1. Microwave, Sub-mm, and THz Technology for payloads and space (sub)systems
Radiometer Physics GmbH (RPG), Germany
Harald Czekala RPG
Thomas Rose RPG
AchimWalber RPG Hugh Gibson RPG
Bertrand Thomas RPG
Michael Brandt RPG
Oleg Cojocari ACST
Byron Alderman STFC RAL

2. RPG Company Profile Microwave, sub-mm, THz
Turn-key radiometers, space technology components, design, scientific expertise
■ 4 decades experience
■ 40 employees
■ Radiometers (space)
■ Frontends/Receivers
■ Lab equipment / VNA
■ Components up to THz
■ Design+Manufacturing
RPG Microwave Technology SAC,

3. RPG Space Heritage
MLS/UARS Microwave Limb Sounder (JPL/USA, 1991) (RPG founders working with JPL on Gunn oscillators/multipliers)
MHS/FY-3 Microwave Humidity Sounder (CNSA / China, 2008) 150 and 183 GHz Receiver front ends for MHS
ODIN (SSC, 2001 until today) 8 Gunn Local Oscilaltors plus fudamental mixers
Herschel / HIFI space telescope (ESTEC, 2009) Local Oscillators (480 to 1200 GHz), IF up-converters
SMILES (JAXA, 2008 installed on ISS) PLL Gunn LO chain at 360 GHz
RPG Microwave Technology SAC,

4. RPG Space Heritage (2)
SAPHIR+MADRAS / MEGHA-TROPIQUES microwave humidity sounder CNES/ISRO
SAPHIR (183 GHz sounder): specially stabilized Gunn resonator (plus contrib. to LO and RF hardware)
MADRAS (18.7, 23.8, 36.5, 89, 157 GHz Imager) Gunn LO, DC conditioning, RF networks (M4/M5, 89/157), OMT
Components…
RPG Microwave Technology SAC,

5. Space heritage components
Waveguide Components passive
Corrugated feed horns
Attenuator
Coupler
RF loads, absorbers
RF power splitter
Isolator (Y-junction circulator/isolator, Faraday isolator)
Waveguide twists
Orthomode Transducers (OMT)
Optical networks (feedclusters, FSS)
Power supply
RF components
(whisker contacted multipliers)
(Gunn oscillators, with PLL / cavity)
Planar Multipliers
Subharmonic mixers
Fundamental mixers
MMIC driver amplifiers
MMIC low noise amps (LNA)
Noise injection (calibration!)
Rapid Dicke switching (4-point cal.)
PA/QA to delivered hardware
RPG Microwave Technology SAC,

6. Current involvements
ESA TRP (Technology Research Programme) activities
ESTEC "Integrated Schottky Structures" (664 GHz Front End)  tripler-mixer FE with integrated circuit design
ESTEC "Sub-Millimetre Wave Receiver Front-end" (664 GHz Frontend)  doubler-doubler-mixer with discrete Schottky diodes
EU/FP7 "Millimeter-Wave Integrated Diode & Amplifier sources"  over 400 mW (later: 1000) 100 GHz
Qual/Eval activities aiming at TRL-5 expected soon
ESA-ESTEC/EUMETSAT METOP Second Generation („Polar Orbiter“)
"RPG Sat-B CPI coordination and interface definition support" (OHB)
MWI/ICI Receiver Performance & Test Requirements definition (TAS-I)
ESA "Cloud and Precipitation Airborne Radiometer" (118 & 664 GHz FE)
Proposal ESTEC "243 GHz Direct Detection Radiometers"
RPG Microwave Technology SAC,

7. Quality Control, tests, procedure, … (PA/QA)
RPG offers PA/QA compliant to highest ESA and NASA standards
RPG has demonstrated these capabilities
RPG advises customers on suitable (tailored) approaches
RPG Microwave Technology SAC,

8. Space Products (II) Space qualified front ends (China, FY-3):
183 GHz (4 channels) water vapour sounder
RPG Microwave Technology SAC,

9. Space Products (III) Space qualified front ends (China, FY-3):
90 GHz dual polarized receiver OMT + LNA + (either Direct Detection or Heterodyne)
150 GHz dual polarized receiver: OMT + SHM
RPG Microwave Technology SAC,

