L-Band Input RF-MUX 900-2200MHz using SPDT, High ISolation Switch Matrix

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Question Hi,
 We need to replace HF relays to build a 4-to-1 input RF mux on a satellite 
 receiver. 4 antenas inputs, levels between -65 and -20dBm, 75Z, directly coming 
 from LNB. Do very low level. No nood to pass DC, but good isolation and lowest 
 insertion loss and very low noise floor (betcause of the so low RF levels) are 
 required. We plan to base that input mux on 3x HMC348 devices. Is it the best 
 AD device choice for that requirement ? Whould you suggets to use only 2 
 devices connecting RFC pins close together ? Any comment/suggest/application 
 schematics that could help ? 
 Technical Specifications- 
 75Z system
 Application: Satellite TV for South America
 Specifications
 · Insertion Loss <= 0.5dB at 1 GHz, 0.6dB at 2.2GHz
 · P1dB no constraints
 · Settling time no constraints
 · Isolation between 2 inputs (>75dB at 1 GHz)
 Answer The HMC348LP3E could be suitable for this application but it was discontinued 
 unfortunately. 
 The HMC349ALP4CE is the replacement part recommended. The HMC349ALP4CE offers 
 high isolation and low insertion loss but it was designed and specified for 50 
 ohm systems. It will still be functional in the 75ohm systems but the its 
 performance might be degraded. We can recommend you to evaluate this part in 75 
 ohm test system for comparing the RF performance in your application.
 
 The HMC8038 is our new high performance SPDT switch planned for RTS in Oct’15 
 and could be the another candidate for this application. Attached is the 
 preliminary datasheet for our HMC8038, the engineering samples are currently 
 available. Again this part was designed and specified for 50 ohm systems so the 
 customer should evaluate the part to see the performance in the 75 ohm test 
 system. (3x SPDT will provide in general a better isolation and lower 
 cross-talk compared to directly going for an SP4T switch)

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