distribution of electron density was enhanced in sub-ionosphere to over F-region in comparison with 15 days
backward median distribution. Moreover the enhanced area seems to be developed to upper ionosphere from sub-ionospherewith time. The rise velocity along magnetic field line was approximately 70 m/s. The tomographic results suggest the existenceof some energy influx from the surface associated with seismic activity. Then, in order to understand the relationship ofdetected phenomenon and earthquake, we performed the tomographic analysis for other earthquakes occurred in Japan. The
details will be shown in the presentation.

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Ionospheric Observations of FORMOSAT-3 and follow-on FORMOSAT-7
Tiger J. Y. Liu1,2, G. S. Chang1, S. J. Yu1, T. Y. Liu1
1
National Space Organization (NSPO), TAIWAN
2
Institute of Space Science, National Central University, TAIWAN

Abstract
The FORMOSAT-3/COSMIC (F3/C) constellation lunched on 15 April 2007, which consists of six
micro-satellites in the low-earth orbit, is capable of monitoring the ionosphere by using the powerful technique ofradio occultation. With more than 1500 observations per day, it provides an excellent opportunity to monitor
three-dimensional structures and dynamics in the electron density and scintillation of the ionosphere. Many
prominent features of equatorial ionization anomaly, plasma cave, middle latitude trough, the Weddell Sea
anomaly, sudden stratospheric warming, irregularity, etc. in the ionosphere are observed. Finally, simulation
results of ionospheric observations by the F3/C follow-on, FORMOSAT-7, are presented.

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SOMIRES2013-231th RISH

Development of Space borne X Band SAR for 100kg Satellite
Hirobumi Saito 1, Atsushi Tomiki 1, Prilando Rizki Akbar1,
Takashi Ohtani2, Kunitoshi Nishijo2, Jiro Hirokawa3, and Makoto Ando3
1
Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science,2
Aerospace Research & Development Directorate, JAXA, 3Tokyo Institute of Technology
E-mail saito.hirobumi@jaxa.jp
Abstract
We have started development of small synthetic aperture radar (SAR) compatible to 100kg class small satellites
with about 3m ground resolution and multi-polarization, aiming for constellation SAR observations. This
technology enables us to realize high frequency SAR observations with only several hours observation interval.
This paper describes key technologies of this development such as deployable slot array antennas, waveguidefeeder with a small gap at a deployment point, and GaN HEMT X band amplifier. Also we show an integration
design result of this SAR system to 100kg class bus system.
Keywords : X band SAR, 100kg Small Satellite, slot array antenna, SAR constellation
observe the earth in a limited time for example less than10%.
Therefore, an advantage of a piggy-back satellite with a
SAR is to increase in observation frequency with relatively
low resolution observations. Piggy-back launch is a costsaving way to inject in different orbits many piggy-backsatellites with SARs. A system of 12 piggy-back satellites
with SARs affords a short revisit time of less than 10 hours.
Probably the total cost is less that one of single large SAR
satellite.
Candidates of applications that require short revisit time
are disaster managements and maritime security to observe
objects exposed at earth surface without covering vegetation.
It implies that X-band observation is adequate for a small
SAR compatible with a piggy back satellite.

1. Introduction
Synthetic Aperture Radar (SAR) is a well known remotesensing technique with reliable capabilities that offer advantages
over an optical sensor. However, SAR sensors require relatively
large antennas with several meters and high RF power ofhundreds watts or more. Up to now, only large or medium size
satellites with hundreds kilo-grams or more can afford SAR
sensors. These large or medium satellites cost hundreds
million US dollars including launching cost.
In this paper, we propose a synthetic aperture radar sensor
compatible with 100kg class piggy-back satellites. A 100kg
satellite may cost roughly ten million US dollars. Furthermore
it can be injected into an orbit as a piggy-back, resulting in total
mission cost of less than twenty million US dollars..
In the next section, we discuss on the system goal andspecifications of SAR that is suitable for a small satellite. Finally,
the conclusion and future research will be summarized in
section 3.

2.2 System Description of Small SAR
We have performed a preliminary parameter design of apiggy-back satellite with a SAR [1]. It is concluded that X
band is a good choice for a compact SAR antenna. Also
X-band is adequate to observe objects exposed on the
ground, which is the main target of a small SAR with a shortrevisit time. A transmitting RF power is 573W.We aredeveloping a high efficiency GaN RF power amplifier, inwhich we improve to increase operational duty ratio up to
20-30%. The ground resolution is 6.1m in a case ofnoise-equivalent sigma zero NE= -20dB and the duty
ratio 20%.
A key technology of the small SAR compatible with apiggy-back satellite is a deployable plane antenna array.
Maximum envelop size of a piggy back satellite is 70 x70 x
70cm3 and size of one antenna panel is selected to be 70

2. Small SAR Compatible with Piggy-Back Satellite
2.1 System Goal of Small SAR
Piggy-back launch is inexpensive method to inject a small
satellite to an orbit. We have started development of a small
satellite with a SAR sensor, which is compatible topiggy-back launch. Japanese H2A vehicle afford a
maximum piggy-back satellite with 70x70x70 cm3 volume
and around 100kg mass.
Recently a medium or large SAR sensor has a highresolution of 1 meter or less. However, in most cases, a SAR
sensor can operate for 5-10minutes in an orbit period ofaround 100 minutes because of power constraint. At
present, a few number of medium or large SAR satellites can

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cmx70cm. Waveguides have the lowest transmission in thisfrequency region. Single layer slotted waveguide antennas
are a good candidate for this application [2]. We aredeveloping a RF feeder system based on waveguide, whichis compatible with deployment and has low loss. The
satellite deploys two wings each of which consist of threeantenna panels. Antenna arrays are also on the satellite bodyand the total size of the antenna is 0.7m x 4.6m. Figure 1
shows a preliminary outlook of the satellite.
A SAR sensor radiates high RF power in a shortobservation time. Time profiles of power and heat of thissatellite have a very high peak-average ratio. This satellite
has to manage the issue of a high peak-average ratio under
severe constraint of mass and volume. In addition toconventional satellite technologies, several advanced
technologies would be applied to solve these issues. A
solution of the power management is to apply olivine-type
lithium-ion batteries compatible for high discharge rate.

Table 1 Main Parameters of Small SAR

Conclusions
This paper describes the goal and system description of apiggy-back satellite with a small SAR. The systemanalysis shows that a ground resolution of several meters is
possible with X-band. Possible applications are to form a
constellation of several piggy-back SAR satellites fordisaster managements and maritime security, which require
short revisit time.
A preliminary satellite design is in progress. The total
mass of satellite is 100kg mass and the satellite iszero-momentum 3-axis stabilized. The details will bereported in the conference.
References[1] P.R. Akbar, JT Sri Sumantyo, and H. Saito, “Design ofsynthetic aperture radar onboard small satellite,”International Conference on Space, Aeronautical andNavigational Electronics 2012, SANE2012-80, Incheon,
Korea, 2012.
[2] K. Sakakibara, J. Hirokawa, M. Ando, and N. Goto, “Ahigh-gain and high-efficiency single layer slotted waveguidearray for use in 22GHz band,” IEE Electronics Letters,
vol.32, no4, pp.283-284, 1996.

Parameter

Value

Frequency (GHz)
Altitude (km)
Off Nadir ()Pulse Bandwidth (MHz)NE (dB)
Resolution (m) (Number of look = 4)
Swath Width (km)Antenna size (m)Peak Power (W)Average Power (W)System Noise Temperature (K)Noise Figure (dB)
System Loss (dB)
Antenna Efficiency
Transmitter Duty Cycle
SAR Battery Capacity (Wh)SAR Battery Mass (kg)Operational Battery Capacity (Wh)Operational Battery Mass (kg)Power Control & Converter Unit Mass(kg)Operational
SAR Observation
Solar Paddle Area (m2)

9.65
510
21
40
-25
9.8
23
4.9 x 0.7
573
230
589
4.8
4
0.6
0.4
127
1.26
26.39
0.26
5
9.57
>0.67

Fig.1 Outlook of Piggy-back Satellite with Small
Synthetic Aperture Radar. Mass is 100kg andbody size is 0.7x0.7x0.4m3. Two wings of SAR
antennas are deployed and each antenna panel is0.7x0.7m2. Back side of SAR antenna is partiallysolar cell.

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SOMIRES2013-231th RISH

SAR Antenna Development in the UK
Steven Gao1, Yohandri2,3 and Josaphat Sumantyo2
1
University of Kent, Canterbury, UK
Email: s.gao@kent.ac.uk
2
Physic Department, State University of Padang, Indonesia
Email: yohandri@fmipa.unp.ac.id
3
Centre for Environmental Remote Sensing, Chiba University, Japan
Email: jtetukoss@faculty.chiba-u.jp
Abstract
Antenna sub-system is one of the most critical and expensive sub-systems for Synthetic Aperture Radar (SAR)
onboard aircraft or satellites. This paper provides a brief overview of SAR antenna development in the UK. Some
results will be shown. The conclusion and future development of SAR antenna and systems in the UK are given in
the end.
Key words: SAR, phased array, space antenna
EADS Astrium UK Ltd, Surrey Satellite Technology
Ltd (SSTL), Selex, BAE Systems, Qinetiq, as wellas academic institutes such as the University of Kent,
University College London, University of Sheffield,
University of Surrey, etc. Some examples of recent
space-borne SAR systems include ERS-1 (C band),ASAR on ENViSAT (C band), NovaSAR-S (Sband), Sentinel-1 (C band), AstroSAR-Lite (X band),etc. A variety of antenna technologies have beendeveloped for SAR systems, including printed
microstrip patch arrays, slotted waveguides,
deployable antennas, horn antennas, annular slot
arrays, active phased arrays, etc [1]. As an example,
the antenna sub-systems for NovaSAR-S are
explained below.
NovaSAR-S is a low-cost radar imaging satellite,
recently developed by SSTL and Astrium UK Ltd[2-3]. One key drive of NovaSAR-S development is
to significantly reduce the cost of space-borne SAR
systems while improving the performance ofimaging. This is made possible by adopting themodern small-satellite platform technology, newantenna technology and new RF sub-systemtechnologies. NovaSAR-S operates in S-band (3.13.3 GHz) and has a design life of 7 years. The total
mass of the satellite including SAR system is below
400 kg. It can operate in single (e.g., HH or VV) or
multiple polarizations (HH, VV, HV and/or VH).
The modes of operations are highly flexible,
including ScanSAR (narrow), Stripmap, ScanSAR(wide swath width), and a maritime surveillance
mode. In single-polar operations (e.g., HH or VV),
spatial resolutions in the range 6-30m are achieved
with corresponding swath widths ranging from 15-

1. Introduction
Due to the capabilities of day-and-night
operation and penetration through clouds and rain,
SAR has become an important tool for earth
observation
andenvironmental
monitoring
worldwide. Space-borne SAR systems are usually
very expensive and take many years from thedevelopment to launch. One of the recent trends is todevelop low-cost SAR systems onboard small
satellites. In Europe, one of the recent examples is
the COSMO-SkyMed (Constellation Of Small
Satellites for Mediterranean basin Observation) is afour-satellite constellation funded by ASI (Agenzia
Spaziale Italy) and the Italian Ministry of Defense.
The four satellites, from Thales Alenia Space, Italy,
were launched during 2007 and 2010, and eachsatellite is equipped with a SAR operating at X bandwith multiple operation modes (Spotlight, Stripmap
and ScanSAR) and multi-polarization capabilities.
The multi-mode and multi-polarization capability of
SAR is achieved by using an active phased array for
the SAR antenna onboard. The COSMO-SkyMed
allows both the wide-area mapping (at low
resolution, ScanSAR mode, X band) and the highresolution imaging (in Spotlight SAR mode, X band)of the Mediterranean latitudes with repetition time ofa few hours. A brief review of SAR antennadevelopment will be given in the following.

2. Brief Review of SAR Antenna in the UK
and Some Results of Low-Cost SAR
In the UK, many SAR systems have beendeveloped during recent decades. These SAR
systems mainly operate at S band, C band, X band,
both S/X band, etc, for air-borne or space-borne
applications. Key players in SAR systems andrelated technologies include companies such as

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150 km. The maritime surveillance mode is uniqueand it has a surveillance swath of 750 km width fordetecting the ships or other targets in the ocean. The
optimum orbital altitude for NovaSAR-S is 580km.
The highly flexible modes of NovaSAR-S are
enabled by using an active phased array antenna.
Figure 1 show the antenna array which is a
microstrip-patch active phased array consisting of 18
sub-arrays. The total size of the antenna array is 3
m×1 m. The antenna can achieve multi-polarizations(VV, HH, VH, HV). To achieve electronic beamsteering, the antenna is integrated with microwave
phase shifters which are controlled by DC voltages.
To reduce the size and mass (and cost) of SAR
antenna system, it is integrated with GaN power
amplifiers. The use of GaN technology is important
here for significantly reducing the size and mass ofactive phased array, due to the high power density
capability of GaN devices in comparison toconventional GaAs technologies.

modes in the sub-array, leading to high polarization
purity and high isolation between transmit andreceive [1,4].