10. Examples: Frontends and sub-systems for Space
FIRST/HIFI
MADRAS
Space qualified local oscillators (Herschel / ESA):
8 local oscillator chains from 480 GHz to 1100 GHz
Other space projects:
EOS (NASA), ODIN (SSA), FIRST/HIFI,
MARFEQ, SAPHIR (CNES), MLS (NASA), FY-3 (China), …
RPG Microwave Technology SAC,

11. Outline Direct detection (MMIC) for frequencies up to 120 GHz
Auto-calibration receivers up to 200 GHz (noise-injection / Dicke sw.)
Improvements in mixer and multiplier designs through close cooperation with Schottky diode suppliers
Schottky technology from ACST (Germany)
Schottky technology from RAL (UK)
Subharmonic mixers at 424 GHz and 664 GHz
InGaAS mixers with reduction of LO power by 10 dB
RPG Microwave Technology SAC,

12. Direct Detection
Direct detection systems up to 110 GHz (since 8 years now…)
LNA mostly based on MMIC supply from IAF Freiburg, Germany
At 118 / 150 / 183 GHz and above, sub-harmonic mixers still have better performance (at least with high-quality sub-harmonic mixers)
Waveguide filters with high stability and narrow bandwidth (0.25 %)
Tsys (with horn, noise-inject., isolator)
20 – 30 GHz
280 K (NF: 2.9)
50 – 60 GHz
550 K (NF: 4.6)
90 GHz
700 K (NF: 5.3)
55 dB Pre-Amplifier
Splitter and
Filter Section
Boosters and
Detectors
Video Amps,
MUX, 16 Bit ADC
Noise Injection
Coupler
GHz
7 Channel
Filterbank Receiver
170 mm
Corrugated
Feedhorn
RPG Microwave Technology SAC,

13. Direct Detection Receivers
Compared to heterodyne systems:
Improved noise figure
Decreased long term stability (larger 1/f noise with InP MMICs)
Much better RFI protection
Compact (integrated) design
No planar filters, all waveguide
Low loss Ortho-Mode Transducer
Tsys < 600 K (NF: 4.9)
90 GHz dual-pol (FM)
RPG Microwave Technology SAC,

14. Direct Detection: MMIC mounting
Mounting of all amplifier types
Experience in micromachining
Bonding and soldering to space standards
RPG Microwave Technology SAC,

15. Auto-calibration receivers: Noise injection, Dicke Switching
Fast calibration with noise diodes and ambient load (gain and Tsys are calibrated)
Ambient load / Dicke switch: Isolators driven by switched magnetic field
Noise diodes: mounted directly in a waveguide coupling section
Applied to direct detection as well as heterodyne receivers
Usignal
Uambient+noise
Uambient
Repetition: 5 Hz
Duty cycle: 45 % (due to 10 ms switch time)
DetectorVoltage
Time / s
0.10
0.20
0.15
0.05
RPG Microwave Technology SAC,

16. Auto-Calibration Receivers (II)
Noise injection calibration up to 200 GHz
7.000 K signal at 183 GHz with stable noise diode (15 dB ENR)
Magnetically switched isolators: Dicke switching up to 150 GHz with low insertion loss (≤1.0 dB)
Fast switching with low currents (small thermal effects, 100 mA, 0.5 V)
ESA-ATPROP 15 / 90 GHz
Allan Variance Stability: s
Less dependent on external calibration
targets (LN2)!
RPG Microwave Technology SAC,

17. Auto-calibration receivers (III): 90+150 GHz system
Achieved System Noise Temperatures:
(incl. noise injection coupler, Dicke switch, isolator)
90 GHz: K
150 GHz: 1200 K
Full internal calibration Isolation > 30 dB
Insertion 90 GHz: 0.7 dB
Insertion 150 GHz: 1.0 dB
Allan Variance
up to 4000 s
RPG Microwave Technology SAC,

