Any relevant info on shot noise?

[mc_psalms]

shot noise matlab

Can anybody advise on how I maybe able to simulate shot noise or provide links to good resources. Also I am looking into simulating AWGN and Rayleigh fading. Any relevant info would be much appreciated.

 

[flatulent]

Shot noise is current variations. In a SPICE type simulator you could use a resistor to generate noise and then an ideal voltage controlled current source. These type sources are a device type in the SPICE devices.

 

[GroundCtrl]

About AWGN and Rayleigh fading Simulink Communications blockset helps you.
There are special configurable models for these.

 

[mc_psalms]

Thank you for your response

GroundCtrl: I managed to simulate AWGN and Rayleigh fading in matlab. However, I am not sure if the results produced are absolutely random or whether they are simply pseudo random.

flatulent: I am right in believing that resistor must have a gassian noise distribution. I think I am still confused about the the simulation. Do you know of any good internet resources

Mc Psalms

 

[cedance]

reg. AWGN and rayleigh fading channel noises, if u are to simulate using matlab,

then,

AWGN is an additive noise, u would know. generate a signal x say of length 1000,
then the corrupted signal with AWGN is,

y = x + randn(1,1000) ; where 1,1000 will generate gaussian noise with 1 row and 1000 values.

reg. rayleigh noise, its multiplicative in general as opposed to the AWGN, so generate this noise and just multiply instead of adding. in general, for a communication system, channel is rayleigh and in addition to that, thermal noise exists.. so u have to multiply and add..

rayleegh fading noise...

y = x * randn(1,0000);

comm system,

y = x * randn(1,1000) + randn(1,1000);

incase, i misunderstood ur question/ u need something other than this, pls reply this post!

/cedance

 

[mc_psalms]

Thank you for your response

GroundCtrl: I managed to simulate AWGN and Rayleigh fading in matlab. However, I am not sure if the results produced are absolutely random or whether they are simply pseudo random.

flatulent: I am right in believing that resistor must have a gassian noise distribution. I think I am still confused about the the simulation. Do you know of any good internet resources

Mc Psalms

 

[cedance]

hi,

what is your confusion on actually? u failed to mention it in your last post. what resources do u exactly need from internet? code or theory? if code, then what exactly are u tryin to design? coz u just have asked abt the different channels and noises.

btw, matlab commands u use are seldom perfect random. they are either uniformly distributed as incase of rand(1,n) or gaussian incase of randn(1,n). i dont think there is a perfect all random number generator discovered yet! dont know thou. may be u could design your system with probability assignment of the rate of repitition..

pls explain a little more so that i would do the need ful.. to my potential.

/cedance

PS: donot post a thank you message as a reply. if u find a reply useful, its better to use the helped me button. a more betterway of showing ur gratitude. its meant for teh same! good luck

 

[truebs]

Basically shot noise is thermal noise ,hence resistors can be used to model it. Try using frictional analysis also.

 

[mc_psalms]

Okay, I am basically doing some research on the noise found in communication systems for a y assignment. I am required to talk about Rayleigh fading (slow & fast), AWGN, Shot noise and how they are simulated. I am finding it difficult understanding how to discuss the methods used to simulate shot noise.

I have come across many examples for simulating AWGN and Rayleigh fading. In particular, using Jakes sum of sinusoids for rayleigh fading and adding a random variable to a transmitted signal to produce the affects of AWGN.

I do not necessarily need code. But an understanding how code could be used would be useful.

Psalms

 

[flatulent]

All random noise has a flat spectrum and therefore a gaussian amplitude probability distribution.

 

[ofish]

Some communication books has that topics.