Figure 2 Sub-array of SAR antenna for
NovaSAR-S [2,3]3. Conclusion and Future
The above provides a brief overview of SAR
antenna in the UK. One of important steps next is todevelop digital beamforming (DBF) multi-static
SAR. The University of Kent, teamed with DLR(Germany) and other European partners, is working
on DBF multi-static SAR for a constellation ofseveral micro-satellites in low earth orbits. Such a
SAR system requires DBF array antennas and novel
algorithms for antenna adaptive beamforming.

Acknowledgement
The author thanks the support from Japan Society
for Promotion Science (JSPS) fellowship
programme, Japan.

References
1) W. Imbriale, S. Gao and L. Boccia, Space
Antenna Handbook, Wiley, UK, May 2012
2) Web: http://www.sstl.co.uk/NovaSAR-1
3) P. Davies, et al., NovaSAR – Bringing Radar
Capability to the Disaster Monitoring
Constellation, Proceedings of The 4S
Symposium 2012, Slovenia, June 2012, pp.1-124) R. Di Bari, T. Brown, S. Gao, C. Underwood, etal., Dual-Polarized Printed S-Band Radar Array
Antenna for Spacecraft Applications, IEEE
Antennas and Wireless Propagation Letters, Vol.
10, 2011, pp. 987-990

Figure 1 SAR antenna for NovaSAR-S [2,3]One challenge of SAR antenna is to improve thepolarization purity and increase the isolation
between transmit and receive chains. This isachieved by using the “anti-phase technique”. Figure
2 shows the configuration of one sub-array. As
shown in Figure 2, the radiating elements (squaremicrostrip patch) in the 1st row and the 2nd row are
fed at opposite positions. This will excite electric
currents following in opposite directions on theelements in the 1st and 2nd row. To compensate this,these two rows will be fed with 180o phasedifference between them. Such an “anti-phasetechnique” enables the cancellation of high-order

31

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Micro SAR Satellite Development in Korea and a Plan ofSpace Observation Network in Southeast Asia
Tu-Hwan Kim†, Dal-guen Lee†, Jae-Hyun Kim‡, Hee-In Yang‡†Department of Space Survey Information Technology, Ajou University
San 5, Woncheon-dong, Yeongtong-gu, Suwon, 443-749 Korea‡Department of Electronics Engineering, Ajou University
San 5, Woncheon-dong, Yeongtong-gu, Suwon, 443-749 Korea

E-mail : †{thkim@ajou.ac.kr, dalguen84@gmail.com}, ‡{ jhkim,@ajou.ac.kr, kfcddong@gmail.com

Abstract Recently, Ajou University, Korea with Institute of Space and Astronautical Science (ISAS) and Chiba
University, Japan has done the micro satellite project. Research topics are high speed downlink communicationand synthetic aperture radar (SAR) system. Based on these technologies, Ajou University has a plan to offer small
satellite for industries and other countries by cooperating with other companies. Especially micro satellites andground stations for the micro satellite is offer for Southeast Asian countries that have natural disaster. The final
goal is to construct earth observation network and the very long base-line interferometer (VLBI) system bycooperating with Korea and Japan.
Keywords : Micro satellite, SAR, Korea-Japan space cooperation, Space observation network, VLBI

Figure 1. Korea National Space Program Roadmap

government has a plan to launch a next generation microsatellite per 3~4 years. The core technologies for the microsatellite are an ultra-light and low-power X-band RF
transmitter-receiver, wireless inner satellite networks for
substituting instrumentation wired networks and etc. These
technologies have been not studied in Korea before, Ajou
university collaborate with Space science lab in JAXA,
Japan which develops the high speed downlink transmission
technology in satellite networks. And also Ajou University
have made a MOU with professor Josaphat in National
Chiba University, Japan who are excellent for developmentof the micro SAR satellite. The mirco SAR satellite is mostpopular as the utility of the micro satellite.
If the micro SAR satellite is developed by National Space
Program, Ajou University will develop the standard satellite

1. Korea-Japan joint development of next generation
micro SAR satellites
The micro satellite can be developed at low cost in a shortperiod of time while the large satellite development will takea long period of time to research and need a huge amount ofinvestment. Therefore, the micro satellite development has anadvantage in the development of space technology. As
shown in Figure 1, this micro satellite development isincluded as part of the "Korea
National Space Development Program Roadmap" bydetailed action plan. The proven technology in the microsatellite can be adapted to the large multi-purpose satellite in
the future. The multi-purpose satellite can be made in Korea
by the using the micro satellite technologies. And Korea

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for micro satellite with corporations and supply it to domestic
and foreign countries. Then it will help to accelerate thespace industry. Especially, it contributes to the advancementof science and economy of countries in Southeast Asia whichhave rich resources and many natural disasters.

Figure 2. A plan of observation network in Southeast Asia

For determining the point, the country should install thegeodetic VLBI observatory station and then do theinternational VLBI observation. The measured point
becomes an origin point of the national geodetic system, andthe new coordinates system of the whole country are
determined based on it. Finally, the new national geodetic
system is established based on the world geodetic system.
For the geodetic VLBI observation, if the diameter of anantenna at one side is more than 20m, then 3m is acceptable
as a diameter of the other side antenna. As shown in Figure 2.
if the space VLBI station (in Sejong-si, Korea) which has the
22m-diameter antenna play a role as the central station, thenthe geodetic VLBI observation can be possible by using thesmall ground station with the 3m-diameter antenna inSoutheast Asia. For that, only requirement is that the
replacement of the antenna receiver for the satellite
communication with for the geodetic VLBI receiver.
When the geodetic VLBI observation is possible, eachcountry can not only determine the origin point of the newnational geodetic system, but also measure the variation ofplate movements in Southeast Asia region. Therefore, they
can minimize damages from the natural disaster such as
earthquake and tsunami by predicting and simulating theplate movements of 10, 100 and 1000 years later.

2. A plan of Space observation network in Southeast
Asia
Countries in Southeast Asia have rich natural resources but
they have many natural disasters, too. Thus these countries
have needs of earth observations with observing satellite andinstalling the small ground station to gather and utilize thedesired observing data effectively. The space observation
network can be utilized as the remote sensing exploration or
the observation of natural disasters. Moreover, it is thebenefits of the small ground station that the cost of a
installing is much cheaper than that of the large groundstation.
Meanwhile, in Southeast Asia, the geodetic VLBI
observation network is not existed and the world geodetic
system is not used. However, in these days, most countries
commonly use the world geodetic system as a national
geodetic system. To establish the world geodetic system of acountry, the origin point of national geodetic system should
be determined exactly.

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SOMIRES2013-231th RISH

Development of Bistatic GPS-SAR Image Processing Algorithm
Takuji Ebinuma and Yoshinori Mikawa
The University of Tokyo, ebinuma@nsat.t.u-tokyo.ac.jp
Abstract
Remote sensing using scattered or reflected GPS signals off the Earth’s surface is a new category of satellite
navigation applications. These multipath signals are usually considered to be undesirable signals since they
degrade the accuracy of GPS positioning. However, scattered GPS signals can be utilized as signals of opportunity
for passive remote sensing. This paper presents new synthetic aperture radar imaging process using scattered GPS
signals in bistatic radar geometry and its validation through a field experiment.
Keywords : Bistatic radar, SAR, GPS
1. Introduction
For positioning and navigation applications using GPS
signals, the so-called multipath is one of the major error
sources. In recent years, however, it has been recognized thatreflected or scattered GPS signals off the Earth’s surface canbe applicable for remote sensing1). This new technique isgenerally known as GPS reflectometry (GPS-R). Unlike
most radar-based remote sensing systems that activelytransmit microwave pulses and then detect theirbackscattered radiation, GPS-R utilizes the GPS satellites as
non-cooperative transmitters in bistatic radar geometry.
The scattered GPS signals can also be applicable for
Earth’s surface imaging using synthetic aperture radar (SAR)
approach. Space-surface bistatic SAR (SS-BSAR) is
well-known bistatic SAR model, where it is supposed that a
GPS transmitter is spaceborne and a receiver is located on ornear the surface of the Earth2). SS-BSAR utilizes both thescattered GPS signal and the line-of-sight (LOS) signal
which is received directly from the corresponding GPS
satellite. This approach assumes geometric similarity
between the receiver and the scattering point so that thecorrelation process between the LOS and the scattered signal
could eliminate the dynamics of the GPS satellite motion.
This geometric similarity is, however, no longer valid for ahigh altitude receiver platform such as a low Earth orbit
satellite.
In this paper, we introduce a newly developed GPS-SAR
technique called the quasi-monostatic algorithm (QMA). In
order to overcome the geometric restrictions in SS-BSAR
approach, the range migration curve between the GPS
satellite and the scattered point is modeled as a linear
function. This approximation effectively eliminates thecontribution of the GPS satellite motion in the aperturesynthesis process. QMA is now able to analytically convert
the bistatic geometry into monostatic without any geometricconstraints, and the general range-Doppler algorithm can beapplicable for GPS-SAR data processing. Thus we call thisapproach quasi-monostatic.

2. Quasi-Monostatic Algorithm
While the typical SAR system utilizes a chirp pulse
signal in which the frequency changes linearly with time torealize a wide signal bandwidth, GPS signal is a continuous
wave modulated by the so-called direct-sequence spread
spectrum (DSSS) technique. For example, the typical civilian
GPS L1 signal is modulated with the so-called C/A code. It
can be considered as a pulse signal which has 100% duty
cycle and repeats every one millisecond.
Similar to the general monostatic SAR algorithm,
GPS-SAR time domains can be defined by the fast-time andthe slow-time corresponding to the range and the azimuth
directions, respectively. The range compression algorithm of
GPS-SAR is identical to the auto-correlation process of theC/A code, and the resolution in the range direction is definedby the chip width of the C/A code, which is about 300 m. In
the azimuth direction, the slow-time sampling rate is limited
by less than 1 kHz because the fast-time sample bins should
contain at least one millisecond of signal for auto-correlation
process of the C/A code. This means that the Doppler
frequency should be less than 500 Hz to satisfy the sampling
theorem for the azimuth compression process.
It can also be assumed that the range between the GPS
satellite and the receiver is constant in the fast-time domain.
On the other hand, the effect of the GPS satellite motion is
not negligible in the slow-time domain and appeared in therange migration curve. In QMA, the range between the GPS
satellite and the scattering point is reasonably approximatedby a linear function because the aperture synthesis time ismuch shorter than the orbital period of the GPS satellite.
Therefore, the range rate due to the GPS satellite motion canbe considered constant during the aperture synthesis. Thatmeans the aperture synthesis process in QMA is nearly34

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Fig 1. GPS-SAR UAV platform

Fig 2. Aerial photo of the observation field

identical to that of the typical monostatic SAR geometry.
Detailed description on the point spread function (PSF)
reconstruction in QMA can be found in our early work3).

3. Flight Experiment
A field test of GPS-SAR imaging was conducted toevaluate the QMA performance. A small UAV shown in Fig.
1, equipped with a GPS L1 array antenna and signal capture
instrument, flew over a border of the Ohtone River and its
river bank. Fig. 2 shows the picture of the observation area
taken by the onboard camera, and Fig. 3 shows thecorresponding SAR image. Stronger scattering was
successfully observed from the vegetation on the river bank,while the calm river surface behaved as a specular reflector
and contributed less to the resulting SAR image.
There were a few scattered signals detected fromdifferent GPS satellites, and all of them where observed in
the same range bins. This provided that the movement ofeach GPS satellite was removed properly, and the motion of
the UAV was dominant in the QMA image formulation.
The range resolution of the resulting SAR image islimited to about 300 m, which corresponds the chip durationof the C/A code. This can be improved by using new
wideband civil GSP signals, such as GPS L5. On the other
hand, a much finer azimuth resolution can be achievable by
the effect of the aperture synthesis.

Fig 3. GPS-SAR image in the field test
motion of the non-cooperative transmitter from bistatic SAR
image formulation and can be applied into wider range of
observation scenarios.

Acknowledgements
This research was supported by grant #22686083 fromJapan Society for Promotion of Science (JSPS).
References
1) A. Komjathy, et al., “Developments in Using GPS for
Oceanographic Remote Sensing: Retrieval of Ocean
Surface Wind Speed and Wind Direction,” ION 2001
Technical Meeting, pp. 753-761 2001.
2) M. Antoniou, M. Cherniakov, and C. Hu,“Space-Surface Bistatic SAR Image Formation
Algorithm,” IEEE Transactions on Geoscience andRemote Sensing, Vol. 47, pp. 1827-1843, 2009.
3) Y. Mikawa, T. Ebinuma, and S. Nakasuka, “The studyof the remote sensing application using the GNSS
reflected signal with the aperture synthesis,”
Proceedings of IGARSS 2012, pp. 400-403, 2012.