18. Auto-calibration receivers (IV): 183 GHz system
Heterodyne receiver at 183 GHz with 6 channel Filterbank
Channel centers in IF: 0.6, 1.5, 2.5, 3.5, 5.0, 7.5 GHz
Noise injection for calibration
Tsys=1200 K for complete radiometer
Tsys=380 to 450 K for mixer
Schottky mixer diode by ACST (Germany)
Dome-C, Antarctica
3.300m asl, -25 to -80 °C
Close to South-Pole
Similar System on HAMP
(HALO Microwave Package)
for HALO research aircraft
RPG Microwave Technology SAC,

19. Schottky Mixer and Multiplier Improvements
Planar technology
Discrete Schottky devices
Semi-integrated and full integrated structures
Two collaborations:
STFC/RAL, UK
ACST, Germany
Mandatory improvements
for 800 to 1000 GHz
circuit mountings:
Reduced Cj0
Reduced Cstr
Smaller size
ESTEC Contract 22032/08/NL/JA: Sub-Millimeter Wave Receiver Front-End (at 664 GHz)
ESTEC Contract 21628/08/NL/GLC: Integrated Schottky Structures (at 664 GHz)
RAL Diode
Air-bridge
Mesa with
anode
Anode pillar
(contact pad)
Cathode pillar
Back-side ohmic
Membrane-
substrate
Air-bridges
Mesas
Protection pillars
(contact pads)
25μm
50μm
ACST Diode
Quasi-vertical (QVD) single Diode (SD)
Anti-parallel (APD) diode
RPG Microwave Technology SAC,

20. Schottky Mixer and Multiplier Improvements
Planar technology
Discrete Schottky devices
Semi-integrated and full integrated structures
Two collaborations:
STFC/RAL, UK
ACST, Germany
Mandatory improvements
for 800 to 1000 GHz
circuit mountings:
Reduced Cj0
Reduced Cstr
Smaller size
ESTEC Contract 22032/08/NL/JA: Sub-Millimeter Wave Receiver Front-End (at 664 GHz)
ESTEC Contract 21628/08/NL/GLC: Integrated Schottky Structures (at 664 GHz)
RAL Diode
Air-bridge
Mesa with
anode
Anode pillar
(contact pad)
Cathode pillar
Back-side ohmic
Membrane-
substrate
Air-bridges
Mesas
Protection pillars
(contact pads)
25μm
50μm
ACST Diode
Quasi-vertical (QVD) single Diode (SD)
Anti-parallel (APD) diode
RPG Microwave Technology SAC,

21. Improved Diodes: Vector Network Analyzer Products
50 – 75 GHz
60 – 90 GHz
75 – 110 GHz
90 – 140 GHz
110 – 170 GHz
140 – 220 GHz
220 – 325 GHz 325 – 500 GHz
(500 – 750 GHz)
OEM
Network Analyzer Frequency Extenders
for
Rohde & Schwarz
Courtesy of Rohde & Schwarz
RPG Microwave Technology SAC,

22. Improved Diodes: Tx/Rx Products
Transmit / Receive Systems:
90 GHz 183 GHz
220 GHz 324 GHz
502 GHz 640 GHz
870 GHz
For compact ranges
(antenna measurement facilities, phase + amplitude)
Multipixel Array
220 – 325 GHz
RPG Microwave Technology SAC,

23. Improved Diodes: RPG sub-harmonic mixers
Art.-No.
RF Range [GHz]
DSB-Noise Temperature
Conversion Gain (DSB)
IF-Band- width
Required LO Power
Waveguide LO RF
SHM118
500 K
-5 dB
> 16GHz
6 dBm
WR15
WR8
SHM137
-6 dB
> 20 GHz
4-7 dBm
WR12
WR6.5
SHM150
450 K
> 16 GHz
2 dBm
SHM183
430 K
-4 / -5 dB
4 dBm
WR10
WR5.1
SHM220
> 18 GHz
SHM280
700 K
-7 dB
WR3.4
SHM300
900 K
SHM340
1000 K
-6 / -7 dB
WR2.8
SHM424
1100 K
-7/ -8 dB
7 dBm
WR4.3
WR2.2
SHM664
1600 K
-8 dB
WR1.5
RPG Microwave Technology SAC,

