# Presentation: 404805

## Mars Atmosphere Temperature and Humidity Sounder (MATHS)

**Description:**
- Develop sub-millimeter wave (557 GHz) up-looking radiometer prototype.
- Provide Martian atmospheric observations addressing critical questions in our understanding of Martian climate and volatiles
- Provide essential environmental data for design of future Mars Exploration Program (MEP) landers, rovers, and aerial platforms.

**FY04-FY06 Critical Milestones:**
**FY04****	****System Design Complete ****	**** 5/1/04**
**	****Sub-mm Receiver Complete****	****9/30/04**
**FY05****	****IF Processor Complete****	**** 4/1/05**
**	****Cal & Antenna Complete****	**** 5/1/05**
**	****Mech. & Thermal Complete****	**** 5/1/05**
**	****Detector & Data Sys. Complete****	**** 8/1/05**
**FY06****	****Instrument I&T Complete****	**** 3/1/06**
**	****Environmental Test Complete****	**** 6/1/06**
**	****Final Report Complete****	****9/30/06**

**Funding Profile ($K):**

**Technology Tasks:**
- 	1.0 Instrument Design 	L. Riley/386
- 	2.0 Science Design 		M. Janssen/326
- 	3.0 Receiver Development 	E. Schlecht/386
- 	4.0 Backend Development
- 		4.1 IF			L. Riley/386
- 		4.2 Electronics		R. Denning/386
- 	5.0 Antenna & Mechanical
- 		5.1 Antenna		L. Riley/386
- 		5.2 Mechanical		TBD/35x
- 	6.0 Integration & Validation	TBD/386

- 200 mm

- Dimensions:
- 200 x 100 x 75 mm

- Radome

## FY’04 Milestones

- Blue = Original schedule
- Red = Actual and revised schedule

## Technical Accomplishments

**Major technical accomplishments for this technology area during the last quarter:**
- Preliminary science requirements developed
- Modifications to instrument design as proposed
- Completed optimization of the instrument system design
- Optimized frequency down conversion plan
- Defined critical RF component requirements
- Completed design of antenna optics
- Defined antenna optical prescription
- Defined antenna illumination and patterns
- Completed assembly and test of prototype 557 GHz receiver
- Collected and inventoried spare MIRO receiver parts
- Plated receiver bodies
- Assembled and tested receiver
- Began design of advanced MOnolithic MEmbrane-Diode (MOMED) 557 GHz receiver
- Began design of MATHS electronics

## Significant Events

- Temperature is sounded in the 576 GHz CO line
- 	0 – 6 km altitude range
- 	2- 5 K accuracy
- 	100 m resolution at surface
- 	5-min time scale (change from hourly)

- Water is sounded in the 557 GHz H2O line
- 0 – 6 km altitude range
- 30% relative K accuracy
- 100 m resolution at surface
- 5-min time scale (change from hourly)

**MATHS profiles temperature and humidity in the PBL.  Proposed requirements were reexamined in light of MER results.**

**Reexamination led to modifications of instrument as proposed**
- Discrete elevation stepping at fewer points to speed up data collection
- Consecutive rather than concurrent sampling of the two lines
- No time saved by concurrent sampling
- Simplifies instrument (only one channel needed instead of two)
**Modeling of retrieval procedure in progress**
- Atmospheric dynamics model used to generate sample cases
- Forward calculation developed
- Retrieval algorithm outlined
- Will be used to develop detailed requirements for instrument

## Significant Events

**Significant Events**

**Completed System Design Trade-off Study**
- Developed optimized system architecture
- Optimized spectral design
- Analyzed LO spectral performance to minimize line interference
- Considered 12CO, 13CO, H216O, H217O and H218O lines.
- Developed simple design to minimize mass and power consumption
- Is key to design to meet science goals and performance requirements
- System design approach:
- Spectral analysis of CO and H2O lines by stepping frequency of first local oscillator
- Double down conversion with fixed second local oscillator
- Switch to provide alternate measurements of CO and H2O lines

## Significant Events

**Antenna design completed**
- Designed antenna optical prescription
- Antenna design was carried out to meet 1.5 degree beam width requirement
- A electromagnetic field analysis program was use for simulations
- Antenna design is critical to meeting MATHS atmospheric measurement requirements
- Antenna characteristics:
- Antenna is 31 mm aperture 90 degree offset parabolic reflector fed by a Pickett-Potter horn
- -30 dB edge illumination gives less than –35 dB first sidelobe levels

## Significant Events

**Completed assembly and test of brassboard 557 GHz receiver**
- Completed brassboard receiver
- Collected and inventoried MIRO receiver parts
- 557 GHz mixer body and diodes
- Frequency tripler
- 140 GHz Gunn oscillator
- Subharmonic mixer
- Got agreement from MIRO Project for use of parts
- Assembled and tested mixer
- Integrated and tested receiver
- Receiver is the most challenging component of the instrument
- Test results indicate adequate performance for breadboard instrument
- Less than  6,000 K double sideband noise temperature at relevant frequencies
- More than 2.3 GHz input frequency tuning range

- Input Feedhorn

- Mixer

- 140 GHz Gunn Oscillator

- Frequency Doubler

- Subharmonic Mixer

- IF Output

**System Noise Temperature ********6,000K**

**LO Tuning Range ********338 MHz**

## Plans for Next Quarter

**Procure intermediate frequency components**
**Complete assembly of first iteration of MOMED mixer**
**Complete assembly and begin test of digital control and bias electronics**
**Begin mechanical design of instrument**
**Begin antenna scan mechanism design**
**Begin fabrication of antenna reflector**
**Procure calibration targets**

## Financial Status: Obligations & Cost

## Financial Summary

**Development effort is on schedule**
**Obligation of funds is at a rate lower than planned**
- The general plan has been to focus the funding during the first year on development of the receiver.
- Receiver development using MIRO residual parts started late but took less time and was less expensive that originally predicted.
- With completion of the receiver, work is now beginning to focus on other aspects of the instrument including intermediate frequency components, electronics and mechanical design.
- It anticipated that an under run will occur this FY but that the funding will be used for more through test and analysis during the latter two years of the project.

## Action Items/Issues/Concerns

**No previous review has taken place on this task.**
**Re-plan will be carried out since receiver delivery is ahead of schedule.**
- Intermediate frequency and electronics development will be accelerated.
- Mechanical development will be accelerated.
- More thorough testing will be carried out in the validation phase including more measurements of simulated Mars atmosphere