manthan_genious,
Perhaps this needs to be said and is past due. If you are indeed working with frequencies up at 170,000,000,000Hz then you are essentially charting new territory. I doubt that you are doing military work since they would probably hire seasoned RF veterans for such a task. And I doubt you are doing commercial work since it would be very impractical to forge into 170GHz bands when their is plenty of usable frequencies much lower. So I guess I would asses that you are working at a university. It seems to fit the mold forging new territory, large budget and smart but inexperienced help.
The point is you are not at all likely to find someone in a forum that has also been working at 170GHz. Engineers working at 50GHz are very rare but we have one of those in Dave.
My point is this, we may be able to tell you what works at much lower frequencies but we do not know what is practical at 170GHz. There are no off the shelf parts for 170GHz. There are hardly any if any custom parts made for 170GHz. And I have never even seen an instrument capable of looking at 170GHz without aliasing. I do wish you good luck with your project but you need to understand that your questions are not readily and simply solved. My guess is that there is a lot of trial and error in your future.
