Hi

I would like to know if each receiver's modulation has some noise figure (NF) level associated? If yes, I would like to know what is the ASK and FSK modulation noise figure ?

(For exemple, if receiver uses ASK modulation. Than, we can say that NF = x dB.)

thank you

 

Hi

I would like to know if each receiver's modulation has some noise figure (NF) level associated? If yes, I would like to know what is the ASK and FSK modulation noise figure ?

(For exemple, if receiver uses ASK modulation. Than, we can say that NF = x dB.)

thank you

Let’s see if we can clarify the issue.. For a given modulation type (ASK, FSK, PSK, etc.) the performance, measured as the probability of bit error) is determined largely by the signal to noise ratio (SNR). At the receiver, the received signal level is given by adding the transmit power, the gains of the transmit and receive antennas, and the path loss. The receiver noise (except for external noise) is determined by the noise figure and the receiver bandwidth, usually somewhat greater than the bit rate. The type of modulation and the noise figure both relate to the communications link performance, but they are not related. There are numerous books and on-line tutorials that treat the mathematics of error probability as a function of SNR,



The required bit error probability is determined by the application. Obviously a higher error probability can be tolerated by a garage door opener than by a link controlling a nuclear reactor.

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The progression from ASK to FSK to PSK corresponds to an increase in hardware complexity in exchange for improved error probability performance. Another direction for improvement of the message error performance results from encoding the information to be sent. This may be as simple as repeating the message (pressing the garage door opener button twice) or may involve extensive digital processing.



I’m sure that I have complicated your question, but I hope I have suggested what you should be considering.