square law power detector sensitivity values

[elektr0]

Hello,

the sensitivity gamma=Vout/Pin [mV/mW] is used to characterize the linear operating region of square law power detectors.
Performance of real detectors does always deviate from exact linear behavior, even if the input power level Pin is small (-50dBm to -30dBm).
However many authors report just the sensitivity value without informing the reader about the input power level.
Can somebody comment on this ?
Thank you very much.

-e

 

[jiripolivka]

Each detector type has its specifications. Input power level is defined by TSS, with 1-kHz modulated signal, and the detected video output can be filtered to reduce wideband noise. Such "high sensitivity" detectors are best below -20 dBm. Good detectors have the "square-law" response between the above power levels. Typical response, K or gamma, for output voltage related to input power, is 2000-3000 mV/mW.