24. Receiver technology – 183 GHz example
183 GHz feeds and sub-harmonic
mixers for ALMA-WVR
Best 183 GHz receivers available
Built in larger numbers
Noise-injection (RPG only manufacturer world wide)
All ALMA water vapor radiometers equipped with RPG mixers and feeds
RPG Microwave Technology SAC,

25. Improved Diodes: RPG sub-harmonic mixers
Art.-No.
RF Range [GHz]
DSB-Noise Temperature
Conversion Gain (DSB)
IF-Band- width
Required LO Power
Waveguide LO RF
SHM118
500 K
-5 dB
> 16GHz
6 dBm
WR15
WR8
SHM137
-6 dB
> 20 GHz
4-7 dBm
WR12
WR6.5
SHM150
450 K
> 16 GHz
2 dBm
SHM183
430 K
-4 / -5 dB
4 dBm
WR10
WR5.1
SHM220
> 18 GHz
SHM280
700 K
-7 dB
WR3.4
SHM300
900 K
SHM340
1000 K
-6 / -7 dB
WR2.8
SHM424
1100 K
-7/ -8 dB
7 dBm
WR4.3
WR2.2
SHM664
1600 K
-8 dB
WR1.5
RPG Microwave Technology SAC,

26. Sub-Harmonic Mixer: 424 GHz
LO Power: 5 mW
Tmix=800 to 1200 K
Tsys=1800 K
(Feed, SHM, IF Amp, Detection)
Conversion= –7 dB
RPG Microwave Technology SAC,

27. Sub-Harmonic Mixer: 664 GHz
LO Power: 3 mW
Tmix ≈ 1600 K
Conversion: –7.5 to –9.5 dB
RPG Microwave Technology SAC,

28. Further Schottky Diode Optimization: InGaAs
Only at ACST: InGaAs Diode
InGaAs built-in voltage (barrier height) significantly lower than GaAs (0.2eV compared to 0.8eV)
Reduced LO power required for SHM at 183 GHz: 0.34 mW (10 dB less!)
183 GHz InGaAs mixer with 0.2 / 0.25 / 0.34 mW LO-power
183
GHz
InGaAs
GaAs
Tmix
700 K
500 K
430 K
Conv.
Loss
–6.6 dB
–5.5 dB
–4.2 dB LO
Power
0.34 mW
3.0 mW
2.2 mW
RPG Microwave Technology SAC,

29. Technical Study – SWI for EJSM
Europa Jupiter System Mission (EJSM, Laplace), NASA / ESA
Orbiter: Jupiter Ganymede (JGO)
Instrument: Submillimetre-Wave (SWI)
Situation
distance to Jupiter: km (15 RJ)
primary: mm
frequency bands: – – 1266
scanning: axis: +/- 4° (limb)
1-axis: +/- 60° (moons)
science requirement: m/s (winds in limb)
angular resolution: < 2 //
pointing knowledge: //
SWI - JGO – EJSM
ESA / NASA Mission zum Jupiter
Zwei Frequenzbänder, 2-Achsen scanning (along-track und cross track)
Hohe Pointing Anforderungen, Gewicht <10kG, hohe Strahlenbelastung nahe Jupiter
Machbarkeitsstudie von RPG beinhaltet: Mechanische Struktur, 600 GHz Empfänger Perfomance, Thermales Design 4°
65°

30. Technical Study – SWI for EJSM: Principal Setup
Incoming microwave radiation
secondary
primary
SWI-telescope
Instrument unterteilt sich in drei Teile:
Teleskopstruktur
Optisches Compartment
CTS und Elektronik in der Vault des Satelliten
receivers and optics compartment
platform
common shielded vault
electr. + synth.
CTS spectro.
other instr.
RPG Microwave Technology SAC,

31. Technical Study – SWI for EJSM Mechanical Design
secondary
primary
Zwei-Achsen Scanmechanismus
Primary drehbar für Along-track Scanning +/-65°
Gesamtes Teleskop Kippbar für Cross-track Scanning +/- 4°
along-track scanning
optics compartment
pusher
rotation axis cross-track scanning
RPG Microwave Technology SAC,

