## Frequency division multiplexing

Started by 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

Started by in Matlab DSP14 years ago 3 replies

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...

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 ...

Started by in Matlab DSP12 years ago

Hi, I am trying to advance my knowledge on a QPSK communication system. I found a simulink simulation that describes a communication...

Hi, I am trying to advance my knowledge on a QPSK communication system. I found a simulink simulation that describes a communication system. I tried to contact the author, but I am assuming he is busy, since he didn't reply to me. So, I would appreiciate if someone can answer my question. In case, if you would want to look at the simulink files, it is located at: http://www.mathworks.de/m...

## OFDM USING MATLAB

Started by in Matlab DSP18 years ago

Hi Iam doing my final project in OFDM System suing QPSK modulation technique... and Iam facing real troubles dealing wiht its...

Hi Iam doing my final project in OFDM System suing QPSK modulation technique... and Iam facing real troubles dealing wiht its matlab programs !!! I have the programs already but they r not working properly ! for example , some times it shows this eror : ??? Strings passed to

## How to calculate the bandwidth for the Analog/Digital Modulations?

Started by in Matlab DSP11 years ago

Hi, I have a few doubts regarding the calculation of bandwidth for various Analog/Digital modulation, please correct me if I have gone...

Hi, I have a few doubts regarding the calculation of bandwidth for various Analog/Digital modulation, please correct me if I have gone wrong Fm=Frequency of message signal. deltaF=Freq.deviation SR= Symbol Rate AM = 2 * Fm FM = 2 * deltaF + Fm 2FSK = 2 * deltaF + SR 4FSK = 2 * deltaF + SR BPSK = SR QPSK = SR Will the Root Cosine Filter at the transmitter side will effect t...

Started by in Matlab DSP16 years ago

hello, I'm new in that kind of mailing list and ,also, in DSP so if I ask for some stupid questions or I don't ask for things properly, I'm...

hello, I'm new in that kind of mailing list and ,also, in DSP so if I ask for some stupid questions or I don't ask for things properly, I'm sorry. I'm a student and I'm trying to develope a modulator-demodulator model to implant in a DSP plateform from ALTERA with a FPGA Stratix EP1S25F780C5. In order to develope a model, and as I don't have experience, I'm following a tutorial from altera ...

## simulation of ofdm with QPSK in Rayleigh channel

Started by in Matlab DSP13 years ago

hi; i have simulated a general ofdm system but i am not having correct results. can any one rectify problems in this code. have i used correct...

hi; i have simulated a general ofdm system but i am not having correct results. can any one rectify problems in this code. have i used correct formulas in this code? i mean does RAYLEIGHCHAN command hold for it? do i need to equalize the receiver signal? if so then how and at what stage? and have i used right command for theoritical BER of OFDM in Rayleigh channel? % Script for computing the B...

## phase of rayleigh envelop

Started by in Matlab DSP14 years ago 2 replies

hi i have written matlab code for rayleigh fading using BPSK and QPSK i generate a rayleigh distribution by generating two identiaccly...

hi i have written matlab code for rayleigh fading using BPSK and QPSK i generate a rayleigh distribution by generating two identiaccly independently generated gaussian vectors and than i take a absolute value of it that gives me a rayleigh distribution..than i multiply this value with transmitted signal that gives me a rayleigh fading signal..that means i multiply amplitude of rayleigh envelop ...

## OQPSK or MSK delay problems

Started by in Matlab DSP12 years ago

Hi all! Basically my project is a bit generator+spreader+modulator --> demodulator+despreader. A 4 bit sequence is converted to a 32 chip...

Hi all! Basically my project is a bit generator+spreader+modulator --> demodulator+despreader. A 4 bit sequence is converted to a 32 chip sequence by the spreader. If I use a QPSK and without AWGN channel, I get 0 BER before and after the despreader. However when I use the MSK (or OQPSK) and I add the delay beacuse of the modulation (2 bits for OQPSK and the traceback length for the MS

## Re: LLR demodulator and APP decoder

Started by in Matlab DSP14 years ago

U can write ur own APP decoder for that using BICM concept. BR, -SaiRamesh. --- f...@tee.gr wrote: > Dear colleagues, > > is there...

U can write ur own APP decoder for that using BICM concept. BR, -SaiRamesh. --- f...@tee.gr wrote: > Dear colleagues, > > is there anybody that has connected a LLR > demodulator Simulink block (i.e. QAM, QPSK) with an > APP Decoder one? I need that to make turbo-coded > modulation simulations with Simulink either SCCC > turbo coder or PCCC ones. Simulink Help and Demos > also mainta

## multilevel modulation

Started by in Matlab DSP21 years ago

hi what does this statement means " The modem uses 16 tones and are QPSK modulated in 3-3400Hz bandwidth". is that means ...

hi what does this statement means " The modem uses 16 tones and are QPSK modulated in 3-3400Hz bandwidth". is that means 16