4. Conclusions
We proposed a new bistatic GPS-SAR algorithm called
QMA, which analytically resolves the constraints on theobservation geometry in SS-BSAR. The field test result
showed that QMA efficiently eliminates the effects of the35

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SOMIRES2013-231th RISHUAVSAR Development Programme in Malaysia
Voon-Chet Koo1, Hean-Teik Chuah2
1Multimedia University, Malaysia
Universiti Tunku Abdul Rahman, Malaysia

2

Abstract
The design and development of Synthetic Aperture Radar (SAR) is one of the focused research areas in Malaysia
since early 2000s. The main objective of this research is to develop an all-weather instrument for earth resource
monitoring. In the initial phase of development, a C-band (5.3 GHz) SAR prototype has been developed forground-based experiments. Its enhanced version, a compact, light weight SAR has been successfully mounted
onto a small unmanned aerial vehicle (UAV) in 2010. Since then, a series of flight missions have been carried out
to acquire radar images for various remote sensing applications. In addition, two new UAVSAR sensors, operating
at L-band (1.27 GHz) and S-band (3.125 GHz) frequency, respectively, have been proposed and currently under
the final stage of development. The former sensor is targeted for landslide and flood monitoring, and the latter for
deforestation monitoring. This paper presents the current progress and the future plan of the UAVSAR sensor development in Malaysia.

36

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SOMIRES2013-231th RISH

Hyperspectral Camera for Microsatellite and UAV
Yukihiro Takahashi 1 and Junichi Kurihara1
Space Mission Center, Hokkaido University, yukihiro@mail.sci.hokudai.ac.jp

1

Abstract
Hokkaido University developed super multicolor imaging system, a kind of hyperspectral camera, using the
LCTF (Liquid Crystal Tunable Filter) technology, which can select any colors with bandwidth of ~10-20 nm
in 420-700 nm or 650-1059 nm at 1 nm step. This multispectral sensor can be applied to various subjects,
such as measuring parameters essential parameters for tropical peatland carbon management, mineral
exploration, fishery and so on. Thanks to its light weight and compact size, LCTF sensor is suitable formicro-satellite with weight of 50-100 kg. Our group will launch 50-kg satellites, namely, RISING-2 and
RISESAT with LCTF telescopic camera in the period of 2013-2014.
Keywords : microsatellite, UAV, payload, super-multicolor, spectral imaging

University Program (1997-2008). Following that, “WildFire and Carbon Management in Peat-Forest inIndonesia” project has been conducted supported by
JST-JICA since 2010 until 2014, collaborated withIndonesian counterparts as LAPAN, LIPI, Ministry ofForestry, University of Palangka Raya/UNPAR andRISTEK. Furthermore, the collaboration between the
Agency for the Assessment and Application ofTechnology (hereinafter referred to as “BPPT”) andHokkaido University, Japan have been established andsigned on August 5th, 2012.
In the meantime, advanced sensors are developed in
Hokkaido University. One of the examples is AMI(Airborne Multicolor Imager) using the LCTF (Liquid
Crystal Tunable Filter) technology, which can select any
colors with ~20 nm bandwidth in 420-700 nm at 1 nm
step. This multispectral sensor is suitable for measuring
parameters essential for tropical peatland carbon
management. Other sensors using the LCTF technology
are installed on the RISING-2 and RISESAT
microsatellites and will be launched in 2013-2014.
Therefore, AMI is positioned as a precursor to the futuresatellite remote sensing of the tropical peatland.
To demonstrate the performance of AMI, the airborne
campaign was conducted on 29th-31th October 2012, inWest Java, Indonesia, using un-manned aerial vehicle(UAV) of BPPT called PUNA. AMI was installed on
PUNA “Wulung”, which has capability to fly using
autopilot to reach area in radius of 70 km and altitude of8000 feet (2.4 km). In this campaign, Wulung flied over
the target location in the peat swamp forest area, about 50
km east of Nusawiru airport. During the flight, AMI
captured a total of 16625 digital images of 420-700 nm at

1. Introduction
Micro-satellite with weight of 50-100 kg has various
merits compared to middle and large sized satellite, that is,1) low cost fabrication compared to middle or large sizedsatellite, namely, few M USD including BUS andmission payloads. The launch cost will be 1-2 M USD as
piggyback, 2) quick fabrication: about one or two years
for flight model would be sufficient, enabling applicationof the latest technologies, 3) on-demand operation, taking
detail information at a point of interest, and 4) the low
cost and quick fabrication make us possible to launch nota small number of satellites and operate them as a
network, which is called as constellation flight. In order tomake the utilization of micro-satellite, the highlyfunctionable advanced optical sensors is essential,
especially in conducting spectral imaging. On the other
hand, UAV (uninhabited airborne vehicle) has a great
potential in measuring local area with higher spatial
resolution than satellite with lower cost as well as “testbed” of spacecraft equipment in developing phase.
Hokkaido University is developing a kind of hyperspetralcamera using LCTF (Liquid Crystal Tunable Filter)
technology. Here we show the initial results of UAV
campaign carried out in Jawa, 2012, and the scope of
application to micro-satellite measurement.
2. UAV campaign
The tropical peatland is a significant carbon reservoir,
but recently it has become a crucial CO2 emission source
due to the wild fire and rapid development works.
Hokkaido University Group has conducted long-term
research at Central Kalimantan’s peatland in close
cooperation with Indonesian experts by JSPS Core

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a 10-nm step with 2 images/sec. Parameters forclassification of tree species in the peatland forest andother land-uses were measured in the area. AMI wasproven to be suitable for Measurement, Reporting andVerification (MRV) using UAV, which is a cost-effective
tool for remote-sensing.
3. Potential of micro-satellite observation
The constellation realizes a frequent monitoring fromthe low earth orbit. If we inserted 100 satellites into
proper orbits, we can watch every location in the worldabout every 3 min. Here we suggest the establishment ofsuch super micro-satellite constellation by Asian
micro-satellite consortium. It’s not easy to launch andoperate more than several tens of satellites by single
country. However, if each country launches 10+ satellites,
the total number could be over 50. On the other hand,each owing countries would like to operate satellites fortheir own purposes. The idea is that the a certain
percentage of machine time of the satellite, for example,
80 percent, is used for their own purposes, but 20 percent
should be remained for public use, such as disastermonitoring or periodic survey planned by international
committee. In order to construct the effective andpracticable constellation, the key would be standardized
remote-sensing payload. One of the examples is the 5-m
resolution telescopic camera with LCTF, which can selectany colors from 420-700 nm and/or 650-1050 nm at 1 nm
step both onboard RISING-2 and RISESAT.
Acknowledgements
The research of UAV observation was carried out by“Wild Fire and Carbon Management in Peat-Forest inIndonesia” project supported by JST/JICA, SATREPS(Science and Technology Research Partnership for
Sustainable Development), Japan. Microsatellite projectis supported by Hodoyoshi project promoted by Cabinet
Office and micro-satellite development project by MEXT
and Kakenhi.

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Modular and Compact Command & Data handling System with Fault-Tolerant Function
for Microsatellite
Dae-soo Oh1, Myeong-ryong Nam1
1
JNM System, Korea, nam@jnmsystem.com
Abstract
This paper describes the design of modular and compact Command and Data handling System (CDS) for
microsatellite. For SEU mitigation Triple Module Redundancy(TMR) and Hamming technology are applied toprotect LEON3 and 8051 IP processors which are implemented in Field Programmable Gate Arrays (FPGAs).
Error Detection and Correction (EDAC) algorithm and memory scrubbing algorithm are also applied to protect
memories. This CDS is on-orbit reconfigurable by uploading FPGA images and Flight Software Code, so thatmodifying and upgrade the system during mission operation are possible.
Keywords : Command & Data handling System, On-Board Computer, Fault Tolerant, Reconfiguration
Leon3 Card

CLVPS

EEPROM

SDRAM

+3.3V
+28V

Dual Leon3-FT

+5V

EMI

DC/DC

+15V

CAN

-15V

MatrixMultiplier

UART

CAN Bus

1. Introduction
There is a trend for high-performance computing andon-board data processing while providing excellent
reliability/SEU immunity.
JNM propose the Command and Data handling System(CDS) as a solution to the space industry’s need forhigh-performance and reliable space data handling system.
The CDS has a feature of a highly modular structure, suchthat it can be quickly and easily configured to most space
applications, such as data processing, communication, andcontrol of various spacecraft subsystems and payloads.

IO Card
EEPROM

SRAM

Payload IO Card
EEPROM

8051-FT
S-band Transmitter
S-band Receiver

Analog Telemetries

Bi-Level Telemetries

SDRAM

Leon3-FT
Encryption /Compression

CCSDS_Tx

CAN

CAN

CCSDS_Rx

UART

UART

Payload I/F

Analog I/F

Digital I/F

MemoryModule I/F

Transmitter I/F

Payloads
X-band Transmitter

Memory Card

Bi-Level Commands
Payloads / Sensors / Actuators

Memory Manager
Payload IO
Module I/F

FLASH
FLASH
FLASH

UART

Fig 1. Configuration of CDS

2. System Design
The CDS is composed of Leon3 Card, IO Card, Payload
IO Card, Flash Memory Card, and LVPS (Low Voltage
Power Supply) Card.
Leon3 Card manages the spacecraft bus and payloads
according to the schedule set by Ground Station (GS) andprovides environment for AOCS (Attitude and Obit Control
Subsystem) Flight Software. Leon3 Card has three Leon-3 IPprocessors and TMR logic. Matrix multiplier for AOCS
software is implemented in FPGA, which allows more stableand fast AOCS calculations.
IO Card has a 8051-FT IP processor which controlsbi-level digital commands and collects onboard digital andanalog sensors data. IO Card communicates with GS
according to CCSDS Protocol and the Protocol IP is
implemented in a IO Card FPGA.
Payload IO Card receives payloads data and transmit themto Flash Memory Card for onboard memory, and sends themto the GS via X-band RF
LVPS (Low Voltage Power Supply) Cards generates low
voltage of +3.3V, +5V +15/-15V.

Payload IO card receives data from payloads and processdata such as RS Encoding, Encryption and Compression.
Flash Memory card has non-volatile flash memories inwhich auto scrubbing algorithm is applied because of SEU
mitigation in space environment
The main features of the proposed CDS are as follows.
(a) Modularity and Compactness
A. Interchangeable Cards Assembly
B. IP Cores of CPU and AMBA Bus in FPGAs(b) Fault Tolerant CPU
A. Three Leon3 processors and TMR Logic
B. 8051 processors protected by Hamming codes(c) Reconfigurability
A. On-orbit FPGA Reconfiguration
B. On-orbit Flight Software update

2.1. Modularity and Compactness
The CDS is designed to provide a high level of electricaland mechanical modularity, while resulting in a very

39

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sensitive area of the micro-controller has been protectedusing the Hamming code technique. This technique is mainly
based on the error detecting and correcting algorithm. In caseof unrecoverable error occurrence, reset signal is
automatically generated and all error event is recorded innon- volatile memory.

compact size. The system utilizes card-to-card stacking with
PCI connectors as an electrical backplane allowing mix andmatch expansion, while CAN bus is used for communication
between Cards. Each Card has aluminum frame formechanical structure and thermal dissipation.
Each Card is designed on SOC concept for compactness.
Most of important functions including CPUs and ARM’s
Advanced Microcontroller Bus Architecture (AMBA[1]) bus
and peripherals as well as external memory controller are
implemented in FPGAs.
The modularity and compactness result in the 3U (100 x
160 mm) size PCB of each Card.

2.3. Reconfigurable Design
FPGA JTAG Daisy Chain

Code Update /FT Manager(M)

User Logic

Code Update /FT Manager(S)

Processor Module

User Logic

Code Update /FT Manager(S)

Payload IO Module

User Logic

Code Update /FT Manager(S)

Memory Module

S-band ReceiverS-bandTransmitter

IO Module

MemoryUser Logic

Fig 3. FPGA JTAG Daisy Chain
Small Satellite electronic components are not available forphysical upgrade or repair after launch. Run-time
Reconfigurable computing technology of SRAM or Flashbased FPGAs allows to overcome this problem. This featureis good benefit for a new generation of low-costcommercial, scientific and military small satellites. For
reconfiguration the IO Card receives FPGA images from GS
and stores them to its memories and reprogram the other
Card via FPGA JTAG which is connected in a daisy chain.

