help in designing RF down conversion to IF with 500MHz BW
I have to sample frequency range from 500MHz to 3 GHz. I need IF BW of 500MHz in any center frequency in that range.
I need about 70dbc dynamic range.
I'm new in RF design and I think in first step the signal should be up converted to a upper frequency with a LO like 8 GHz then down converted to IF frequency. after that a 1 GHz ADC can be used for sampling.
does any body know that:
Is this a good solution?
Is there are any board or device that can be used for this project?
I don't quite understand. You've got a signal bandwidth of 2.5GHz, but you want to sample 500MHz BW. Are you saying you can throw away 2GHz of signal BW?
A 500MHz resolution BW does not give much information from 500 to 3000 MHz and 70dB dynamic range will be swamped by noise and pulsed multitude of transmitters without any means of identifying them.
Distortion products increase with wideband gain.
Do you just want an envelope peak detect log scale or RSSI like response?
as I said any center frequency from 500MHz to 3GHz could be selected and 500MHz around that center should be sampled. then I need a 500 MHz BW filter before sampling.
filtering could be in 2 steps. first after up conversion with 2.5GHz BW(from 5GHz ~ 7.5 Ghz) then after down conversion with 500MHz BW(from 0 to 500MHz).
after that I have a filter signal with 500MHz BW.
I also know that in this all 500Mhz will not be OK for sampling and aliasing will shows up.
this is my initial design. I asked for any better suggestions.
I NOT said "500 MHZ resolution BW"
I said 500 MHz BW for IF sampling.