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Brigthness temperature (K). Fol 3bis. Fol 2. Fol 1. Fol 3. Frequency (GHz). Front-end characteristics. Frequency bands : 1) 324-348 GHz (without H2O line 321 GHz) 2) 321-348 GHz (including H2O line). Expected receiver temp : 1500K(DSB) - 3300K(SSB) Fixed tuning : integrated design
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Brigthness temperature (K) Fol3bis Fol2 Fol1 Fol3 Frequency (GHz) Front-end characteristics • Frequency bands : • 1) 324-348 GHz (without H2O line 321 GHz) • 2) 321-348 GHz (including H2O line). • Expected receiver temp : 1500K(DSB) - 3300K(SSB) • Fixed tuning : integrated design • Schottky diodes mixer & HBV diodes tripler at ambient Temp. 2 different scenario possibles
1st architecture scenario • a single channel receiver head
2nd architecture scenario • a dual channel receiver head
Subharmonic mixer LNA Horn IF signal Antenna Spectral analysis module Tripler harmonic mixer Coupler coupler LO source (Gunn) PLL Reference Oscillator Generic architecture of a channel
1st design (400GHz UVa design) 2nd design (MIRO-like type) Mixer design possibilities Subharmonic mixer cell using planar Schottky diodes pair (Univ. of Virginia) planar diode (UVa) :
design (290 GHz tripler-like) Preliminary values : Freq. In : 56 GHz Freq. Out : 168 GHz Pin = 100-150 mW Pout = 10-15 mW n = 10% Tripler design possibilities HVB diodes (InP based) tripler cell (IEMN- Lille) HBV diodes (8 barriers) :
single channel receiver dual channel receiver Expected performances
Sensitivity results • single channel receiver • dual channel receiver
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
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