Fig 2. Card-to-Card Stacking type2.2. Fault Tolerant Design
Fault tolerance techniques can improve reliability by
reducing and correcting the faults. In Leon3 Card, three
Leon3 IP cores are implemented in FPGA with TMR logic
which performs voting about the results of the three Leon3
processors, and resynchronize and scrubs the processors.
In IO Cards, Payload IO Card, Flash Memory Card, 8051
micro-controllers are implemented in FPGAs with a VHDL
description protected by the Hamming code technique. The
choice of this micro-controller was based on the fact that it is
widely used in space applications, and consequently, large
amount of data about its behavior under radiation isavailable.

3. Results and Discussion
Modular CDS is a efficient system which can be
configured to most space applications. It is particularly well
suited for small satellites since Cards can be easily beremoved or exchanged, resulting in a only necessaryconfiguration. Fault tolerance feature can also ensure highreliability.
4. Summary
JNM proposed a modular and reliable CDS.

EEPROM
Fault
Injector

Fault
Detector

8051-FT

Fault Control

Acknowledgements
This symposium is sponsored by Center for Environmental
Remote Sensing (CEReS), Chiba University and ResearchInstitute for Sustainable Humanosphere (RISH), Kyoto
University

UART
AHB
UART

APB-3 Wrapper
APB Wrapper

GR-MONSRAM

AHB Wrapper

AMBA AHB BUS
DUT

DUT
APB
BridgeAMBA APB BUS

DUT

DUT

References
1) “AMBA Specification, version 2.0”, ARM Limited, 1999

Fig 3. 8051-FT System
Besides, it makes possible the reuse and protection of all
systems that are already running based on it. The SEU

40

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Implementation of CP-SAR signal processing system on Virtex-6 FPGAKei Iizuka1, Kazuteru Namba2, Josaphat Tetuko Sri Sumantyo3
12

Graduate School of Advanced Integration Science, Chiba University
3
Center for Environmental Remote Sensing, Chiba University
1-33 Yayoi-cho, Inage-ku, Chiba-shi, Chiba, 263-8522 Japan1
k_iizuka@chiba-u.jp, 2namba@faculty.chiba-u.jp, 3jtetukoss@faculty.chiba-u.jp

Abstract
We are developing a microsatellite with a circularly polarized synthetic aperture radar (CP-SAR). In this project
an unmanned aerial vehicle (UAV) of CP-SAR loading is being developed for a preparation experiment prior todevelopment of a micro satellite. To accomplish image processing on the image obtained by the radar, we are
studying image processing system using Field Programmable Gate Array (FPGA). This paper presents a UAV
on-board semi-real-time SAR image processing system. In addition, a sample raw data is processed in theimplemented system and is compared to a data generated on PC, which gives evidence that the designed systemprovides processed image with sufficient high accuracy.
Keywords : microsatellite, UAV, CP-SAR, FPGA

1. Introduction

one-dimensional pulse compression, namely range andazimuth compressions.
The RDA performs FFT, IFFT, and compression using thereference signal for range and azimuth direction. In addition,
the RDA corrects errors caused by the move of the platform[2].

We are developing a microsatellite with a circularly
polarized synthetic aperture radar (CP-SAR). On the
microsatellite, high-speed image processing for very large
data is required. Image processing on the satellite is expected
to reduce image data size and the communication time to theground. From this view point, there are some works forimage processing using Field Programmable gate Array(FPGA)[1].
In this project, we are developing an unmanned aerial
vehicle (UAV) of CP-SAR loading for a preparation
experiment prior to development of a micro satellite. This
paper presents an image processing system designed for the
preparation experiment. The system is implemented on two
FPGA evaluation boards and PC.

3. Implemented system
Figure 1 illustrates the outline of the SAR image
processing system implemented in this work．
This system
consists of two FPGA evaluation boards, ML605 andSP 605, and a PC. The ML605 has a Xilinx Virtex-6
FPGA and 2GB DDR3 DRAM. The SP605 has a Xilinx
Spartan-6 FPGA.

2. Preliminary
2.1. Synthetic aperture radar
Synthetic Aperture Radar (SAR) uses microwave; it isoperable in all-weather and day-night time. SAR
accomplishes to obtain high resolution image; the SAR
virtually made a large antenna by moving a small antenna.

Fig. 1 Outline of the SAR image processing
systemThis system consists of two units: image processing unit
and data storage unit. Raw image data obtained from
CP-SAR are input to the image processing unit throughan AD converter. The image processing unit processes
SAR image processing using image processing system,
and it is configured on the ML605. The processed data is
output to the data storage unit, which is implemented on

2.2. SAR image processing
Raw image data obtained from CP-SAR is unclear; SAR
image gives a clear image. SAR image processing isessential to analyze the image.
The proposed system uses Range-Doppler-Algorithm(RDA) which is a basic method for SAR image processing.
The RDA processes SAR images with two steps of41

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SOMIRES2013-231th RISH

and the MATLAB. We can find that these images arealmost the same; this means that the proposed systemprovides SAR image processing with enough accuracy
for actual use.

the SP605 and the PC. Finally processed data is stored by
the SSD in the PC.
Figure 2 shows the block diagram of the proposed SAR
image processing circuit. The circuit consists of acalculation circuitry, a reference signal storage unit, acorner turn circuitry, a flow controller, a memory
controller, an RX, and a TX. The image processing unit
makes the RDA by performing processing, such ascompression processing and correction processing, on the
raw image data.

Fig. 3 SAR image processed by the FPGA andthe MATLAB
5. Summary
This paper presented an image processing system,
which is implemented on two FPGA evaluation boards
and PC. In the implemented system, a sample raw data
was actually processed and compared to a data generated
on PC, the result of which gave evidence that the image
processing system using FPGA has enough accuracy for
actual use.
However, the implemented system is not capable of
SAR image processing the raw data of 6,144 x 19,904
pixels due to a resource issue; we must resolve it.

Fig. 2 Block diagram on FPGA (Virtex-6 on
ML605)First, data are input from external device, are processedon the calculation circuitry, and are stored in the DRAM.
The data is read out from DRAM, is sent to thecalculation circuitry, is processed, and stored in the
DRAM. Subsequently SAR image data come and go
between the DRAM and the calculation circuitry withbeing processed. During this, the data is processed along
range and azimuth direction in the calculation circuitry,
and reordered in the corner turn circuitry as needed. The
processed data is output to the data storage unit. The RDA
makes six times of range / azimuth FFT / IFFT; theproposed system performs the six by using one FFT
circuit 8,192 points and one FFT circuit of 32,768 points.
The six FFT operations shares two FFT circuitries, which
reduces the amount of used FPGA resources.

Acknowledgements
This work was carried out by the joint research program of
CEReS, Chiba university
References
1) Takuma Kusama, Kazuteru Namba, Josaphat Tetuko Sri
Sumantyo, "Implementation to the Virtex-6 FPGA of the
UAV with CP-SAR image processing system,"Technical Report of IEICE, SANE2012-114, Nov. 2012.
(in Japanese)
2) Kazuo Ouchi, “Principles of Synthetic Aperture Radarfor Remote Sensing,” Tokyo Denki University Press,
2004 (in Japanese)

4. Results and Discussion
A sample raw data was processed in the implemented
system using FPGA in order to evaluate the system. The
size of sample raw data is 2,048 x 1,024 pixels. In
addition the processed data is compared to a data
generated with MATLAB on PC in a proven manner.
Figure 3 shows the SAR image processed by the FPGA

42

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SOMIRES2013-231th RISH

Monitoring Land Subsidence by TerraSAR-X in Cengkareng, Jakarta City, Indonesia
RatihFitria Putri1, Luhur Bayuaji2, JosaphatTetuko Sri Sumantyo1,3 and Hiroaki Kuze1,31
Graduate School of Advanced Integration Science, Chiba University, Japan
2
Faculty of Computer Science and Software Engineering, Malaysia Pahang University, Malaysia
3
Center for Environmental Remote Sensing (CEReS), Chiba University, Japan
E-mail of contact person : ratihfp@chiba-u.jp
Abstract
Subsidence in urban area has the potential to cause severe damage in ecosystem. Therefore it is important tounderstand the subsidence phenomenon in urban area. The objective of this study is to investigate the land
deformation in the metropolitan area of Jakarta, Indonesia using multiple satellite radar imagery. Differential
synthetic aperture radar interferometry (DInSAR) is a technique useful for accurately detecting the grounddisplacement or land deformation in the antenna line-of-sight (slant-range) direction using synthetic aperture radar(SAR) data taken at two separate acquisition times. In this study the DInSAR technique was used to map the land
subsidence in Jakarta region with X-band TerraSAR radar images. A total of 4 TerraSAR-X images acquired from
9 August 2010 to 1 March 2013 over Jakarta were used in this study. The results demonstrated that the land in thearea of Cengkareng was deforming at different rates. Several subsidence bowls with peak displacement rates 10 –17.5 cm/yr along the radar looking direction have been observed Cengkareng.
Keywords : Land Subsidence, Monitoring, TerraSAR-X
1. Introduction

X-Band data to make continuously land deformation monitoring inLand subsidence in urban areas may result in adverse impacts

Cengkareng. TerraSAR-X data provides high spatial resolution ofand can lead to serious problems. Urban subsidence can lead toabout 3 m and has high geometric accuracy imagery. The advantage

increased risk of flooding of coastal areas, severe damage to theof X-Band than L-Band and C-Band is The X-Band has shortbuildings and infrastructures, destruction to local groundwater

wavelength (about 3.1 cm) and confers a high sensitivity to landsystems, and also tension cracks and reactivated faults [1].

deformation. The TERRASAR-X data is the only data that has

Differential synthetic aperture radar interferometry (DInSAR) is a

descending orbit in this study. In this study we would like totechnique useful for accurately detecting the ground displacement orinvestigate land subsidence by applying DInSAR technique. We

land deformation in the antenna line-of-sight (slant-range) direction

processed one pair of TERRASAR-X data between 2010 and 2013.

using synthetic aperture radar (SAR) data taken at two separate

This is the newest available data in this study. The pair, spatialacquisition times [2,3].

baseline and temporal baseline of TerraSAR-X can be found in0

Table 1.

Cengkareng is located between 6 7’9’’S latitude and106043’10’’E longitude, in the western part of Jakarta city. The subB. Geological and Contour Map

A. Study Area

district consists of six regions, covering an area of about 27.93 km2.
Fig.1A shows map of Cengkareng district area on Jakarta City Map.
The area is relatively flat: topographical slopes range between 00
and 20. The elevation of the southernmost area is about 20 m above
sea level, with the other areas being lower (Figure 1B). Cengkareng,
located in the Jakarta basin, has the following five main landforms:
CENGKARENG

alluvial, marine origin, beach ridge, swamp (including mangrove),

JAKARTAand former channel.
JAKARTA

2. Methods
TerraSAR-X is a German high resolution radar satellite program
which will be the first commercially launched on the 15th of June
2007. Until now there is

BOGOR

no C-Band and L-Band has an

operational of advanced SAR-satellite system for scientific andFig. 1. (A) Map of Jakarta basin and (B) Geological map of Jakarta

commercial application for public. Because of that, we used

urban area.

43

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The study area is a newly developed residence area withmore than 300 hundred households living over this area. The
cause of subsidence was predicted as the result of groundwater extraction, the building construction load and humanactivity over this area.

Table 1. TerraSAR-X pair and baseline information
Acquisition Date

TemporalSpatialBaseline

Baseline

Pair

MasterSlave(week)(meter)1

20100809

20110613

44

110.5

2

20100809

20121214

122

149.3

3

20100809

20130301

133

138

4

20110613

20121214

78

39.1

Pair

5

20110613

20130301

89

248.1

NumberMasterSlave

Rate(cm/year)6

20121214

20130301

11

286.3

1

20100809

20110613

17.5

Note: Date are given as year, month, and a day (e.g., 20100809 denotes 9 August220100809

20121214

11.5

2010)

3

20100809

20130301

11.7

420110613

2012121410.0

520110613

20130301

10.5

620121214

20130301

11.8

Table 3. Maximum subsidence and subsidence rate estimation in
Cengkareng by using DInSAR.

3. Results and Discussion
The DInSAR technique result of TerraSAR-X data shows the

Acquisition Date

Cengkareng Subsidence

land deformation is getting larger in terms of area and depth
associate to longer interval time observation. The largest

4. Summary

deformation rate estimation reach 17.5 cm/year in some points

This study shows that DInSAR methods able to detect the groundbased on DInSAR calculation during 44-week interval times.

deformation in Cengkareng sub district area. The DInSAR analysis

Cengkareng, is a settlement area that covers more than 23
km2. Since 2005, flat housing has been widely developed inthis region to relocate the slum dwellers. The international
airport and industrial area were built nearby. The maximum
subsidence rates found during the time span of the study are
17.5, 11.8, 11.7, 11.5, 10.5 and 10 cm/year (Table 2).
20100809-20110613

A

20100809-20121214

B

can be considered as potential tool to monitor the land subsidence
on disaster with low cost, especially to detect ground deformation as
an impact of flood hazard area in 2013. The observation
continuation becomes important to monitor the ground deformationand to prevent further human severe. In the future, multiple aperturetechnique and GPS measurement will be applied to get a better
result and analysis.

