Help me start a zero-if GPS receiver RFIC project

hi, everyone
I want to do a project for zero-if GPS receiver RFIC, how do i start if i have the system specifications? how to select original schemetic for each unit component, such as LNA, Mixer et.al, thanks

Hi,

At first you should find the main parameters of your receiver. The efficiency of a receiver are usually evaluated by two parameters, namely, selectivity
and sensitivity.

Then place the blocks according to the zero-if architecture and calculate the desired specs.

Finally simulate and correct your design by RF tools. ADS would be a good choice.

http://smirc.stanford.edu/papers/isscc98p-derek.pdf

at present, I have the specifications, but i have not the specific component schmetic, such as LNA , mixer LPF et.al
in addition , I have the corresponding process lib too

how do i start?

Which foundry do you use? you can transfer your process library from the IC tool you are using (i.e. Cadence) to ADS if not present in ADS.