# Presentation: 091393

## Advanced Technology Microwave Sounder (ATMS)

***Jim Shiue***
***NASA Goddard Space Flight Center, Laboratory for Hydrospheric Processes***

***For NPP Science Team Meeting***
***November 4, 2003***

**	****	**** ****Contents:**
**Background & Heritage**
**New features of ATMS**
**Channel freq. & other parameters**
**Block diagram/Hardware design**
**Scanner profile**

## ATMS

**   ***** **_**Heritages**_**:**
**	****- From AMSU-A & AMSU-B, HSB, NOAA-15, -16, -17, AQUA & METOP (Eumetsat)**
** **
**   ***** **_**Other features**_**:**
**	****- Uses advanced technologies (e.g. LNA, MMIC) to reduce instrument noise, mass, power & volume**
**	****- AMSU: P=200 W,   M=160 kg,****	**** V. ~ 1 m****3**
**	****- ATMS: P= 93*/(110)W, M= 76*/(85) kg, **
**	****  ****V. ~ 0.2 m****3**
**	***** = Predicted, as of 9/03;  (xx)= Allocated**
**	**

## ATMS 

_**Other features continued**_**:****	**
**	****- ATMS V<70(vel.)x60(nadir)x40 cm****3**
**	****- ATMS has 3 more channels than AMSU **
**	****- better radiometric resolution (NEDT)**
**	****- better sampling and spatial resolution ****	****(in temperature sounding channels)**
**	***** NASA develops the EDU & PFM; IPO takes over for FM1- FM4**

## ATMS

**	**_**Other features continued**_**:**
**Temperature sounding channels have 2.2****o**** beams; Nyquist-sampled in both along-scan & down-track directions**
**Total-power radiometer; cross-track scan (integrate-while-slew); filters setting bandwidths**
**Hot-&-cold, 2-point on-board calibration once every scan period (8/3 second)**

## ATMS Channel Center Locations

**ATMS Channel Center Locations**

**Ch.3-15**

**Ch.1**

**2**

**22**

**21**

**Ch.19**

**Ch.18**

## ATMS Channel Parameters

**ATMS Channel Parameters**

## ATMS Channel Parameters

**ATMS Channel Parameters**
**(continued)**

## Functional Block Diagram

**1 Hz**
**Time **
**of Day**
**Pulse**

**Electronics**

**CCA**

**Dual**

**power amp**

**Power**

**supply**

**57 **

**GHz**

**PLLO**

**Scan drive electronics**

**Receiver Subsystem**

**Antenna Subsystem**

**Digital**

**signal**

**processor**

**Filters**

**Video**

**Digitizer**

**Electronics Subsystem**

**Ch.**

**1-2**

**Ch.**

**3-15**

**Ch. 16**

**Ch**
**16-22**

**Ch**
**1-11**

**Redundant**
**Spacecraft interfaces**

**HKPG**

**CCA**

**Passive**

**analog**

**telemetry**

**1553B**

**RFE**

**MXR**

**Filters**

**MXR**

**Ch. 17-22**

**Scan Drive**
**Subsystem**

**SAW**

**Filters**

**CH**
**12-15**

**Filter**

**Filter**

**LNR**

**LNR**

**DPLX**

**Ch1**

**Ch2**

**Hot****Targets**

**Video**

**DPLX**

**Video**

**Video**

**Ch. 18-22**

**Ch. 17**

**Discrete**

**pulse**

**commands**

**Operational**
**Power**

**Heater**
**Power**

**PRT**

**PRT**
**Data**

**1/8 Hz**
**Scan Sync**
**Pulse**

**Notes:**
Style conventions:
Each ‘unit’ is a white rectangular box, with black borders and black text
Redundancy indicated either explicitly, with separate boxes, or with the corner symbol as shown
Partition into major assemblies with black dashed-line borders, filled with a pastel background color.  

For subsystem block diagrams, an “assembly” is a package that is separately integrated at the system level, e.g. SPA, V-shelf. “Units” are the next lower level, e.g. Video Digitizer, CSO.

## ATMS Instrument Design

- 0800-3138

**Parabolic**
**reflectors **

**Ch. 16-22**

**Optical bench**

**Scan drive**

**Feedhorn**

**Ch. 1-15**

**IF digital**
**filter**
**assembly**

**Alignment cube**

**Power distribution**
**assembly **

**Signal processor**
**assembly **

**Scan drive**
**electronics**

**Nadir (z)**

**Antisun (y)**

**Lower**
**assembly**

**Upper**
**assembly**

**Velocity (x)**

## S/C velocity: out of plane of paper 

- 0600-3335

**18.018 ms per beam**
**96 beams 1.11° on-center**
**4 selectable cold cal positions**

**Nadir**

**POS**
**# 1**

**POS**
**# 96**

**Cold**
**(4)**

**Hot**

**Sync pulse**

_**Scan Pattern**_

- C

- A

- B

**(4)**

**Cosmic**
**background**

**Sun**

**(48)**

**(48)**

**Earth scene sector**

**S/C velocity: out of plane of paper**

**at location B**

**(Hot cal.)**

**#1**

**     ****#96**

## Scanning Characteristics

- 17.6 km
- Scan spacing

-  Swath = 2503 km

- 16.0 km

- 65.7 km

- Subsatellite track direction

-  Sample interval

**(824 Km orbit, NPP)**

- 105.45°

**Contiguous; 1.1° cells**
**Nyquist ; for 2.2° cells**

**IFOV #96**

**IFOV #1**

_**Sampling:**_

## ATMS Channel Parameters (cont.)