Direct Convert and IQ RADARs

Radwan,

Thank you for the question.   It’s not a straightforward answer.   Functionally it can be done,  the rest depends on the specs you are trying to achieve and choices in the implementation.  

This app note attempts to describe some things to think about: http://www.analog.com/en/technical-articles/a-review-of-wideband-rf-receiver-architecture-options.html

The AD9208 is an example of an ADC that can do direct RF sampling.   For direct conversion (using a quadrature demodulator with analog IQ), the errors in quadrature have to be understood or corrected.   Direct conversion is used in our transceiver product line where embedded algorithms can correct IQ mismatch errors.

Dear Pdelos,

Thank you very much for your clarified response.

Would you please advise me, if I want to start a new project in designing a prototype of x-band radar what is the best and easiest architecture to use?

Best regards

With available parts today, a mixing stage will likely be required.   You could do a single mix, then sample with one of our high speed converters or a transceiver.