can anyone tell me what are the basic modules of a speed radar?

also what are the various elements of speed radar as well as programmable logic control in speed radar?

 

By modules, are you looking for something like a block diagram?

Here is a link to a radar gun site - http://www.radarguns.com/how-radar-guns-work.html.

 

yes, by modules i mean i ma looking for a block diagram of a speed radar.

also pls direct me to a detailed circuit working of a frequency comparator.
does a speed radar ( a pulse radar) employ a freq comparator circuit?

 

If you read the information at the linked site, you can make your own block diagram.