How to Evaluate Multiple Access Interference in Time-Hopping PPM Systems?

AI Thread Summary
To evaluate multiple access interference in Time-Hopping Pulse Position Modulation (PPM) systems, it's essential to analyze the mean and variance of the transmitted signal, but this is just a starting point. Factors such as signal cross-correlations, protocol retry algorithms, transmission burst lengths, and the probability of simultaneous transmissions also significantly impact interference statistics. The choice of multiple access protocols, like CSMA or TDMA, must be considered in calculations. The use of a correlation receiver in conjunction with Time Hopping and multipath fading models will further refine the analysis. A comprehensive approach that includes these elements will provide a clearer understanding of the interference in the communication system.
T.Engineer
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in order to evaluate the Multiple Access interfernce should I find the mean and variance for the transmitted Signal?
Thanks alot!
 
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At least those, though often it's necessary to look at
other aspects of things like the signal crosscorrelations,
the protocol retry algorithms / protocol timings / packet or
transmission burst lengths, FEC coding, probability of
simultaneous transmissions, etc. etc.

Basically it depends a lot upon the protocols, the
modulation schemes, and the configurations of the
transmitters/receivers what the actual interference
statistics will be.
 
xez said:
At least those, though often it's necessary to look at
other aspects of things like the signal crosscorrelations,
the protocol retry algorithms / protocol timings / packet or
transmission burst lengths, FEC coding, probability of
simultaneous transmissions, etc. etc.

Basically it depends a lot upon the protocols, the
modulation schemes, and the configurations of the
transmitters/receivers what the actual interference
statistics will be.

Please, what do you mean by Protocols?
I am going to use Pulse Position Amplitude Modulation and correlation receiver.
and if I will find the crosscorrelation for the transmitted signal, what it will be the point?
So, what I have to do?
Thanks a lot!
 
T.Engineer said:
Please, what do you mean by Protocols?
I am going to use Pulse Position Amplitude Modulation and correlation receiver.

You said "multiple access", so xez and I assume you mean multiple transmitters colliding a a receiver. There must be some protocol for multiple access (CSMA, TDMA, etc.), so you must factor the protocol into your calculations.
 
yes exactly.
I am going to use Time Hopping format for multiple access and multipath Fading Channel model.
if you want any other information, please tell me.
Thanks alot!
 
In other word I'd like to evaluate the multiple access interference for a communication system using time hoping format and Bi- orthogonal pulse position modulation or pulse position modulation.
So, generally What I should do?
 
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