Need help in detemining the signal stength Coaxial Cable

I want to develop a system which can measure the power level of each carrier ( Scale is 0- -150 db ) used for Tv Transmission.If there is any resources please let me know.And any working idea for the same is most welcome..
Thanks in advance
Vitebi

POWER LEVEL MEASUREMENT

I think that any engineer would like to have a spectrum analyzer with 150 dB dynamic.
This is not possible due to the saturation of the active devices on one side and the noise on the other side.
If you need only to measure THE LEVEL of a signal not taking care about harmonics, other carriers, etc ( i.e. acting like a microwattmeter ) you can use analog devices AD8309; it is not expansive ( some free samples available from A.D. ) and very accurate with about 100 dB dynamic.
I have used it in the Matiaz Vidmar spectrum analyzer with very good results for my personal hobby and to measure the direct/reflected power from the coupled branchs on a directional coupler at work, with very good results.
You can have the data sheet on internet ; use the schematics from the data sheet, but take a lot of care on grounding ( it can self oscillate with nothing !!!! )
Hope to be helpful.
Bye