20100809-20130301

C

Acknowledgements
The authors would like to thank to PASCO and Center for
Environmental Remote Sensing Chiba University for the financial
support for the research.

20110613-20110301

20110613-20121214

DE

20121214-20130301

ReferencesF[1] A. Primanita, "Jakarta Areas Muara Baru, Cengkareng sinking
Fast," in Jakarta Globe, ed. Jakarta, 2010.
[2] S. Stramondo, C. Bignami, M. Chini, N. Pierdicca and A.
Tertulliani, "Satellite radar and optical remote sensing forearthquake damage detection: Results from different case studies",
International Journal of Remote Sensing, vol.27, no.20, pp. 4433 4447 2006.

Fig. 2. Cengkareng DInSAR result of TERRASAR-X data pair[3] D. M. Tralli, R. G. Blom, V. Zlotnicki, A. Donnellan and D. L.

all pairs mentioned in Table 1. (a) Data pair on 20100809-20110613,

Evans, "Satellite remote sensing of earthquake, volcano, flood,(b) Data pair on 20100809-20121214, (c) Data pair onlandslide and coastal inundation hazards", ISPRS Journal of20100809-20130301, (d) Data pair on 20110613-20121214, (e) Data

Photogrammetry and Remote Sensing, vol.59, no.4, pp. 185-198

pair on 20110613-20130301, (f) Data pair on 20121214-20130301.

2005.

44

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3D Scanner
DM3421AV1/O

Three-dimensional electromagnetic-field distribution measurement system
System

It is large activity to electromagnetic-field distribution measurement of area,and visualization measurement of equipment.
Good three-dimensional measurement and analysis of reproducibility are possible.
■ Three-dimensional vertical plane scanner＆software
AUT

・X-Y-Z axes is controlled freely and wide range electromagnetic-field
distribution measurement is possible.
・Various antennas can be attached.
・superposition of measurement data and a measurement thing photographcan be performed, it can check at a glance.

Software・Automatic measurement of a maximum of 24 waves is possible.
45

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Elevation Positioner

Azimuth Table

Great Circle Test System

MIMO OTA System

Reflective Transmission Measurement System

Portable Anechoic Absorber Wall

46

Antenna Adapter

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SOMIRES2013-231th RISH

The 20th CEReS International Symposium on Microsatellites for Remote Sensing(SOMIRES 2013) and The 231th RISH Symposium
Chiba, 8-9 August 2013
Possibilities of Approach Integrating RS Multi-Data Analysis and GIS for Water Resources Managementand Environmental Monitoring

The case study of Bili-Bili Irrigation System, Indonesia
Yaqien Gisno Ogalelano1, Takao NAKAGIRI2, Hiroki OUE3, Dorotea Agnes RAMPISELA4, Sartika LABAN5,
Hisaaki KATO6
1

Ehime University, Hasanuddin University, E-mail: yaqien7@yahoo.com, 2Graduate School of Osaka Pefectural

University ,3Graduate School of Agriculture, Ehime University , 4Department of Soil Science, Hasanuddin University, 5Ehime
University, 6Research Institute for Humanity and Nature.

Abstract
The use remote sensing and Geografic Information System (GIS) datas allow more efficient analysis because thetemporal and spatial dimensions could be studied at once, especially to generate primary data on irrigated area, cropping
pattern and crop yield at disaggregated level and to access the improvement in agricultural productivity and water
management in canal irrigation schemes. Another issue in the spatial and temporal dimension of water productivity. A
spatio–temporal analysis could broaden the role of models in exploring improved water use in agriculture. The GIS
technique helps in integration of satellite data and ground information to evaluate the distribution water performance andto diagnose the inequality in the performance to aid in improving the water management. This paper aims to improve
agricultural productivity, water productivity, and environmental monitoring through a predictable, equitable and reliable
irrigation service.
Keywords : Integration of RS and GIS, Multi data analysis, Water resources management, Environment, Monitoring
1. Introduction
According to Rampisela (2011) The Bili Bili Dam, which
completed construction in 1999, has the capacity to store 375
million m3 of water. Although the primary objectives of the dam
are flood control and clean water supply for makassar urban area
and its surrounding environs, the dam also proves capable ofproviding irrigation for 25,472.16 ha of rice fields (fig. 2(A).
Almost every year in irrigated areas of Bili-Bili especially inthe lower reaches during the dry season, farmers didn’t get water
for irrigation. Many problems which is influence the insufficientwater in irrigation canals, such as canals damage, water lost to
pond (eks making brick), and water gate uncontrol).
The integration of remote sensing and Geographic
Information Systems (GIS) has received considerable attention
in the literature. Ehlers et al. (1991) first reviewed the necessityof integrating remote sensing with GIS, and discussed thepotential of integration in water resource management andenvironmental monitoring.
In this paper we will discuss about possibilities approach
integrating remote sensing multi data analysis and GIS to
manage water resources and environment with 2 indicators, thatis water availability and cropping patterns. Remote sensing multi
data analysis means using variety of resolution data analysis
from different sensors (fig. 1).

2. Methods
This research will survey (ground truth; observation, interviews,
crop photos time series from few location), spatial analysis, timeseries analysis, statistical analysis, and collecting data (weather
data from on site meteorological station, secondary data from
BPS and etc)

Fig.1. Approaches of integrating RS multi-data analysis
and GIS Scheme
3. Results
We successfully to extract data from Ikonos (Fig.2) and Modis

47

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Graph.1. On site measuring data and secondary data in Kampili
Irrigation Area (A) Water use of green beans during Dry season(August to November). (B) Rainfall data in 2001 and 2010 fromBPS (Central bureau of statistics).
After that, we will validation with ground information which
extract from water use data analysis ,weather data (graph.1) andground survey, then we collect all data in data bank using GIS
analysis.

data analysis (Fig.3) and now, we will try to Landsat 8 OLI andSAR data analysis to get more information about water
resources and environment condition in Bili-Bili Irrigation
System.
Ikonos data analysis
A

B

4. Discussion
One of the main advantages of this integrate is its capability
to monitoring water resources and environment and easy to
making the best management plan. The other hand, we want totry about using SAR and CP-SAR images from microsatellite tomonitoring environment problem like the subsidence andground water problem issue in irrigation area. This is the main
problem issue for future because, we can see of human activity
especially farmers exlore water from ground water in dry season
to be increase every year.

Fig.2 (A) Study site location, South Sulawesi, Indonesia. (B) Extractionof Ikonos data for spatial data analysis to observe the current
situation with more accurate

Modis data analysis

5. Summary
In this paper, we proposed to develop a new approach
integrating remote sensing data analysis from different
resolution and sensor data. This is integrated will be applicablefor irrigated area mapping, cropping pattern management, waterrequirement, and disaster monitoring. We also proposed theSAR image data for environmental monitoring at Bili-Bili
Irrigation area..

A

B

Acknowledgements
This Research is part of Water Resources Management Project(C-09-Init) funded by Research Institute for Humanity andNature (RIHN), Kyoto, Japan. The authors would like to thankthe Pelangi Agency of Makassar that provide the bili-bili
irrigation system dataC

Fig .3. Validation of the underestimated number of crops in 2001, 2010

References[1] Ehlers, M., D. Greenlee, T. Smith, and J. Star, 1991.
Integration of remote sensing and GIS Data and data
access, Photogrammetric Engineering b Remote Sensing,57(6):669-675.
[2] Rampisela D. A. 2011. Bili-Bili Irrigation system. Bili-Bili
Irrigation Project. South Sulawesi, Indonesia.
[3] OUE H., Sartika L., D. Agnes Rampisela.. 2013.
Evapotranspiration and Water Balance In A Water Use
Association Block Area In South Sulawesi During The
Dry Season. Water Management Project.

and 2011 in Bili-Bili Irrigation Area, South Sulawesi, Indonesia (A) EVI
MODIS false-color image (R:G:B= Band 6: Band 2: Band 1). (B)Kampili Irrigation Area (MODEL). (C) Average monthly EVI MODIS
data in areas where the almost every year insufficient water and numberof crops per year decreased in 2010 to 2011 and also we compare within2001 to 2010 which purpose to know about the copping pattern before
and after landslide.

Water use analysis
A

B

Source : Sartika & Oue data, 2012

Source: BPS data, 201148

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Preliminary Study of Concrete Surface Temperature Mapping on Structure Problems in
Makassar City with Airbone Thermal Remote Sensing
Arwin Amiruddin1, Josaphat Tetuko Sri Sumantyo1, Ilham Alimuddin2, Merna Baharuddin3
1Hasanuddin University, 2Chiba University, a.arwinamiruddin@yahoo.com
Abstract
Nowadays, the corrosion of concrete structures has moved into attractive fast-growing research. Corrosion in
concrete is influenced by water, air, and temperature. Especially for the influence of temperature, this preliminary
research will focus on mapping the temperature of concrete surface. Objective of this study is to develop atemperature mapping on concrete structures through airborne thermal remote sensing. The research will located at
Makassar city in South Sulawesi, eastern part of Indonesia. Due to the research is still preliminary so the study
was limited to the characteristics of the existing concrete building in Makassar city related with a remote sensing
perspective. Results of this study are expected to assist the local authorities for early detection of corrosion
problems on concrete structures and possibly will prevent a significant amount of structural failure and loss. In
future, the shadow effect on radiant temperature will analyzed. The statistical T-test will used as measure in
detecting concrete surface and provided to be effective.
.
Keywords : concrete surface, thermal, mapping, makassar city
thermal remote sensing data for mapping concrete structureanomalies in detecting temperature differences.

1. Introduction
Makassar city is one of major cities in Indonesia and is located ineastern part of Indonesia. Based on data from the Meteorology,
Climatology and Geophysics Region IV Makassar that rainfall in
Makassar, South Sulawesi and other regions are generally
categorized overcast-light rain with temperatures between 23-32oC,
humidity of 63-97%, and the average wind speed ranges from 2.9
knots. Because Makassar city is in the tropics region so thetemperature is a few things to consider. Infrastructure in thecity is an average made from concrete, therefore, the effectof temperature on the concrete / concrete surfaces need to betested for early detection of damage of concrete structuresand for the purpose of maintenance of them.
Figure 1 shows the Makassar city as the location of study.
There are many concrete construction that stands such as
hotels, offices, and others. In addition to temperature effects,
the location of Makassar city is near the sea causing
corrosion effects become important for concrete buildings.
A series of studies have been studied related to the
corrosion problems in concrete buildings, such as theinfluence of sea water to coastal structure buildings (Arwin,
et al, 2012). However, this research takes a long time so itneeds to be done similar research through the perspective of
remote sensing using airborne thermal remote sensing.
Through this approach it is expected that it will be able tomapp the temperature on the concrete surface and early
corrosion can be detected so that possibly will prevent asignificant amount of structural failure and loss.
In this study, we investigate the applicability of airbone

2. Methods
Makassar city is located in the plains near the sea ineastern part of Indonesia. Recently, infrascture developmentusing concrete material is incessant carried out in Makassar
thi is consideration choosing this location as objects of study.
Thermal Airbone Broadband Imager 320 (TABI-320), a
new airbone thermal sensor developed by ITRES ResearchLtd. (Canada), was acquired by PASCO Corporation (Japan).
The specifications of TABI are shown in Table 1.
The study will be divided into 2 (two) parts, namely, inearly morning (EM) and in early afternoun (EA). The data
will be recorded from flight record of TABI for acquiring thethermal data with 1.5m Ground Sampling Distance (GSD).

Study Area

Fig. 1 Makassar city as location of study

49

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Where

The study area covers 0.67 km * 7.2 km. These images
were orthorectified with a 50 m resolution DEM (Digital
Elevation Model) released by Geographical Survey Instituteof Japan.
Table 1. Specifications of TABI-320
Instrument TypePushbroom Thermal Imaging Microbolometer48 deg across-track across 320 pixels; ~f/1

Field of View (FoV)
0.25 deg along-track
Instantaneous Field of View

2.87 milliradians

Spectral Range

8 – 12 m (800 – 1200 mm) : 1 band

Dynamic Range

4096 : 1 (12 bits)

Temperature Range-20 to 110 oC Nominal

NEt

0.1 K

if |ZsAnp| or |ZsMnp| is greater than 1.96 (95% confidence
interval), the pixel will be discriminated as a concrete
anomaly point.

