creating correlated 2-D noise?

Started by Rowena Lohman in Matlab DSP19 years ago

I need to create noise on a 2-D grid, say: [x,y]=meshgrid(-100:100,-100:100); where I can set the correlation length. I know...

I need to create noise on a 2-D grid, say: [x,y]=meshgrid(-100:100,-100:100); where I can set the correlation length. I know that I need to take random noise and then filter it somehow, but I don't know how to do that. I've been reading the matlab help files, but it loo


RLS & beamforming

Started by Giovanni Marino in Matlab DSP18 years ago

Hi, I'm working for my thesis, and i would ask u some info about beamforming with RLS adaptive filter. I have to simulate a...

Hi, I'm working for my thesis, and i would ask u some info about beamforming with RLS adaptive filter. I have to simulate a beamforming for 4 antennas at receiver for a signal with a DoA of 0? and an interference with a DoA of 0? and 60?. The priori error formula, at n-th step


Hilbert Transformer Design

Started by mariscal_murat in Matlab DSP17 years ago

Hello, i?m new, excuse me, my english is very bad. Have anybody implemented a Hilbert Transformer in a DSP? In this case, what is...

Hello, i?m new, excuse me, my english is very bad. Have anybody implemented a Hilbert Transformer in a DSP? In this case, what is the algoritm used? Remez Exchange? In the other hand, What is the least order necesary to work well? I think that i can use "Filter Design & Signal Analysis" application of MATLAB for desig


filtering additive white gaussian complex noise

Started by anjankumarkundu in Matlab DSP16 years ago

i would like to filter the additive white gaussian coplex noise.please inform me about the filters available to eliminate the above noise.I am...

i would like to filter the additive white gaussian coplex noise.please inform me about the filters available to eliminate the above noise.I am doing my coding with Matlab. Anjan Kumar Kundu Professor University of Calcutta India


[Fwd: Re: Re: problem in normalization factor in low pass filter implementation]

Started by Jeff Brower in Matlab DSP20 years ago

Premkiran Mannava- Thanks for your inquiry. I don't think I can help with this. Please reply to the group. Jeff Brower ...

Premkiran Mannava- Thanks for your inquiry. I don't think I can help with this. Please reply to the group. Jeff Brower DSP sw/hw engineer Signalogic -------- Original Message -------- Subject: Re: [matlab] Re: problem in normalization fact


90 degree phase shifter for 60Hz

Started by mehm...@gmail.com in Matlab DSP12 years ago

Hi, I?m trying to implement hilbert filter with a narrow ripple and my limited processing power. TW = 35; % Transition Width 35...

Hi, I?m trying to implement hilbert filter with a narrow ripple and my limited processing power. TW = 35; % Transition Width 35 Hz Apass = 0.02; % Passband Ripple (dB) -> variation 0.1% Fs = 1024; % Sampling Frequency h = fdesign.hilbert('TW,Ap', TW, Apass, Fs); Hd = design(h, 'equiripple'); Hhilb = FilterStructure: 'Direct-Form FIR' Arithmetic:


FFT vs freqz

Started by divya_8910 in Matlab DSP18 years ago 1 reply

hi, i have a low pass filter and i plotted the frequency response using freqz and fft and got diff plots... ...

hi, i have a low pass filter and i plotted the frequency response using freqz and fft and got diff plots... b=remez(102,[0 0.5 0.6 1],[1 1 0 0]); B = fft(b,1024); P = B.*conj(B); t=(pi/512)*[0:511]; figure(1); semilogy(t,P(1:512),'Color',[1 0 0.


two dimensional tracking

Started by mohan prasad in Matlab DSP19 years ago

Hi everyone, I am working on a kalman filtering problem,but i don't understand how this algorithm is being used for two ...

Hi everyone, I am working on a kalman filtering problem,but i don't understand how this algorithm is being used for two dimensional tracking of the position variables.Unlike LMS,NLMS and RLS algorithm I couldn't figure out what's going on in this kalman filter as it is co


frequency transformation for filter design

Started by fara...@yahoo.co.uk in Matlab DSP13 years ago 1 reply

Hello, I am designing some bandpass filters, starting from a normalized low-pass Butterworth approximation. I have the nominator and the...

Hello, I am designing some bandpass filters, starting from a normalized low-pass Butterworth approximation. I have the nominator and the denominator of the transfer function. With: tf(nom,den); I get the transfer function. How can I change the variable s to variable s1=Q*(s/w+w/s)? On the other hand, how can I change the order of teh values in a vector? For example if I have ...


matched filtering

Started by pavel_qmed in Matlab DSP14 years ago 1 reply

Hi, I need to know 2 things: 1) the matlab command (if there is any) for 'Matched filtering'. 2) mathematical expression of 'linear Chirp...

Hi, I need to know 2 things: 1) the matlab command (if there is any) for 'Matched filtering'. 2) mathematical expression of 'linear Chirp signal' for Radar systems. I need to compress a linear chirp signal by match filter and display a compressed pulse. Hope I would be assisted. Thanks.


How to calculate Relative Power

Started by abdulhaseeb86 in Matlab DSP12 years ago

I want to calculate relative power of two signals what is the correct matlab code to do that. Actually one signal is the filtered version of the...

