Is this a Reasonable Model for Broadband Noise?

Started by junoexpress in comp.dsp13 years ago 4 replies

Hi, In part of modeling a communications system, I need to incorporate a broadband interference source. The model of interest is a source...

Hi, In part of modeling a communications system, I need to incorporate a broadband interference source. The model of interest is a source which generates Gaussian noise whose bandwidth and total power are specified. I am thinking of doing this by using the following model for a discrete signal by letting: n = time index at which signal is sampled dt = uniform time between samples w = 2...


algorithms for fat-tailed random noise generators?

Started by Ron N. in comp.dsp13 years ago

I would like to experiment with chaotic noise versus Gaussian noise sources. Previous threads in comp.dsp have recommend summing 12...

I would like to experiment with chaotic noise versus Gaussian noise sources. Previous threads in comp.dsp have recommend summing 12 uniform RNG's to approximate Gaussian random noise, which can be done with a reasonably small computational overhead per sample. Does anyone know of any reasonably low overhead algorithms to generate random noise samples from an approximation to fat-tailed, ...


PULSE DURATION ESTIMATION FROM THE OUTPUT OF MATCHED FILTER

Started by okutan in comp.dsp12 years ago 5 replies

Hi to everybody, As you can understand from the subject, i am trying to estimate durations of the pulses from the output of the matched filter....

Hi to everybody, As you can understand from the subject, i am trying to estimate durations of the pulses from the output of the matched filter. Let me explain you the problem. I have pulses that are seperated in time enough under 10 dB SNR white gaussian noise. The nominal pulse durations are 0.45 microseconds. However they may come 0.15 microseconds less than 0.45 microseconds. These narrower ...


Gaussian Noise Generation

Started by Chris Barrett in comp.dsp12 years ago 41 replies

I'm trying to generate noise within a certain spectral range. I believe such noise is called Gaussian noise. Is there a way I can do this...

I'm trying to generate noise within a certain spectral range. I believe such noise is called Gaussian noise. Is there a way I can do this other than by filtering white noise?


MATLAB Gaussian Noise Generator, variance and power density

Started by uvbaz in comp.dsp12 years ago

Hi, I'm trying to use the "Gaussian Noise Generator" under Simulink 6.3(R14SP3). There are something I dont understand. 1. Is there any...

Hi, I'm trying to use the "Gaussian Noise Generator" under Simulink 6.3(R14SP3). There are something I dont understand. 1. Is there any mathematic formula to calculate the "Noise Power Density" from the parameters "mean value(I set this to zero)", "variance", and "sample time"? 2. What's the sample rate mean? Should it be the same with the sample rate of signal, or the sample rate of ...


Auto power spectrum

Started by pa1kumar in comp.dsp12 years ago 2 replies

hi, I have created a random binary noise using 2 methods. My main aim is to create a random binary noise whose auto power spectrum rolls of at...

hi, I have created a random binary noise using 2 methods. My main aim is to create a random binary noise whose auto power spectrum rolls of at 1Hz(cut off) and the attenuation should be sharp which is my spectrum pass band should end near 2Hz. first method: I used a random gaussian noise by a sampling frequency 40Hz and compared it with sinusoidal signal whose frequency is 0.3Hz with an a...


Additive White Gaussian Noise Question

Started by Necronomicon in comp.dsp12 years ago 34 replies

My understanding is that when you add AWGN to a carrier, you make the amplitude a gaussian distribution, and then add white noise to this (not...

My understanding is that when you add AWGN to a carrier, you make the amplitude a gaussian distribution, and then add white noise to this (not really pure white noise, but as high a BW as your simulation can handle). However, if you amplitude modulate a carrier by any AM % modulation, then your Fourier transform will show side bands which will not be spectrally flat like the added white n...


Re: Soft Decision Viterbi Decoding?

Started by John in comp.dsp12 years ago 14 replies

On Dec 19, 4:09 pm, "ssohaib" wrote: > Hi, > Good to see your reply. Just take a practical example of simulating this > Viterbi Soft...

On Dec 19, 4:09 pm, "ssohaib" wrote: > Hi, > Good to see your reply. Just take a practical example of simulating this > Viterbi Soft Decoder in Matlab or any other language. > > I am using QPSK as a modulation scheme and we have rayleigh fading channel > with white gaussian noise. Now the steps i am following are: > > Data --> convolutional coding (K=3, rate=1/2) --> QP


which should have higher entropy?

Started by Todd in comp.dsp12 years ago

I made a similar post sci.image.processing a while back. I'm trying to understand why a my natural images are higher entropy than...

I made a similar post sci.image.processing a while back. I'm trying to understand why a my natural images are higher entropy than uniform noise. The order from lowest to highest is constant (0 obviously), uniform noise, LPF'd image, same image not LPF'd, gaussian noise My theoretical calculation for uniform noise agrees with what I'm getting -- about 1/256*log2(256)*241^2. Now there a...


