Development of RF Front-End Chip for
Wireless Communications

Department of Electrical and Electronic Engineering
Graduate School of Information Science and Electrical Engineering
Kyushu University

H. Kanaya, R. K. Pokharel and K. Yoshida
http://yossvr0.ed.kyushu-u.ac.jp
1

Driving Force: Wireless Technologies
Wireless LAN、Cell Phone、Cordless Telephone、IC Card, ITS, DSRC
Camera
車線監視カメラ

路側表示器（出口）Antenna

路側無線装置（アンテナ）

通信開始 装置

車両検知器
発進制御機

Electronic-Toll Collection System.

Wireless LAN

Ｓａｔｅｌｌｉｔｅ Ｃｏｍｍｕｎｉｃａｔｉｏｎｓ

Cell Phone Cordless Phone2

Silicon Sea Belt Fukuoka Project＊Center of Semiconductor design.
Silicon Sea Belt Fukuoka Project＊Semiconductor Industry: Driving force for the ＊World production: 50%
South consumption
Korea
growth.
＊Largeregion＊ Fukuoka is addressing to establish a center ofExcellence for SoC design in this area.
KyushuShanghai＊Conventional Semiconductor Industry(Memory, Processor)-System LSI
Okinawa＊System LSI is expected to generate the higher
added value to the cluster of related industry.

Silicon Sea Belt Fukuoka Project
TaiwanHong Kong

Malaysia

zKyushu as a Silicon Island: A
global base for System LSI design.
zInstitute of System LSI DesignIndustry, Fukuoka

Singapore3Fukuoka Soft Research Park
Momochi Hama District
Fukuoka Tower

SRP Center Building

Yahoo Dome
ヤフードームInstitute of System LSI Design Industry, Fukuoka（Kyushu University:Entrepreneur Promotion Center）
Established on 2004

World Class Companies of Japan and Korea:Toshiba, Sony etc
4System LSI Research and Development
Innovative Ideas:
DesignEDA Tools(CAD design tools)
By VDEC

Foundry(TSMC, Hitachi)

0.18um CMOS
VDEC：VLSI Design andEducation Center(University of Tokyo)

Patents

Prototype model

Testing(Underground Floor)

Research Papers(Journals andInternationalConferences)
5Prof. Yoshida’s Lab Introduction

Receiving RF CktReceiving IF Ckt
Antennas

Tr. Amp.

Digital Ckt.

Intersil 2.4GHz PCMCIA Card (PRISM 2.5)

Key Words of Our Research

Miniaturization & Low Power⇒ ① SoC (System on Chip)⇒ ② Antenna

6

Block diagram of CMOS-LSI for WirelessCommunications
Mixer

Receiving partVGA

② Antenna

LPF

A/D

VCO, PLL

ＬＮＡ

digital

PLL

proc.

ＰＡ

PHY

Mixer

Buff

LPF

D/A

Transmitting part

Research contents

With Collaboration

Direct Conversion Receiver Type
①1-Chip:SoC Implementation (System on Chip)
7

① Proposal of New Design Methodologies for RF Parts
Lump Elements
Spiral Inductors

MIM Capacitors

Spice ModelsSize is about 40% and the shape
can be adjusted to exploit thevacant space in the chip.

Transmission line
MatchingCircuits

λ/4 Line ReactanceCompensationckt.

Impedance reversal Ckt.
（Inverter）

Meander line

Freedom of Design8

Matching by Lumped Elements

S (1,1)S (1,1)S (1,1)High Impedance（Say:100-j1000)Ohm is matched to 50-Ohm

Insertion of L
fre q (5.000GHz to 5.000GHz)

Insertion of C
fre q (2.450GHz to 2.450GHz)

fre q (2.450GHz to 2.450GHz)CG

Very small CCG CL

High L is necessary.

G CL

Insertion of Series C（0.09pF）
9fre q (5.000GHz to 5.000GHz)

S (1,1)S (1,1)S (1,1)

Theory of Matching Circuit

Impedance
Reversal
fre q (5.000GHz to 5.000GHz)

AGC
A’

Impedance transformation
Due to K-inverters

fre q (5 .0 0 0 G Hz to 5 .0 0 0 G Hz)

ACompensation
ckt

Z1, θ−C GC

λ/4Δl-LK-L
L

A’

Compensation ckt

Z1, θ−C G

λ/4Δl

C

Eq. Ckt of Inverter¾Presented at IEEE RFIC2006.

