Which modulation is better for modem usage ?

[hm_fa_da]

hi all ;

i have a Modem IC and it has different ways of modulating , QAM , DPSK , FSK ,
i want to know which of them is better in having less errors and being more stable ?


thanks.

 

[flatulent]

In general, the more bits per symbol, the more critical distortion and noise in the path between the modems become. FSK is more tolerant of group delay variations across the frequency range used. PSK and QPSK is more tolerant of noise.

If you are using your own set of wires between the modems you can use any mode. If you are going through the telephone system or a wireless path of your own design the FSK is a safe selection.

In the absence of any measurement equipment you can use to test the path, experimenting with all of the modes will tell you which ones have the lowest error rate for your use.

 

[suvendu]

i think FSK is suitable for modern uasges.it is less prone to error.

 

[omara007]

MSK is a special case of FSK that may suite the modem ..