## Forums Search for: OFDM

## PAPR

Hello, Can anyone advice me to find the right way to calculate PAPR of multicarrier systems? I am currently working on PTS technique of OFDM....

Hello, Can anyone advice me to find the right way to calculate PAPR of multicarrier systems? I am currently working on PTS technique of OFDM. The peak average power ratio, is deifned by many in many ways. Can anyone post a nice algorithm to do this???Thank you in advance.

## Plotting CCDF

i want to plot the CCDf of the ofdm signal i have calculated my peak to average power as meanSquareValue = Y4'*Y4/length(Y4); peakValue =...

i want to plot the CCDf of the ofdm signal i have calculated my peak to average power as meanSquareValue = Y4'*Y4/length(Y4); peakValue = max(Y4.*conj(Y4)); where Y4 is the fft of the signal ...how should i proceed Regards

## scrambler and descrambler in MB-OFDM

Hi, can anybody help me how to develop a code for the above subject? I know that scrambler is available in simulink blockset but can we extract...

Hi, can anybody help me how to develop a code for the above subject? I know that scrambler is available in simulink blockset but can we extract the code from there since I don't want to used simulink. please, really need your help, TQ. N'Na.

## rayleigh fading.m

hi, i would like to know if anyone have a rayleigh fading programming in Mfile format. i want to apply it on OFDM system and...

hi, i would like to know if anyone have a rayleigh fading programming in Mfile format. i want to apply it on OFDM system and plan to show the frequency offset due to the doppler shift. i really hope anyone can help me... thank you so much.. husn

## normalized power spectral density

hi i am working on OFDM .....i can represent the overlapping subcariers using the following code x = -60:0.01:60 for i=2:1:6 ...

hi i am working on OFDM .....i can represent the overlapping subcariers using the following code x = -60:0.01:60 for i=2:1:6 % Y=(dn(i)*sinc(x-i)); Y1=Y+Y1; plot(x,Y,'b--'); hold on; end where dn is array of complex numbers that are QAM modulated.......i want to ask that multiplying the sinc function with a complex numbers resul...

## IFFT for OFDM

I write this code to get IFFT for y but only spectrum drawn not time domain siganal ploted: t = -5:0.001:5; y1 =...

I write this code to get IFFT for y but only spectrum drawn not time domain siganal ploted: t = -5:0.001:5; y1 = sin(pi*(t+1))./(pi*(t+1)); y2 = sin(pi*(t+2))./(pi*(t+2)); y3 = sin(pi*(t+3))./(pi*(t+3)); y0 = sin(pi*t)./(pi*t); y11= sin(pi*(t-1))./(pi*(t-1));

## Help regarding MSE plot...

Hello all, Can anyone help me out with finding out how to plot the mean square error estimate plot... I am working on Time synchronisation...

Hello all, Can anyone help me out with finding out how to plot the mean square error estimate plot... I am working on Time synchronisation of OFDM and wish to plot MSE for the time deviations... Thanking u, Arvindhan Kumar

## the error of out of memory

inHi : I am work on QAMand OFDM modulation project, and during the simulation I get the out of memory error after the message...

Hi : I am work on QAMand OFDM modulation project, and during the simulation I get the out of memory error after the message length large than 11, so I follow the help menu's instruction to expanded the memory into 4GB, but I still get the same error, so I need some

## help for Accoustic Modem

i am doing project on OFDM channel estimation,part of that is we have to transmit data from the soundcard(speaker) and on the reciever end i have...

i am doing project on OFDM channel estimation,part of that is we have to transmit data from the soundcard(speaker) and on the reciever end i have to collect the data through mic. i am having very difficulty in the synchronization of transmitter and reciever,therefore i need help of yours in the form of ideas and matlab codes so that i can transmit from one computer and recieve data from other one...

## Powerline communication problem

Hi friends, I have been investigating on the applicability of power line communications techniques. I want to simulate the plc system in ...

Hi friends, I have been investigating on the applicability of power line communications techniques. I want to simulate the plc system in MATLAB (m file).The simulation includes FSK and PSK and OFDM modulation and demodulation , error control coding , powerline channel and the noise over it. I have some problems with these simulations . I want to know if you have any MATLAB files (m fil...

## OFDM orthogonality

inDear All; I want to plot orthogonality between sub-carriers with Matlab for five or more than five sub-carriers.If anyone have a...

Dear All; I want to plot orthogonality between sub-carriers with Matlab for five or more than five sub-carriers.If anyone have a code to plot orthogonality between sub-carriers Could you supply it to me? I look forward to your reply. Kind Regards.