I want to calculate relative power of two signals what is the correct matlab code to do that. Actually one signal is the filtered version of the other, because i want to find the power contained in the specific band of frequencies. The code I am trying to use is this: x = wavread('sc4012_subj1_Pz-Oz.wav'); %Filter Specs n=10; Wn=[8 12]/50; [b,a] = butter(n,Wn,'bandpass'); x_fil = filt...


Noise filter

Started by Rajmathi S in Matlab DSP19 years ago

Hello Everybody, I'm working on noise elimination from speech signal. I've implemented Spectral subtraction concept. This...

Hello Everybody, I'm working on noise elimination from speech signal. I've implemented Spectral subtraction concept. This eliminates all noise in silence regions, but impulsive noise (such as door bang etc.) within the speech frames have not been removed. I tried spectral smoo


Frequency division multiplexing

Started by susan_w_burke in Matlab DSP18 years ago

Dear Sir: I am simulating a frequency division multiplexing of K channels. The sources are random integers. The modulation is...

Dear Sir: I am simulating a frequency division multiplexing of K channels. The sources are random integers. The modulation is QPSK. =What kind of lowpass filter shall I use? =How shall I do the frequency shift (expj?) in simulink? Should I do it in frequency domai


Multipath Channel in CDMA

Started by najmy in Matlab DSP15 years ago

Hi there, Right now, I'm doing simulations on multiuser detection (MUD) receiver for CDMA system under the multipath noise channel specifically...

Hi there, Right now, I'm doing simulations on multiuser detection (MUD) receiver for CDMA system under the multipath noise channel specifically using the Rayleigh fading channel. Two of the MUD receivers that are used for the performance comparisons are the linear decorrelating detector (LDD) and matched filter (MF). The problem is, I'm not sure whether my design are accurate or not theo...


Frequency response plotting

Started by Ahmed Shahein in Matlab DSP15 years ago 2 replies

Usually I am using the following 3 lines for plotting filter frequency response; [H F]=freqz(x, [1], 2^10, Fs); Mag =...

Usually I am using the following 3 lines for plotting filter frequency response; [H F]=freqz(x, [1], 2^10, Fs); Mag = 20*log10(abs(H)); plot(F, Mag); So, I tried to put them in a single Matlab function instead of declaring all of them each time in the scripts, but when I am using it as a function I got this error ??? Subscript indices must either be real positive integers or logical...


Simple butter filtering question!

Started by sauw...@gmail.com in Matlab DSP14 years ago 1 reply

Hello everyone, I was wondering if anyone could give me their insight to this problem. I am trying to understand how to use a bandpass filter...

Hello everyone, I was wondering if anyone could give me their insight to this problem. I am trying to understand how to use a bandpass filter in butter to pass only a certain band of frequency. This works for a simple cosine with one frequency, but with a summation of cosines.. dt=.001; %sampling rate Fs=1/dt; %sampling freq HalfFs=Fs/2; t=-10:dt:10; m=cos(2*pi*49*t)+cos(2*pi*50*t); ...


FFT of rectified signal

Started by nasti20002001 in Matlab DSP16 years ago

Hello Dear All; I am just wondering how the fft of rectified signal is different from raw signal.In fact,I am getting the same result ,when I...

Hello Dear All; I am just wondering how the fft of rectified signal is different from raw signal.In fact,I am getting the same result ,when I pass the raw signal fron HP filter and when not.I appreciate so much your help. Regards; Nastaran


Modeling a Rician channel

Started by Morris Vian in Matlab DSP12 years ago

Hi, I am trying to use the ?ricianchan? command to create my fading channel and then use the ?filter? command to obtain my received...

Hi, I am trying to use the ?ricianchan? command to create my fading channel and then use the ?filter? command to obtain my received signal after the channel e.g. %Creates channel response chan = ricianchan(Ts, 5, 0, [0.0 -1.0 -2.0 -3.0 -8.0 -17.2 -20.8], [0 30 70 90 110 190 410].*10^-9); %Filters transmitted signal through channel rxSig = filter(chan, txSig);


Raised cosine

Started by sairamesh90 in Matlab DSP19 years ago

Hi, I am developing a common receiver structure for UMTS and GPS. I have the following doubt, My problem is that 1. In the...

Hi, I am developing a common receiver structure for UMTS and GPS. I have the following doubt, My problem is that 1. In the transmitter section the data sequence should be passed thorugh a square root raised cosine filter to reduce ISI, for UMTS for GPS It is a rectangle,


8-PSK simulink simulation

Started by Giovanni Marino in Matlab DSP14 years ago

Hi, I am simulating a 8-PSK modulation in simulink. I am working in base-band, for this reason I obtain a complex number like exp(i*pi/4*k), for...

Hi, I am simulating a 8-PSK modulation in simulink. I am working in base-band, for this reason I obtain a complex number like exp(i*pi/4*k), for each clock period. I want to Upsampling this complex signal, in order to limit the signal bandwith and after I want to filter it with an SRRC (suqre root raise cosin), before sending it in my channel. Well, my problem is that I get this error from ...