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
Messages
86
Reaction score
0
in order to evaluate the Multiple Access interfernce should I find the mean and variance for the transmitted Signal?
Thanks alot!
 
Engineering news on Phys.org
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?
 
I have recently moved into a new (rather ancient) house and had a few trips of my Residual Current breaker. I dug out my old Socket tester which tell me the three pins are correct. But then the Red warning light tells me my socket(s) fail the loop test. I never had this before but my last house had an overhead supply with no Earth from the company. The tester said "get this checked" and the man said the (high but not ridiculous) earth resistance was acceptable. I stuck a new copper earth...
Thread 'Electromagnet magnetic field issue'
Hi Guys We are a bunch a mechanical engineers trying to build a simple electromagnet. Our design is based on a very similar magnet. However, our version is about 10 times less magnetic and we are wondering why. Our coil has exactly same length, same number of layers and turns. What is possibly wrong? PIN and bracket are made of iron and are in electrical contact, exactly like the reference design. Any help will be appreciated. Thanks. edit: even same wire diameter and coil was wounded by a...
Thread 'Beauty of old electrical and measuring things, etc.'
Even as a kid, I saw beauty in old devices. That made me want to understand how they worked. I had lots of old things that I keep and now reviving. Old things need to work to see the beauty. Here's what I've done so far. Two views of the gadgets shelves and my small work space: Here's a close up look at the meters, gauges and other measuring things: This is what I think of as surface-mount electrical components and wiring. The components are very old and shows how...
Back
Top