Why Are Phase Modulation Transmitters Rarely Used in Broadcasting?

  • Thread starter Thread starter saikatmajumder
  • Start date Start date
  • Tags Tags
    Modulation Phase
Click For Summary

Discussion Overview

The discussion centers on the reasons why phase modulation (PM) transmitters are rarely used in broadcasting compared to frequency modulation (FM). Participants explore the technical challenges and applications of PM in various contexts, including digital data transmission.

Discussion Character

  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant notes that PM has been used in two-way radios historically, suggesting its practical applications in specific contexts.
  • Another participant argues that PM is better suited for transmitting discrete phase states, particularly in digital data applications, and mentions QAM as a common modulation technique that combines amplitude and phase.
  • A telecom engineer points out that PM requires a more complex receiver due to phase ambiguity, which makes it less favorable for broadcasting compared to FM.
  • One participant expresses agreement with the complexity argument, adding that high-level modulation can lead to difficulties in distinguishing phase states and that multipath propagation could introduce additional phase-related issues.

Areas of Agreement / Disagreement

Participants express differing views on the suitability of PM for broadcasting, with some agreeing on the complexity and challenges associated with PM, while others highlight its applications in digital data transmission. The discussion remains unresolved regarding the overall preference for FM over PM in broadcasting contexts.

Contextual Notes

Participants mention various technical challenges, such as phase ambiguity and the effects of multipath propagation, but do not provide a consensus on the implications of these challenges for broadcasting applications.

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.
 
Engineering news on Phys.org
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
 

Similar threads

Replies
5
Views
2K
  • · Replies 39 ·
2
Replies
39
Views
5K
  • · Replies 68 ·
3
Replies
68
Views
7K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 11 ·
Replies
11
Views
5K
Replies
5
Views
1K
  • · Replies 15 ·
Replies
15
Views
5K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 10 ·
Replies
10
Views
8K