10

Prototype Design [I]
TSMC 0.25μm CMOS (1P5M)
Chip size=5mm x 5mmMixer(Down)BG

LNA
w/ CPW

LNA
w/ L

L

L
Mixer
(Up)
L

L

DAC
L

L

L
LNA

VGA

L
Mixer+LNA

CPWCPWL
PLL•••••••••

LNA; Cascade, w/ CPW, w/L
Mixer; Up, Down
Down Mx +LNA
PLL
BG
VGA
DAC
Inductor TEG
CPW TEG

11Prototype Design [II]TSMC 0.18μm CMOS (1P6M)
Chip size=5mm x 5mm

VCO

5mm

ADC

Mixer

VCO

zUWB-LNA, mixer,ADC, DAC
zTest chips.
For MIMO-MESH ProjectMixer

LNA DAC zMixer, VCO, 1-bit ADC

5mm
12TEG Chip Photo

PKG
Substrate

Close-up Figure
Cal. patterns

13

Lab Facilities of Testing50Ω cable

Cascade Microtech

LSI chipProbe
Air Coplanar Probe

Spiral inductor
14

Results [1]•Power Amp. (IEEE .11b)•LNA (UWB)•VCO & DCO (IEEE .11a)•LNA + Mixer (IEEE .11b)•Ring Oscillator
TSMC:
0.35um Bi-CMOS, 0.25um CMOS &0.18um CMOS
15

Power Amp.
1.05 [mm]Outputmatch

15

10.495 [dB]

S11S2110

2.38 [mm]S parameter [dB]

Input Match

TSMC0.35μm Bi-CMOS process

S2250-5-10-15-20-25
12345Freq [GHz]67168Ultra wideband (UWB) Low noise Amp. (LNA)
1mm

RF probe pads

RF probe pads

0.7mm

Chip photo of the designed UWB LNA in 0.18um CMOS.
17

Gain, S[21] (dB)

Measurement results≅

BW 7GHz

Reference

S21

NF(dB)

S11 (dB)

Freq. (GHz)IIP3 (dBm)

JSSC[1]

9.7~7

4.5~5.1<-113.1~10.6-6.2

0.18µmCMOS

JSSC [2]13

3.3 (max 6.5)<-72~10-70.18µm
BiCMOS

Ref. [3]9.55 (max 5.6)<-103-11-130.18µm
CMOSThis work(Post-layout)16.5(flat)<3.7(flat)<-93.1~10.6-> Presented at IEEJ Analog VLSI symposium, Aug, 2008.

-8

Technology

0.18µmCMOS
18

VCO (Voltage controlled Osc.) with TML

6.4

Frequency (GHz)

6.2

TML VCO

65.8
5.6
5.4
5.2

LC VCO

54.8

00.4
0.8
1.2
DC Control Voltage (V)1.6

TML VCO= -112dBc/Hz @1MHz
LC VCO= -110dBc/Hz @1MHz100μm

19

TSMC0.18μm CMOS process

LC-DCO (Digitally controlled OSC)TML Capacitor

４C ２C CC ２C ４C

Ｖ１

5.1

Ｖ２６４C ３２C １６C ８C ８C１６C ３２C ６４C

5Ｖ４Ｖ５Cvar

Cvar

Ｖ６CvarCvar

Ｖ７CvarCvar

Ｖ８CvarCvar

Ｖ９CvarCvar

Ｖ１０Cvar

Cvar

Cvar

Cvar

On-OffFrequency (GHz)

Ｖ３

4.9
4.8
4.7
4.6
4.50200

400
600
800
control word (10bit)