In general, the temperature of each surface cover increases
after sunrise, continues to increase until 2:00 PM, and thendecreases gradually. The temperature deviation depends on
surface cover type. Thermal image has a great possibility forconcrete monitoring because the deviation of concretesurface temperature in one day is large. We assume that theirregular distribution of temperature occurs at the concrete
anomaly points.
In general, the radiant temperature observed by
spaceborne / airbone thermal sensors is easily affected byshadow, especially on the high resolution images. Therefore,a shadow simulation with DEM could be useful to estimate
and remove its effect. However, the 50 m resolution DEM
available in this study is unsufficient to simulate the shadow
area of the 1.5 m GSD thermal images. Instead of DEM , 2
TABI images in early morning and in early afternoon wereused to estimate the shadow effect.
The difference of the the radiant temperature (T) was
defined as below.
T = TEA - TEM

3. Results and Discussion
Due to the study is still preliminary, the results have notbeen obtained yet. However, this preliminary study is the firststep to start analyzing the effect of temperature changes on
the concrete surfaces in Makassar city.
4. Summary
The temperature deviation depends on surface cover type.
Thermal image has a great possibility for concretemonitoring because the deviation of concrete surface
temperature in one day is large. We assume that the irregular
distribution of temperature occurs at the concrete anomaly
points.
Acknowledgements
I would like to express my gratitude to Prof. Josaphat Tetuko
Sri Sumantyo for his valuable help. Also, many thanks to
Hasanuddin University through JIBIC Loan for financial
support to participate in the short term research at Remote
Sensing Laboratory, Chiba University for 3 (three) months(July – September 2013).

(1)

Where TEA is radiant temperature from the early afternoon(EA) image, TEM is radiant temperature from the earlymorning (EM) image.

References
1) F N. Karanja, S. Matara, 2013. The Transformation FromGreen to Concrete Cities; A Remote Sensing Perspective,
International Archives of The Photogrammetry, Remote
Sensing and Spatial Information Sciences, Volume
XL-1/W1. ISPRS Hannover Workshop 2013, 21-24 May
2013, Hannover, Germany.
2) Karen Fletcher, 2007. InSAR Principles: Guidelines for
SAR Interferometry Processing and Interpretation.

For a statistical interpretation of concrete anomaly, theT-test is proposed to detect the temperature anomaly at peach
pixel.
Zstnp = Xstnp - Mst / stZ : statistical score
X : radiant temperature of the pixel of the pixel
M : mean value of the radiant temperature of
normal concrete : standard deviation (STD) of the radiantemperature of normal concretes : shadow condition (N:NS, M:SM, A:SA,
B:SB)t : observation time (A:EA, M:EM)n : number of line (1,2,3)
p : pixel position (-2, -1, 0, 1, 2)

(2)

50

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Array of Triangular Microstrip Antenna and Combined Triple Rectangular Microstrip
Antenna for Radio Altimeter and Ground Penetrating Radar
Merna Baharuddin1, Elyas Palantei1, Zulfajri B. Hasanuddin1, Rusli1, Andi Azizah1, Josaphat T. Sri
Sumantyo2
1
Dept. Of Electrical Engineering, Hasanuddin University, INDONESIA,
2
Microwave Remote Sensing Laboratory, Chiba University, JAPAN,
merna@unhas.ac.id
Abstract
This study presents microstrip antenna developments for GPR and radio altimeter applications. An array of
triangular antenna is designed for radio altimeter in the frequency of 4,25 GHz. A shape of combined triple
rectangular microstrip antenna is designed for GPR appilication in the frequency of 1 GHz. Design and simulation
was conducted using the software Ansoft High Frequency Structural Simulator (HFSS) V.13. Then the design iscreated in the form of prototypes by using Printed Circuit Board (PCB) made of FR4-Epoxy which has a thicknessof 1.6 mm and a dielectric constant of 4.4. The measurement was done using a Vector Network Analyzer E5071C
ENA and ED 3200.
Keywords : microstrip antenna, radio altimeter, ground penetrating radar
2. Methods
The microstrip antennas have the form of triangular array and a
combined triple rectangulars.. Design and simulation is done using
HFSS V.13 software. By this software, then obtained shape and size
dimensions desired of the microstrip antennas. Antenna prototype ismade based on the shape and size dimensions of microstrip antennas
that have been obtained from the HFSS v13 software. The design
was done by making the antenna design in three dimensions. The
dimensions of the designed antenna design are made in accordancewith the results of mathematical calculations. After three
dimensional antenna design has been established, next step ismaterial selection. The patch, feed and ground plane, the materials is
perfect-E, for substrate the material is FR4-Epoxy (relative
permitivity (εr) 4.4, Dielectric loss tangent (tan δ) 0.2, substrate
thickness (h) 1.6 mm), while air is used for the boundary.

1. Introduction
A radio altimeter [1] is a device, which is used to measure a low
altitude or distance from an aircraft or spacecraft to ground surface or
to a sea level. This distance is calculated under the craft in verticaldirection. Radio altimeter is a part of radar. The working principle ofradar is, it transmits radio waves towards ground level or sea level
and receives an echo signal after time duration. This value of time isdepending on speed of the vehicle and height between craft (air orspace) and ground. Radio altimeter is working in the band of
4.2GHz to 4.4GHz
Ground Penetrating Radar (GPR) systems [2] are used for the
subsurface investigation of earth. They are used in the detection of
objects buried beneath the earth surface such as pipes, cables, landmines, and hidden tunnels. A GPR system consists of a transmitting
antenna and a receiving antenna. The transmitting antenna isconnected to a source and the receiving antenna is connected to asuitable signal processing device. It is required to develop efficient
GPR antennas to satisfy a number of demands. A GPR systemshould have low and short coupling between transmitting andreceiving antennas to avoid false detection. Since it operates very
close to ground, its characteristics should not be affected strongly
with ground properties
This study presents microstrip antenna developments for
GPR and radio altimeter applications. An array of triangularantenna is designed for radio altimeter in the frequency of
4,25 GHz. A shape of triangular of a microstrip antennapreviously has been investigated for CP SAR [3]. A shape of
combined triple rectangular microstrip antenna is designed
for GPR appilication in the frequency of 1 GHz.

Fig. 1 Designed Array of triangular microstrip antenna
and the fabricated prototype.

Fig. 2 Designed Combined triple rectangularmicrostrip antenna and the fabricated prototype.

51

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SOMIRES2013-231th RISH

Tabel 1 Microstrip Triangular Array Dimension
Triangular patch driven

Triangular side length (a) = 26,14

element

mm, Height (t) = 18,01 mm

Reflector Size

Longer 0,3 cm than the driven

3. Results and Discussion
Prototype microstrip antennas were measured using
Antena Trainner System ED-3200 and Network Analyzer
Agilent 5017C. This measurement is done in the
Laboratorium of Telematika Electrical Engineering
Department Hasanuddin University.
For the array of triangular microstrip antenna, thebandwidth obtained from the measurement is 270 MHz in
the 4,25 GHz frequency. Further measurements are
conducted to obtain the radiation pattern, and gain. Testing tomeasure height from certain position off the ground as thisantenna will be applied for altimeter.
For the combined triple rectangular microstrip antennas,
the bandwidth obtained from the measurement is 22 MHz in
the 1 GHz frequency. Further measurements are conductedto obtain the radiation pattern, gain, and S21 parameters. As
this antenna will be applied for GPR, the testing with certain
soil depth using 2 antennas, one as transmitter and another asa receiver, will be conducted.

element , Triangular Side Length (a)= 32,14 mm, Height (t) = 21,01 mm
Director Size

Shorter 0,1 cm from the driven
element, Triangular side length (a) =24,14 mm, Height (t) = 17,01 mm

Distance between reflector

D1 = 0,2λ = 14,117 mm

and driven element
Distance between 1 andD2 = 0,4λ = 28,235 mm

driven element
Distance between director 2

D3 = 0,8λ = 56,470 mm

and director 1
Distance between director 3

D4 = 0,05λ = 3,529 mm

and director 2
Distance between director 4

D1 = 0,05λ = 3,529 mm

and director 3

4. Summary
An array of triangular microstrip antennas (4,25 GHz) anda combined triple rectangular antenna (1 GHz) has beendeveloped for radar altimeter and ground penetrating radar
respectively. The simulation and measurement results haveshown good results. Further measurement and testing will be
conducted and more improvement on the antenna systems
will be applied.

Tabel 2.Microstrip Combined Triple Rectangular Dimension
Dimension Part

Size (mm)Wtrc (wider side ) patch

48,5

LMAX patch113

Wg (width) groundplane

120,71Lg (length) groundplane

120,54d (diameter) feed point hole

1.27

Xf (coaxial Feed)

16,61

Acknowledgement
Authors would like to express gratitude to Faculty ofEngineering, Hasanuddin University, through the JBIC Loan
for the opportunity to participate in the short term research
program.

The design of the antennas from the mathematic
calculation of its dimension apparently not giving the desired
results. Therefore, the optimization process is carried out by
varying the dimensions of the components of Microstrip
Antennas. Changes in patch dimensions, length and width of
the feed, the dimensions of the ground plane and substratedimensions provide significant changes to the antenna
parameters.
Process optimization is done by numerical experimental
to obtain the results as expected. From the optimization
process final dimensions of designing an array antenna
Microstrip Triangular and a combined triple rectangulars are
obtained as shown in Table 1 and Table 2 . The final shape of
the array triangular Microstrip Antenna and combined triple
rectangular that are simulated in HFSS v13.0 are shown in
Figure 1 and Figure 2.

References[1] Wideband Partially-Covered Bowtie Antenna for
Ground-Penetrating-Radars, G. E. Atteia, A. A. Shaalan,and K. F. A. Hussein, Progress In Electromagnetics
Research, PIER 71, 211-226, 2007
[2] Asghar Keshtkar, Ahmad Keshtkar, and A. R.
Dastkhosh, “Circular Microstrip Patch Array Antenna
for C-Band Altimeter System”. International Journal of
Antennas and Propagation Volume 2008.
[3] Merna Baharuddin, Victor Wissan, Josaphat Tetuko Sri
Sumantyo, and Hiroaki Kuze, “Equilateral Triangular
Microstrip Antenna for Circularly-polarized Synthetic
Aperture Radar,” Progress in Electromagnetics
Research (PIER) C, Vol. 8, pp. 107-120, June 2009.

52

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SOMIRES2013-231th RISHFPGA BASED MULTIPLE PRESET CHIRP PULSE GENERATOR FOR SYNTHETIC
APERTURE RADAR ONBOARD UNMANNED AERIAL VEHICLE SYSTEM
Kyohei Suto1, Josaphat Tetuko Sri Sumantyo1, Cheaw Wen Guey2 , Koo Voon Chet2
1

Center for Environmental Remote Sensing, Chiba University,
1-33 Yayoi, Inage, Chiba, 263-8522 Japan, z9t1541@students.chiba-u.jp
jtetukoss@faculty.chiba-u.jp
2
Faculty of Engineering & Technology Multimedia University
Jalan Ayer Keroh Lama, Bukit Beruang 75450 Melaka, Malaysia, wengueyc@gmail.com
vckooo@gmail.com

Abstract
Synthetic Aperture Radar (SAR) is one of active microwave radar sensor that could work all weather andday/night time. This system can transmit and receive the pulse to and from observe objects on ground surface,then its detailed figure or water vein location, output result as a microwave image could be obtained after some
SAR image processing. SAR sensor needs special modulated signal especially chirp pulse for realization of highresolution and precise image. But, in the case of Unmanned Aerial Vehicle (UAV), Observation condition isalways varying during flight or mission, therefore So some pulse parameter, like a i.e. bandwidth, and pulse
duration, PRF etc, should be changed to adequate value each time simultaneously. This paper shows first stepresearch of it, base chip pulse generator which can switch some preset output chirp signal. This paper discusses
the proposed FPGA variable based Chirp pulse generator to solve the platform posture effect on our UAV SAR
mission.
Keywords : SAR, UAV, FPGA, Chirp pulse
1. Introduction
whole earth environment, including climate, temperatureand land coverage is changing day by day. Recently, so
called global warming problem accelerates theseenvironmental changes. Of course this matter has potent
influence on our human living, and sometimes appears as adisaster or any other environmental problem. So we must
know two important factor about this environmental changes,
precise detail of environmental changes and reason of it.
Tectonic plate movement is key factor to understandenvironmental changes. Movement of tectonic plate neverstop as long as all volcano on earth keep alive. It not only
causes continual land deformation, but also has influence on
our lives, land coverage, sea stream and climate. Earthquake
is also one of the phenomenon caused by tectonic platemovement.
As well known, earthquake gives serious
damage to our lives in some country, especially located area
called ring of fire around pacific ocean because the damage
area is huge and we can't inhibit it. Therefore many
researchers tried to manage to predict earthquake somehow.
And recently, some method for earthquake prediction are still
under research. We are also researching the relation between
land deformation and earthquake. We use the microwave
remote sensing technique to observe land deformation53

because microwave radar can get figure information which
has only earth surface figure without any buildings and land
coverage. Microwave radar which mounted on airplane orsatellite can observe very vast area in short time so it'sadequate for regular surveillance. Synthetic aperture radar
called SAR is most popular system of microwave radar.
SAR equips small and multiple separated antenna to improve
resolution of observation, and generate one synthesis datafrom all data of small antenna as if getting from one hugeantenna. In this system, resolution of range direction depends
on signal characteristics used for observation. The more wide
Frequency band become or the more higher pulse duration
become, The more higher resolution also become. Therefore
SAR system uses chirp signal which continuously changes
its frequency as observation signal. When we use chirp signal
for SAR system observation, we must consider to set someparameters of chirp signal because the most appropriate
parameter of it depends on observation situation. Especially
SAR which mounted on airplane is under very unstablecondition, so we suggest to change the chirp signal
parameters even during observation for more precise result.
Therefore I tried developing chirp pulse generator which canchange output signal parameters by using digital circuit
which consists of FPGA and DAC. This device will use in

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SOMIRES2013-231th RISH

our SAR system to validate effectivity later, and in future I'll
improve this to be able to change output in stand alone.

