1. Front-end characteristics
Frequency bands :
1) GHz (without H2O line 321 GHz)
2) GHz (including H2O line).
Expected receiver temp : 1500K(DSB) K(SSB)
Fixed tuning : integrated design
Schottky diodes mixer & HBV diodes tripler at ambient Temp.
Brigthness temperature (K)
Fol1
Fol2
Fol3
Fol3bis
Frequency (GHz)
2 different scenario
possibles

2. 1st architecture scenario
a single channel receiver head

3. 2nd architecture scenario
a dual channel receiver head

4. Generic architecture of a channel
coupler
Horn
Subharmonic
mixer
LNA
Tripler
harmonic
LO source
(Gunn)
PLL
Reference
Oscillator
IF signal
Spectral analysis module
Antenna
Coupler

5. Mixer design possibilities
Subharmonic mixer cell using planar Schottky diodes pair (Univ. of Virginia)
1st design (400GHz UVa design)
2nd design (MIRO-like type)
planar diode (UVa) :

6. Tripler design possibilities
HVB diodes (InP based) tripler cell (IEMN- Lille)
design (290 GHz tripler-like)
Preliminary values :
Freq. In : 56 GHz
Freq. Out : 168 GHz
Pin = mW
Pout = mW
n = 10%
HBV diodes (8 barriers) :

7. Expected performances
single channel receiver
dual channel receiver

8. Sensitivity results
single channel receiver
dual channel receiver

9. Comparison between single/dual channel design
Advantages of dual channel
Better SSB receiver noise,
Redundancy of the front-end (in case of failure).
Drawbacks
weight, space, power supply (price ?) increased
Quasi-optical alignment more complex

10. Realisation context Baseline :
Mixer development : Obs - Astrium - Virginia diodes
Multiplier : Obs - IEMN - Astrium
Low Noise Amplifier : Miteq, Chalmers
LO source :
Gunn : RPG - Farran
PLL : Omnisys, Farran

11. Frontend-Mixer Schedule