Walsh Hadamard Transform - O'Connor transform to Gaussian Noise ( invertible )

Started by Thiophene in comp.dsp12 years ago

Some source code relating to the Walsh Hadamard transform and the O'Connor transform. http://code.google.com/p/lemontree/downloads/list

Some source code relating to the Walsh Hadamard transform and the O'Connor transform. http://code.google.com/p/lemontree/downloads/list


gaussian noise in MIMO system

Started by totohaha in comp.dsp12 years ago 5 replies

I want to simulate a MIMO system in Matlab, can anybody tell me how to add gaussian noise for a MIMO system given EbNo(in dB), say M*N, how...

I want to simulate a MIMO system in Matlab, can anybody tell me how to add gaussian noise for a MIMO system given EbNo(in dB), say M*N, how to caculate the noise variance and the standard deviation?


Newton-Rapshon method over a multiplicative or modulated noise process

Started by booboojerkers in comp.dsp12 years ago 1 reply

I am trying to implement a newton-raphson iteration to estimate sinusoidal frequency mixed with noise. Here's the problem statement: A white...

I am trying to implement a newton-raphson iteration to estimate sinusoidal frequency mixed with noise. Here's the problem statement: A white Gaussian noise process w(n) with variance sigma^2 = 1 is modulated by a sinusoid cos(2pif0n)*w(n) to yield the data set x(n) = cos(2pif0n)*w(n), n = 0, 1, ... , N-1, where N = 1000. The frequency f0 of the sinusoid is kno...


radar's signal processing

Started by umair039 in comp.dsp11 years ago 4 replies

hi i am working on the processing of radar signals,, i have a constant PRI(pulse repitition interval) radar and i take (say 40)pulses ,...

hi i am working on the processing of radar signals,, i have a constant PRI(pulse repitition interval) radar and i take (say 40)pulses , calculate their difference histogram to identify peaks(in a histogram), from peak i can calculate the incoming pulses' PRI i want to ask if i add a gaussian noise in my incoming radar signal pulses, its difference histogram is spread-out, and the peaks are no...


Sampling a signal corrupted by AWGN

Started by RIMalhi in comp.dsp11 years ago 10 replies

Let us assume that we have a bandlimited signal (with maximum frequency f_n) corrupted by additive white Gaussian noise. Before we can sample...

Let us assume that we have a bandlimited signal (with maximum frequency f_n) corrupted by additive white Gaussian noise. Before we can sample this signal, we pass the signal through an ideal anti-alias filter with cut-off frequency f_c > =f_n to avoid noise aliasing. The output of the anti-aliasing filter is fed into a matched filter matched to the symbol rate, (1/T)> =2f_n (i used f_n here because


gaussian noise

Started by charanchar in comp.dsp11 years ago 11 replies

have u got any solution for getting gaussian noise(100 samples) with exactly zero mean and variance=1 in matlab?

have u got any solution for getting gaussian noise(100 samples) with exactly zero mean and variance=1 in matlab?


How can I simulate non-Gaussian noise?

Started by jjdoc in comp.dsp11 years ago 5 replies

I'am studying robust methods for processing power electrical signals in non-Gaussian noise. I know the mostly used method is M-Estimator and...

I'am studying robust methods for processing power electrical signals in non-Gaussian noise. I know the mostly used method is M-Estimator and have already implemented an algorithm to analyze power harmonics. But how can I evaluate it and compare it with other non-robust methods. Besides impulsive noise, is there any other non-Gaussian noise? How can I simulate them? Thanks in advance!!!!!...


Computing Moving Average filter's coefficients

Started by Flashman in comp.dsp11 years ago 18 replies

Hello everyone, first, please excuse me for spelling or grammer mistakes. I was asked to estimate ,with Matlab, an MA filter's (FIR...

Hello everyone, first, please excuse me for spelling or grammer mistakes. I was asked to estimate ,with Matlab, an MA filter's (FIR filter) coefficients only from 10,000 output data samples (y(t)) which I've been given on a DAT file. The filter is a 3rd order filter, so i need to compute b0, b1, b2, b3 coefficients. The input signal x(t) is a white gaussian noise: x= rand(1,10000) ...


PSD of white noise NOT flat?

Started by BreadPaPa in comp.dsp11 years ago 4 replies

Hi, all, I would like to generate a white noise whose power spectral density is 1( flat over all frequency). I used Matlab function wgn to get...

Hi, all, I would like to generate a white noise whose power spectral density is 1( flat over all frequency). I used Matlab function wgn to get it: wn=wgn(1,10000,1,'linear'); Does the function above generate a white gaussian noise whose PSD is 1? Then I did simple experiment to check its PSD. I used Matlab function periodogram without any window: [p,w]=periodogram(wn); figure; p...


Variance of Gaussian Noise

Started by sasuke in comp.dsp11 years ago 13 replies

Does Gaussian Noise have the highest variance among all possible noise distributions? Is there a way to prove it??

Does Gaussian Noise have the highest variance among all possible noise distributions? Is there a way to prove it??


white noise power

Started by sauravrt in comp.dsp10 years ago 5 replies

Matlab command y1 = wgn(100,1,10) generates a column vector of length 100 containing real white Gaussian noise of power 10 dBW. How can I...

Matlab command y1 = wgn(100,1,10) generates a column vector of length 100 containing real white Gaussian noise of power 10 dBW. How can I verify that the power of the 100 samples is 10 dBW ?