Why Are Phase Modulation Transmitters Rarely Used in Broadcasting?

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Phase modulation (PM) transmitters are rarely used in broadcasting primarily due to the complexity of their receivers, which face phase ambiguity issues compared to frequency modulation (FM). While PM has applications in two-way radios and digital data transmission, FM is preferred for its simplicity and reliability in broadcasting. Additionally, high-level modulation in PM can lead to difficulties in distinguishing phase states, especially when the modulating signal's amplitude exceeds certain thresholds. Multipath propagation also introduces significant phase-related challenges for PM. Overall, these factors contribute to the limited use of phase modulation in practical broadcasting scenarios.
saikatmajumder
Hello,
I want to know why phase modulation (PM) transmitters are not used for practical broadcasting, though its almost similar partner frequency modulation (FM) is used widely for broadcasting.
 
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PM has been used in two-way radios for many years. Probably not anymore, but at one time was common.
 
re

pm is more suited to transmit discreet phase states usually for digital data. Probably the most widely used modulation is QAM (quadriture amplitude modulation) which combines amplitude and phase shift keying to trasmit large amonts of data very quickly. The most common application is the cable modem, satellite tv, and digital cable tv.
 
Response to Phase Modulation by Jha,Shambhu Nath

saikatmajumder said:
Hello,
I want to know why phase modulation (PM) transmitters are not used for practical broadcasting, though its almost similar partner frequency modulation (FM) is used widely for broadcasting.
:zzz:

hi,

I am Telecom Engineer at Nepal Telecom,Nepal.
Response to above query:

The phase modulation necessitates complex receiver due to phase ambiguity in comparision to frequency modulation.So it is not preferred for transmmiting broadcasting.

Thanks
Jha,Shambhu Nath
e_shambhu@rediffmail.com
 
It should be, Mr. Shambhu

Thank you Mr. Shambhu,
I think it should be the reason. What I think is that if modulating signal amplitude is increased beyond certain amplitude, phase will exceed pi or 2*pi and it will be difficult to distinguish it. Thus high level modulation will be somewhat difficult.
Moreover I think multipath propagation will bring a lot of phase related problems.

its
saikat m
ec04m016@nitc.ac.in
 
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