## power spectral density

? Please i need? help in PSD to compare between different methods of PAPR. When apply the following code not given the same plot as in your...

? Please i need? help in PSD to compare between different methods of PAPR. When apply the following code not given the same plot as in your paper . ? My Matlab code ? N = 256;????? % length of OFDM IFFT M = 16;?????? % number of QAM constellation BW=10;??????????? % in MHz txData= randint(N,1,M); txDataMod? = qammod(txData,M); ? txDataZpadIfft = sqrt(N)*ifft(txDataMod ,N); ...

## About Pilot tones

Hi All, I have a basic doubt about pilot tones. I am working with OFDM systems and I am trying to implement pilot tones for a 64 subcarrier...

Hi All, I have a basic doubt about pilot tones. I am working with OFDM systems and I am trying to implement pilot tones for a 64 subcarrier system. I set aside 4 tones for pilot data in frequency domain. However, according to a fwe books I've read, I learn that pilot tones , which are used for channel estimation ,change their position according to some pattern (discussed in the literatur...

## need help about rayleigh fading

inhi everyone..now i started my last year project about Rayleigh Fading using OFDM system..i have a problem when using QPSK modulation..Below is...

hi everyone..now i started my last year project about Rayleigh Fading using OFDM system..i have a problem when using QPSK modulation..Below is a my coding..anybody know how to solve this prob?? %******************* Preparation Part***************************** para=128; % Number of parallel channel to transmit fftlen=128; % FFT length noc=128; % Number of carrier ...

## Zero padding problem in Simulink

I have some questions regarding implementing OFDM in Simulink... I'm using BPSK, thus my output after BPSK would be a complex number. ...

I have some questions regarding implementing OFDM in Simulink... I'm using BPSK, thus my output after BPSK would be a complex number. I've splited up the real (16 samples) and imag (16 samples) numbers into 2 matrices. I plan to use IFFT with 64 samples. Except for the DC (sample 1), Nyquist center frequency (sample 32) and the real (13~31) and i

## Sampling frequency offset correction & estimation Speth et al.

Hello everyone, I'm having troubles with SFO estimation and its correction on Speth algorithm, since I don't get correct estimated values...

Hello everyone, I'm having troubles with SFO estimation and its correction on Speth algorithm, since I don't get correct estimated values neither in AWGN nor in ideal case. Basically, I add SFO to OFDM signal through interpolation in time domain. Then trying to estimate with following code: temp_pilots_rx=[pos_pilot_symbols_rx_neg; 0; pos_pilot_symbols_rx_pos;]; % separate negative & positi...

## How to implement a PLL in MATLAB?

Is anyone know how to implement a PLL in an OFDM system using MATLAB?

Is anyone know how to implement a PLL in an OFDM system using MATLAB?

## BER for 4QAM with AWGN Channel

inhi everyone, I am trying to simulate a OFDM system with AWGN channel, 4QAM symbol in matlab. Theoritically, the curve for BER should be the...

hi everyone, I am trying to simulate a OFDM system with AWGN channel, 4QAM symbol in matlab. Theoritically, the curve for BER should be the same as for BPSK BER = Q(sqrt(2*Eb/No)); But I have a problem: When I normalized the symbols 1/sqrt(2)(1+j) (For example), that doesn't work. But when I leave out the factor 1/sqrt(r), it works perfectly. Anybody knows the answer? Please help. Th...

## Need advice on sample rate conversion

I am creating a pseudo WiMAX waveform that can be played as I/Q samples out of an arb. I've completed the framing structure and populated the...

I am creating a pseudo WiMAX waveform that can be played as I/Q samples out of an arb. I've completed the framing structure and populated the carriers with random data. I need some advice on the best way to convert a OFDM signal to the arb's faster sample rate. I have access to the Communications toolbox DSP toolbox RF toolbox I am not familiar with Simulink, so please let's j...

## Re: PAPR Reduction or Pre-distortion Techniques for OFDM

inI have gone thtough some literature on PAPR reduction techniques. Boardly i= t can be divided as: 1. Signal Processing 2. Coding (Random...

I have gone thtough some literature on PAPR reduction techniques. Boardly i= t can be divided as: 1. Signal Processing 2. Coding (Random encoding, Golay Sequence, Cyclic Code) 3. Random Scrambling (Costellation Design, Selective Mapping, Partial Trans= mit sequence) Of which I am mostly interested in the first one because that do not need a= ny change in the inner transmitter functions ...