help about VGA!!!

I will design a VGA in RF receiver system .but I don`t know how can begin!
anybody can help some advices?!
thanks!

what is the frequency of VGA?

You can search the papers of IEEE.

https://www.edaboard.com/ftopic308330.html

https://www.edaboard.com/ftopic308328.html

The frequency of VGA is 97MHz.
I don`t know which topologies to use!

Added after 1 minutes:


I can`t find these page.it have been deleted!


https://www.edaboard.com/ftopic308330.html

https://www.edaboard.com/ftopic308328.html

could someone give me more help!

Other specifications?

Supply voltage? Tecno?
Gain range?
Linearity at max and min gain?
Noise figure at amx and min gain?
Do you need a log-linear one?

Mazz