1000

LC VCO= -119dBc/Hz @1MHz
20

TSMC0.18μm CMOS process

LNA + Mixer (Down converter)
Down conversion mixer（50Ω）

CPW
Matching
circuit

LNA

CPW
Matching
circuitMatching circuit

VCO

Layout (LNA + Mixer)
LOSizeLumped element TML

Chip Size
3.3mm×2.0mm

LO
480μm×250μm

RF_IN

600μm×300μm21（約14.0nH @2.45GHz ）LNA + Mixer (Down converter)
K-inverters andCPW lines

Input Impedance

80Real parts

Input Impedance [ Ohm]

60

Simulation
Measured40200-20
Imaginary parts-40-60
-80

Mixer

LNA

Input
matchingcircuit

1234

Frequency [ GHz ]Matching circuit between
LNA and mixer

Output by Oscilloscope(Base band freq.=10MHz)

22

Ring-Oscillator
Demand of Wideband Systems
WLAN(.11a,.11b), WCDMA, GPS, PHS, GSM, IMT2000 …

●Reconfigureable RF circuit.
●Multi-standard systems in one terminal.
RFIDUWBGPSFMDTVTel.
MobileTerminal

WLAN
BluetoothTV
23

Proposed Quadrature Ring Oscillator
Chip photo
TSMC 0.18um CMOS Process
Q180
I1

Q270

I2

I3

Q90

I4

Q180

Q0
M2 Vdd

M1
Q270
M3nMOSpMOS
M4
Q90
W180

Vss

Additional transitionassistance pairSize:0.30 mm2 with bonding pads.
Size: 0.01 mm2 without bonding pads.
24

Measurement results
Time-Domain

Tuning Range

zTuning Sensitivity = 2.9 MHz/mVzTuning range = 1.7 GHz ～5.5 GHz
zFOM= -162.2 dBc/Hz
Figure of Merit:⎛ Fosc ⎞⎟ + PN + 10 log ⎛⎜ Pdiss ⎞⎟FOM = − 20 log ⎜⎜ Foff ⎟⎝ 0 .001 ⎠⎝⎠25

Wireless System LSI
Digital techniques: a New Concept in RF circuitdesign:Digitally-assisted RF/Analog
DSP

RF Front end
ADC, DAC

LNA, Mixer, PA,
Baseband processing unitPLL, VCO

Key word: RFIC (Digitally-assistedRF/Analog)

26

② Development of Miniaturized Integrated Antennas
Intersil 2.4GHz PCMCIA Card (PRISM 2.5)5cm

Antenna

LSI
27
Small size, thinner and one-sided directional antennas are necessary!

Antenna Applications•One-sided directional antenna
300MHz, UHF, 2.4GHz (.11b), MIMO (.11a), UWB•Electrically small antenna with matching circuit
UHF, 2.4GHz, 5GHz
•Dual band antenna
PDC + 3G (800MHz + 2GHz)

28

Simulated field pattern and radiation pattern of the onesided directional antenna
Z

HFSS@2.4GHz

Forward θY

LfrontForwardZ

φTop layer

θφ =90°X

Back
Bottom layer

φ =0°
Back
E- field
Near field

29

Advantages of Proposed Theory:Gain can berealizable at thinner Substrate
Ftt

B
Thickness of thesubstratet [mm]

1.6

0.8

0.4

One-sided slot

Gain[dBi]

1.177

0.81-1.516○Patch antennaGain[dBi]

1.254-1.057-4.145

×….advantage for multiplayer MMIC circuit.

By 3D-EM Simulation30

Electrically small antenna (ESA)

An antenna that dimension is much smaller than quarter wavelength…

⇒Antenna length < λ/4
Small Radiation Resistance
Narrow bandwidth
Sensitive to the conductor resistance

Impedance Matching
Design of Bandwidth

One-Sided
Directional
Antenna

Proposed
Antenna

integrates
31

Antenna Fabrication and Measurement System
PCB Makers (MITS Co.)