2. Methods
I designed chirp signal generator by using reconfigurable
device, FPGA because it can make the time to configure
and validate more shorter. I used two device, FPGA
development board DE2-115 and data conversion card
including DAC distributed by Terasic. (fig.1)

3. Results and Discussion
Output signal waveform is shown in Fig 3 below.

(a) Preset-1 chirp signal(b) Preset-2 chirp signal
Fig. 1 FPGA development board and DAC card
I designed chirp signal generator by Direct Digital
Synthesizer(DDS) method because this method is easy tochange the output. This method uses both Tuning word
LUT (Phase step value) and sine-wave LUT(amplitude
value) to generate chirp signal. This time I set signal and
DDS parameters as shown in Table 1 below. And whole
logic structure is shown in Fig 2.

Table. 1 Parameters of signal and DDSParameter

Preset-1

Preset-2

Preset-3

Band width

30MHz

50MHz

100MHzPulse duration

0.5us

2.0us

4.0us

Number of sample

125

500

1000

Sampling rate

250MHzQuantization bit

14bit

PRF

1000 pulse /s(c) Preset-3 chirp signal
Fig. 3 Preset chirp signal on oscilloscope
4. Summary
This is just result as a signal output. This means that theeffectivity is not validated definitely. Therefore I must
validate it by actual observation using SAR system andthis device.
Acknowledgements
I would like to express the deepest appreciation to mysupervisor, Prof. J. T. Sri Sumantyo, Prof. V. C. Koo, Mr.
W. G. Cheaw, and many researchers of Malaysia
Multimedia University.
References
1) J. T. Sri Sumantyo, V.C.Koo, 2012. Development of Circularly
Polarized Synthetic Aperture Radar onboard UAV for Earth
Diagnosis.
2) J. T. Sri Sumantyo, 2012. Development of Circularly Polarized
Synthetic Aperture Radar Onboard Unmanned Aerial Vehicle(CP-SAR UAV).
3) M. Y. Chua, V. C. Koo, 2009. FPGA-Based Chirp Generator
For High Resolution UAV SAR

Fig. 2 Block diagram of whole chirp generator

54

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SOMIRES2013-231th RISH

Microwave dielectric constant measurement of arid soil in the 0.3-3 GHz frequency range andinterrelationship with land cover and soil types
Saeid Gharechelou1, Ryutaro Tateishi2, Josaphat Tetuko Sri Sumantyo3
1- PhD student, CEReS, Chiba University, Japan, e-mail: acfa3286@chiba-u.jp.
2- Professor, CEReS, Chiba University, Japan.
1-33 Yayoi-cho, Inage-ku, Chiba-shi, CEReS, Chiba University, Japan, post code: 263-8522.

Abstract
Arid soils occupy around 12% of the Earth's ice-free land area. Aridisols are used mainly for range, wildlife, andrecreation, because of the dry climate in which they are found. There are several methods to measurement the soil
moisture in field and in laboratory experiment such as the dielectric constant and microwave remote sensing, thetime domain reflectance (TDR) and gravimetric method. The purpose of this paper is to develop expressions forcharacterizing of the relative dielectric constant of arid soils in the 0.3-1.3-GHz frequency range and it
interrelationship with soil types and land cover. In this study the first tried to took the field sample from top soil
(0-15 cm) in homogeneous area in land unit map which provided in environmental GIS data base in arid region of
Iran, and then measurement the dielectric constant at microwave remote sensing laboratory for investigation thecharacteristics and behaviors of dielectric constant of arid soil with variety of moisture content and soil fraction in
0.3 – 3 GHz frequency range. The result of dielectric constant properties has shown the soil types after the
moisture content has most affected on the constant and then soil salinity. Land cover also has good agreement bydielectric constant in each level of soil moisture content even in same soil type, for example sparse vegetation andbare land both was in clay soil type but sparse vegetation recorded higher dielectric constant than bare soil. For
soil salinity observed the in same soil type and moisture content saline soil has shown higher constant.
Keywords : microsatellite, UAV, payload, mission
area in land unit map which provided in environmental GIS
data base in arid region of Iran (Fig.1). Then measurement
the dielectric constant of 40 soil samples at microwave
remote sensing laboratory using dielectric constant tool kit ofAgilent model. The measurement of dielectric constant downin 3 steps by change the moisture constant of each samples in
the natural soil, dried soil and saturated soil finally oven soil
(Fig.1). Thus, all data analyzed by integrated to other geo
physical data in GIS such as land cover and soil type and soil
salinity. Finally all data related to each sample position as
spatial extracted in ArcGIS software and export to excel forstatistical analysis.

1. Introduction
Soil moisture plays the important role in environmental
science such hydrology, agriculture, meteorology, etc. Aridsoils occupy around 12% of the Earth's ice-free land area.
Aridisols are used mainly for range, wildlife, and recreation,
because of the dry climate in which they are found. There areseveral methods to measurement the soil moisture in field
and in laboratory experiment such as the dielectric constantand microwave remote sensing, the time domain reflectance(TDR) and gravimetric method. In microwave soil moistureremote sensing determining the soil moisture by measured
the value of dielectric constant is important, because theemissivity and back scattering coefficient of soil at eachfrequency is simulated and then driving the soil moisture on
ground surface using satellite data. The dielectric constantdepends on the type of material as well as its moisture state.
The study area is located in arid area of Iran in northern partof central desert. The purpose of the study presented in thispaper is to develop expressions for characterizing of therelative dielectric constant of arid soils in the 0.3-1.3-GHz
frequency range and it interaction between soil moisture
content, soil types and land cover.
2. Methods
In this study the first was tried to take the field sample
from near top soil (0-15 cm) using GPS in homogeneousFig.1. Field work in sparse vegetation, bare land for soil
sampling and laboratory experiment55

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SOMIRES2013-231th RISH

types it seems the vegetation has important role tosoil developing process and soil texture which it can
influence to dielectric constant, for example sparsevegetation compare with bare land in study area
show the higher dielectric constant (Fig.3) .

3. Results and Discussion

I. Dielectric measurement for the 0.3-1.3-GHz range
We was measurement more than 520 times for 40
samples of e' and the same for e" were madecovering the range from 0.3 to 1.3 GHz especiallyfor 1.27 GHz set on ALOS PALAR frequency for
four soil types of sandy, silt, clay and loam undervarious moisture conditions. The first step in theanalysis of the data was to compare the measured
values with those calculated on the natural soil
basis of the e’ and e’’ outlined the dielectric
constant tool kit (Fig.2).

Fig.3. Dielectric constant properties and relationship in
different moisture content, soil types and land cover.

4. Summary
The result of dielectric constant properties has shown the e'
Fig.2. Shows measured values of e' and e" plotted at the
0.3-1.3-GHz range.

very sensitive than e" to soil moisture particularly forsaline soil which could detect clearly. Soil types after

II. Dielectric dependency on soil types and landcover
The dependence of e' and e" on soil types
composition (sand, silt, and clay) is a result of therole played by water storage in soil fraction
particularly as boundary of soil particular. In the
research, the soil types are comprised of four
components: clay, silt, loam and sand andinterrelationship with different land cover types andstorage of water inside the soil that we could
observed it. The total water volume fraction (m)which affected directly on dielectric constant
between soil saturated condition and bound waterin wilting point is administered by the specificsurface area A (in m2 /g) of the soil particles. The
surfaces (A) composed predominantly of clay thatit depend directly to soil particle size and texture forexample sandy soil has much more than clay soil. At
result clay soil has more particle surface and could
reserve much bound water and show the highdielectric constant than sandy soil, however otherparameter such soil organic material and mineral areaffected on it.
According to land cover types and interaction to soil

the moisture content has most affected on the constant andthen soil salinity, however the moisture content also
dependent on soil texture and soil types. Land cover also has
good agreement by dielectric constant in each level of soil
moisture content even in same soil types. This information
might be useful for backscattering simulation and modeling.

References
E. Lee, T. N. Chase, B. Rajagopalan, R. G. Barry, T.
W. Biggs, and P. J. Lawrence, Effects of irrigationand vegetation activity on early Indian summer
monsoon variability, International Journal of
Climatology, 573-581. 29 (2009).
2) Gadani . D. H., Vyas, A .D. Measurement ofcomplex dielectric constant of soils of Gujarat at Xand C-band microwave frequencies, Indian Journalof Radio & Space Physics ,Vol. 37, June 2008, pp.
221-229.
3) Marttit, aillikainen, Fawwaz T. Ulaby, Myron C.
Dobson, Mohamed A. El-Rayes, and Lin-Kunwu,
Microwave Dielectric Behavior of Wet Soil-Part
1:Empirical Models and Experimental Observations,
IEEE Transaction Geoscience and Remote Sensing,VOL. GE-23, NO. 1, January. 1985.
1)

56

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SOMIRES2013-231th RISH

The COTS-based Micro Earth Sensor(MESA) for small satellite to
The Symposium on Microsatellites for Remote Sensing (SOMIRES 2013) and
The 231th RISH Symposium
Kazuo Tanimoto , Takanobu Omoto(Meisei Electric)
Hiroshi Tachihara(JAXA)
Takanobu Omoto ,omotot@meisei.co.jp
Abstract
We introduce the COTS thermopile –based Earth Sensor(MESA) for Small Satellite .It have been developed by
Japan Aerospace Exploration Agency (JAXA) ,and We Meisei Electric co.,ltd have took charge ofelectronics .The thermopile sensor is very popular for security and hearth equipment ,then it can be used with low
cost and short delivery time .MESA has I2C interface for space craft system ,the electronics is very simple ,verl
low power and very small size . It make the developing for space use altitude sensor low cost ,minimized
developing schedule and very low resource . The 4pieses of multi-pixel array of thermopile are used for MESA ,In fundamental developing phase , MESA have been tested and verified that it’s performance is fine to detect
Erath edge for satellite altitude control , and also the Flight Model complete now ,The Flight model is now in
integration for Small satellite “SOCRATES” and it will be launched in 2013 .
Keywords :COTS thermopile ,Earth sensor, Small satellite
1. Introduction
The Earth sensor is one of altitude detection sensor for
spacecraft and it is good performance sensor for Earthpointing satellite such as Earth Observation Mission . There
are some Earth sensor for space use ,but all of them are large
size and high cost because of these have been developed forlarge size space craft .The small satellite has possibility tomake activation of use of space ,especially Erath observation .
The Erath sensor which is small size ,low cost and shortdelivery is required for Erath observation mission now.
2. Methods
The COTS thermopile sensor is very popular for security
and hearth equipment ,then it can be used with low cost andshort delivery time .MESA use the 4pieses of multi-pixel
array of the COTS thermopile sensor .The points of MESA
developing is follows .
(1) Selection of sensor device

Previous

MESA

Fig2-2:Wave length distribution of infrared radiation(2) Methods for Earth edge detection

16 pixel location
Fig2-1:Caracterlistics of Rends
8 pixel location
Fig2-3:Pixel location

57

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SOMIRES2013-231th RISH

(3) Study structure to minimize components size .