32. classical enclosed housing good radiation shielding
receiver feeds
hot load
1200 GHz receiver chain
IF-LNAs
telescope beam
Optik und Empfänger geschirmt in Gehäuse untergebracht.
Verlustarme Optik, minimaler Platzbedarf, hoher Strahlungsschutz.
Gesamtes Design von RPG
calibration flip mirror
beam splitter
Optics Compartment:
600 GHz receiver chain
low-loss Gaussian Telescope beam path
small overall size (170 x 290 mm2)
thermally stabilized mixer, PA, hot load
classical enclosed housing
good radiation shielding

33. Technical Study – SWI for EJSM: Mass Budget
Surface
primary mirror (Mg) g
actuators (all) g
receivers (both) g
telescope structure g
optics plate g
sum: g
Teleskop mit Optik nur 4210g
Komponenten in der Vault 2800g
-> gesamtes Instrument nur 7000g
Vault
spectrometers (CTS) g
electronics g
synthesizers g
common shielded vault
other instr.
sum: g
Electr. + Synth
CTS Spectro.
total: g

34. Conclusion / Summary
Direct detection with superior performance (over heterodyne) up to 120 GHz (until better MMIC LNA technology becomes available)
Auto-calibration receivers up to 200 GHz
Cooperation with Schottky diode manufacturers for improved devices
Development of improved mixers and multipliers up to 900 GHz, leading to:
VNA extenders covering all bands to 500 GHz (and soon even further)
Transmit/Receive systems up to 900 GHz
Excellent sub-harmonic mixers
Outstanding performance at 183 GHz, 424 GHz, 664 GHz
Further steps:
■ Substrate Transfer ■ High-Power varactors (driver stages for THz)
■ Film Diode Technology ■ Continuing reduction of capacities and size
Results partly supported by:
ESTEC Contract 22032/08/NL/JA: Sub-Millimeter Wave Receiver 664 GHz
ESTEC Contract 21628/08/NL/GLC: Integrated Schottky Structures @ 664 GHz
Thank you!
RPG Microwave Technology SAC,

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RPG Microwave Technology SAC,

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RPG Microwave Technology SAC,

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RPG Microwave Technology SAC,

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RPG Microwave Technology SAC,

39. RPG ESA/ESTEC/EU current activities
Ongoing ESA and Space application activities:
ESTEC “Integrated Schottky Structures” (664 GHz FE, ICI)
ESTEC “Sub-Millimetre Wave Receiver Front-end” (664 GHz FE, ICI)
EU/FP7 “Millimeter-Wave Integrated Diode & Amplifier sources” (100 GHz)
ESTEC/EUMETSAT Metop Second Generation:
„RPG Sat-B CPI coordination and interface definition support” (OHB)
MWI/ICI Receiver Performance & Test Requirements definition (TAS-I)
ESA “Cloud and Precipitation Airborne Radiometer” (118 & 664 GHz FE)
Proposal ESTEC„243 GHz Direct Detection Radiometers“
MHS from the FY-3 satellite / China
RPG Microwave Technology SAC,

40. ESTEC & RPG Dreamteam RPG Microwave Technology SAC, 2011-04-08
Schedule
Now
T 0
T0 +7
T0+14
T0+22
T0+50?
Phase 0 (MetOp SG Req.) A1 A2 B1
B2 (PDR)
C (CDR)
D (AI&T)
Technology Development
Technology Pre-Evaluation
Eval & LAT
ICI AI&T
2 Development contracts
(ongoing)
Qualified Instuments
ESTEC
ESTEC
ESTEC
ESTEC
Pre Evaluation Results
LAT Results
Instrument Design
Component Requirements
Design & Test Results
RPG
Consultancy
RPG
AI & T
RPG
Pre-Eval.
RPG
Eval & LAT
RPG ?
AI & T
Component
Requirements
ITT:
Development & sample man.
Qualified Components
ACST
Diode -manufacturing
Diodes
ACST
Diode -manufacturing
Diodes
RAL/Teratec
Diode -manufacturing
Diodes
RAL/Teratec
Diode -manufacturing
Diodes
RPG Microwave Technology SAC,

41. title A B C
RPG Microwave Technology SAC,