PCB

High-frequency
Milling Cutter
VNA

Vector Network
Analyzer:HP8722C
MMCX-SMA
Connector

32

AntennaPhotograph of the ESAs
Size comparison of the antennas

standard slot dipole antenna(size:74.0mm×24.0mm,gain:3.92dBi)

ESA2ESA1

MMCX Connector(50Ω)(unit : mm)
Enlargement of the ESAs

J-inverter

G SG

J-inverter

33

Experimental results of the one-sided
directional ESA with CPW matching circuit
Photographs of the antenna019.3mm

Measured-10
Return Loss [dB]

J-Inverter(Inter digital gap)

Band width-20-30-40

EM Sim.
-50

22.2

2.4
2.6
Frequency [GHz]2.8334

Experimental results of the one-sideddirectional ESA with CPW matching circuit
RF-ID Card

@2.45GHz (IMS band)

PC
Antenna

Reader-Writer

35

Setup of Radiation Pattern Measurement
In the anechoic chamber
Test antenna

ReceivingTransmitting

Turn table
36

Comparison of the sizes of the one-sided
directional antenna

Patch antenna #1
75mm□×t5mm

Patch antenna #2
45mm□×t1.6mm

ESA
39×19×t0.8mm
37Measured communication distance and antenna
size of the patch antenna and ESA

10Friis' Transmission Formula

5FrontBack300250

104200150
3310100

81%
reduced !

50010

Patch #1

Patch #2

RXTXAntenna size [mm ]Communication distance (mm)

350

dGr

Gt

Power received by the RX antenna

2λ ⎞Wr = ⎛⎜⎟ GtGrWt
d4π⎠⎝2ESA38UWB High Band one-sided directional antenna
0yExp.

Return Loss [dB]-5-10-15-20-25

Sim.

-30
-35
6.5

77.5

88.5
99.5
Frequency [GHz]10 10.5

Three resonance—broad bandθ
φ =0°

7.25GHzφ =90°

8.25GHz

9.25GHz 39

UHF visiting-card size one-sided directional antenna
0y-5|S11| (dB)

-10-15-20-25-30
800

850

900950Frequency (MHz)1000

75ｘ－ｚ面ｙ－ｚ面

Input Impedance (Ω)(Sim.)

Re [Zin]
Im [Zin]50250-25

F/B：8dB

Human body or metal surface like auto mobile.

-50
800

40850900950
Frequency (MHz)1000

New national project (PICO, MIMO) MESH Network
One-sided directional
planar antennas

MIMO-MESH, Pico-MESH
Conventional MESH Device

MESH Point

More than 10kg
Limitation= 2~3 hubs

Large ★ＭＩＭＯ－ＭＥＳＨ
・Ｂ社
・Ｔ社

・Ｓ社

Fix

★Ｐｉｃｏ－ＭＥＳＨ
Portability

Small・SensornodeRF front end + IP Core41

MESH Antenna @5GHz
Conventional
H:15.7mm×D:1.1mm5dBiZZXYYX

New Antenna
22mm×28mm
5dBi （One-sideddirectional）

F/B：10 dB

42

Measurement system of communication distance
Node

Node Photo
Ath0 ： 192.168.0.＊/24

Ath0 ： 192.168.0.1

Ath0 ： 192.168.0.2

Node B

Node A
Ath1 ： 192.168.1.1

Ath1 ： 192.168.1.2
Ath1 ： 192.168.1.＊/24※Speed：36Mbps, Frequency：52ch(5.26GHz), Amp. output：17dBm(50mW)

Field:
Building

W2,8F

Node B

100m

Node A42m
点線上でノードBの位置を変化←Scan→43

Measured communication distance
25Throughput [Mbps]
スループット[Mbps]

201510Our antenna:
put put
金谷研アンテナ
Our antenna:
get get金谷研アンテナ
Conventional:
黒アンテナputputConventional:
黒アンテナgetget

50050

100

150

200250

ノード間の距離[m]Nodedistance [m]communication distance ＞ 200m

44

MIMO-MESH Point
Back bone network
Wire
Wireless Line

HostNodePCInternetphone

Wireless LineA small antenna is necessary !!

Case

Antenna plate

Ant・Small size
・One sided directional
・Wide band
（4.9GHz～5.7GHz)
45

Mounted 6 platesAntenna plate

A5A6A7A8A1A2A3A45.8cm

9.4cm
46

ConclusionzRF COMOS Front-end (RFIC)zPlaner type small antenna
Applications:3G, .11a,b &g,MIMO,PICO and UWBDetail:RFIC Japan
Thank you for your Attention!

47