4. Summary

Fig2-3:Over view of thermopile device

3. Results and Discussion
Fig4-1:Over view of Flight model
Earth area

Space area

Acknowledgements
This symposium is sponsored by Center for Environmental
Remote Sensing (CEReS), Chiba University and ResearchInstitute for Sustainable Humanosphere (RISH), Kyoto
University

Earth surface

Descrylevel

References
1)3M14 Development of COTS thermopile based Earth
Sensor for Small Satellite by JAXA

Descrylevel

Descrylevel
High resolution
Earth area

Space area

Earth surface

Low resolution
Fig3-1:Detection of Earth edge

58

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SOMIRES2013-231th RISH

Allometric modeling for biomass estimation in remote sensing
Ali Reza Sharifi and Jalal Amini
Department of Geomatics Engineering, University of Tehran
Tehran, IranEmail: jamini@ut.ac.ir
Abstract
This research develops an allometric model for estimation of biomass based on the height and DBH of trees in theforests of Iran. Without an accurate allometric model, we can’t estimate true biomass from SAR images. Afterextensive field investigations, 124 trees are selected from the 4 different dominant tree species for thedevelopment of an allometric model covering the wide range of DBH and height classes. Twelve commonly used
allometric models, three generic models and a proposed model are tested and the most suitable model is selectedbased on some of the commonly measured statistical parameters (coefficient of determination (R 2), RMSE, Mean
Error, Underestimated Error, and Overestimated Error). We show that the biomass estimation accuracy isimproved in a multilayer perceptron neural network (MLPNN) when the density of woods and the tree
measurements are used in combination compared to estimating the biomass by classic allometric models.
1.Introduction
The most suitable method for biomass estimation isremote sensing, as this technique is usually better than
traditional field-based methods when considering time,
costs, and feasibility (Brown et al, 1989, Calama et al,2008), although it is probably less accurate (Ketterings
et al, 2001, Zianis and Mencuccini 2004). However,the problem of the remote sensing-based biomass
estimation is that remotely sensed data do not directly
estimate the amount of biomass present in a forest(Mette et al, 2004). Field AGB is necessary forcomparing the result of remotely sensed methods inbiomass estimation. In general, field AGB is calculatedusing the allometric equations based on the measured
DBH and/or height or from the conversion of forest
stocking volume. Regression models have commonly
been used to relate field measurements to remotelysensed observations obtained via optical and radar
sensors (Brown et al, 1989, Mette et al, 2004). Thus,
field measurement of forest biomass remains necessary
for remote sensing of biomass estimation, and theaccuracy of remote sensing techniques largely depends
on the accuracy of ground data (Brown et al, 1989).
The method of field based biomass measurement
can be divided into two groups i.e. direct and indirect(Overman et al, 1994). The direct method involves thecomplete harvesting of sample plots and subsequent
extrapolation to an area unit (Araujo et al, 1999,
Charru et al, 2010). The indirect method aims toconstruct a functional relationship between tree
biomass and other tree dimensions, such as stem
diameter, height and wood density, by means ofregression analysis (Brown et al, 1989, Henry et al,
2010, Knapic, 2011). Since the direct method is verytime consuming, costly and completely destructive, andbiomass expansion factors (BEFs) are complex innature, field observations of biomass are normallybased on allometric models that approximate thebiomass of the tree component or the total biomass of
single trees according to easily measured variables,such as diameter at breast height (DBH) or height(Ketterings et al, 2001, Pilli et al, 2006).

2.Modeling
The relationship between the physical parameters(DHB or/and height) and the AGB of all harvested
sample trees needed to be established in order toestimate the AGB of non-harvested trees. Although
there are several empirical methods available, thisstudy established this relationship using allometricequations because an allometric model is a useful tool
which can approximate the AGB of single trees
according to easily measured variables, such as
diameter at breast height (DBH) or height (H)(Overman et al, 1994, Brown, 1997, Araujo et al, 1999,
Ketterings et al, 2001, Montagu et al, 2005, Pilli et al,2006(.
The most common allometric model in biomass
studies takes the form of the power function (Brown,
1997, Ketterings et al, 2001, Zianis and Mencuccini,2004, Pilli et al, 2006) as follows:
AGB = a. (DBH)b

(1)

Where AGB is the total above-ground biomass, DBH is
the diameter at breast height, a and b are the scalingcoefficient and scaling exponent, respectively. In mostcases, the variability of AGB is largely explained by thevariability of DBH. However, the values of a and b arereported to vary with species, stand age, site quality,
climate, and stocking of stands (Ketterings et al, 2001,
Zianis and Mencuccini, 2004), and the most common
problem with allometric equations as that the raw data
are non-linear and tend to be heteroscedastic.
As such, the equation 1 cannot satisfy the
relationship between AGB and the DBH. Hence, thestandard method for obtaining estimates for thecoefficients a and b ns by the least-squares regression
for D and M measured from destructively sampled
trees which represent the diameter range within thestands under investigation (Zianis and Mencuccini,2004, Pilli et al, 2006), and the form of the model will
be as follows (2):59

Copyright © 2013 by CEReSCEReS, Chiba University
RISH, Kyoto Universityln (AGB) = In (a) + b. In (DBH)

SOMIRES2013-231th RISH

(2)

Mette, T, Papathanassiou, K, Hajnsek, I, Pretzsch, H
and Biber, P, (2004), Applying a common allometricequation to convert forest height from Pol-InSAR data
to forest biomass, Geoscience and Remote Sensing
Symposium, 2004 IGARSS 2004 Proceedings 2004
IEEE International, 1, pp 269-272.
Overman, J P M, Watt, H J L, and Saldarriaga, J G,
(1994), Evaluation of Regression Models for AboveGround Biomass Determination an Amazon Rainforest,
Journal of Tropical Ecology, 10, pp 207-218.
Araujo, T M, Hnguchn, N, and Junior J Ade C, (1999),
Comparison of formulae for biomass content
determination in a tropical ram forest site in the state ofPara, Brazil Forest Ecology and Management, 117, pp
43-52.

This transformation is appropriate when thestandard deviation of AGB at and DBH increases inproportion to the value of DBH in many cases, logtransformation of real data results in homoscedasticityof the dependent variable AGB, a prerequisite forregression methods. However, even though the linear
relationship of equation 2 mathematically equivalent toequation 1, they are not identical in a statistical sense(Zianis and Mencuccini, 2004) and this transformation
introduces a systematic bias that is generally correctedusing a correction factor estimated from the standard
error, but it has become conventional practice inallometric studies (Niklas, 2006).
Different types of regression models andcombinations of parameters have been used including
ordinary least squares on log-transformed data
(Overman et al, 1994, Montagu et al, 2005, Pilli et al,
2006, Arevalo et al, 2007), weighted least-squares
regression on log-transformed variables (Arevalo et al,2007), and non-Iinear regression (Saint-Andre et al,
2004, Murali et al, 2005, Arevalo et al, 2007).
However, apparently there is no single optimal
regression model that can give a good calibration
function for the estimation of AGB because the valuesof coefficients are varied based on many factors(Ketterings et al, 2001 and Zianis and Mencuccini,2004). Considering this situation, this paper tested
different types of regression models for North of Iran
including linear and non-linear, but most emphasis wasplaced on the methods of Brown et al, (1989), Brown
et al, (1997) and Chave et al, (2005) as the work ofthese three researchers used in recently remote sensing
researches for estimation of biomass from SAR images(Amini and Sumantyo, 2009, Englhart et al, 2011,
Saatchi et al, 2011, Carreiras et al, 2012, Englhart et al,2012). Finally, proposed method was done with an
MLPNN. A multilayer neural network is made up ofsets of neurons assembled in a logical way andconstituting several layers.

Niklas, K J, (2006), A phyletic perspective on thealgometry of plant biomass partitioning patterns andfunctionally equivalent organ-categories, New Phytol,
171, pp 27-40.

Refernces
Brown, S, Gillespie, A J R, and Lugo, A E, (1989),
Biomass Estimation Methods for Tropical Forests with
Applications to Forest Inventory Data, Forest Science,
35, pp 881-902.
Calama, R., Barbeito, I., Pardos, M., del Río, M. andMontero, G. 2008. Adapting a model for even-aged
Pinus pinea L. stands to complex multi-aged structures.
For. Ecol. Manag., 256(6): 1390–1399.
Ketterings, Q M, Coe, R, van Noordwijk, M,
Ambagau, Y, and Palm, C A, (2001), Reducing
uncertainty in the use of allometric biomass equations
for predicting above-ground tree biomass an maxedsecondary forests, Forest Ecology and Management,
146, pp 199-209.
Zianis, D and Mencuccini, M, (2004), On simplifying
allometric analyses of forest biomass, Forest Ecology
and Management, 187, pp 311-332.

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RISH, Kyoto University

SOMIRES2013-231th RISH

Doppler Centroid Ambiguity Analysis for High Resolution SAR Imagery Sensors
Salar Gharibi , Jalal Amini
Department of Geomatics Engineering, University of Tehran
Tehran, IranE-mail: salar.gharibi@ut.ac.ir
Email: jamini@ut.ac.ir

Abstract
Attitude errors are significant for space borne SAR. The main effects of attitude errors are to decrease
the SNR and increase the ambiguities in the image. To maximize the SNR and minimize theambiguity ratio, it is desirable to centre the antenna beam on the target area being imaged. If there isan error in the knowledge of the antenna beam pointing direction (resulting from satellite attitude
errors or any other cause), the target area being imaged will be shifted with respect to the antenna
beam. This means that the image being formed is not centered about the centre of the antenna beam
[1,2]. To solve these problems in azimuth, it is common to determine where the antenna is

pointing after the fact using Doppler centroid techniques. In this paper, we show the
maximum available standard deviation of yaw and pitch angles of local coordinate system of
SAR for Unambiguous Doppler centroid frequency is a function of carrier frequency, lookangle, altitude of satellite, PRF and squint angle. We also show when the satellite using yaw
steering technique, errors in look angle and altitude do not affect Doppler centroid ambiguity
and maximum available errors for yaw and pitch angles of local coordinate system of SAR
sensor will be optimum.
Material and Method
Doppler centroid frequency for circular orbits[4].To satisfy the above condition (to avoid
incorrect able ambiguity) Standard deviationof Doppler centroid frequency withconfidential interval of %95 must be lesser
than half of the PRF; thus we have: Dop (%95) PRF
22) For eliminating earth rotation effect on
Doppler centroid frequency, satellite pointing
in Yaw Steering mode [4].
3) Squint angle (a) calculated by following
equation: a=a0+δa0-δa where a0 is squint angle
in yaw steering mode, δa0 is change of squint
angle which is arbitrary, δa is change of squint
angle caused by yaw and pitch angles of local
coordinate angle of SAR sensor.

(1)

Doppler centroid frequency is the function of
local attitude and altitude of SAR sensor.
Having considered that these parameters are
independent, standard deviation of Doppler
centroid frequency will be:4) We know that yaw and pitch angles of local
coordinate system of SAR sensor have only an
influence on the along-track parameter xp [5] :
(3)

(2)

Where γ is Look angle, R is slant range to
middle of swath width, Ψ and δ is yaw andpitch angle of local coordinate system of SAR
sensor, respectively. If δa is a function of Yaw
and Pitch angle of local coordinate system of
SAR; thus:

Where σγ is standard deviation of look angle,
σδa is standard deviation of change of squint
angle caused by yaw and pitch angle errors of
local coordinate of SAR sensor and σH isstandard deviation of satellite altitude. The
following conditions are considered in our
simulation:(4)1) Satellite is sun synchronize

61

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RISH, Kyoto University

SOMIRES2013-231th RISH

If: tan (δa) ≈ δa; tan (Ψ) ≈ Ψ; tan (δ) ≈ δ; thus,
we have:

References[1] D. Bickel, B. Brock, C. Allen, and S. N.
Laboratories, Spaceborne SAR Study: LDRD
92 Final Report: Sandia National Laboratories,
1993.
[2] F. K. Li, D. N. Held, J. C. Curlander, and C.
Wu, "Doppler parameter estimation forspaceborne
synthetic-apertureradars,"Geoscience and Remote Sensing, IEEE
Transactions on, pp. 47-56, 1985.
[3] B. Barber, "Theory of digital imaging fromorbital synthetic-aperture radar," International
Journal of Remote Sensing, vol. 6, pp. 10091057, 1985.
[4] R. Raney, "Doppler properties of radars incircular orbits," International Journal of
Remote Sensing, vol. 7, pp. 1153-1162, 1986.
[5] A. Hein, Processing of SAR data: fundamentals,
signal processing, interferometry: Springer
Verlag, 2004.

(5)
(6)

Having considered conditions mentioned
above, we illustrate graphs (Fig. 1) of
maximum available standard deviation of yaw
and pitch angles of local coordinate system of
SAR for Unambiguous Doppler centroid
frequency as a function of carrier frequency,
look angle, altitude of satellite, PRF and squint
angle. We also conclude that when the satellite
using yaw steering technique, errors in lookangle and altitude do not affect Doppler
centroid ambiguity and maximum available
errors for yaw and pitch angles of local
coordinate system of SAR sensor will be
optimum.

Fig 1. Effects of Pith and Yaw angles on the
Unambiguous Doppler centroid frequency

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