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QPSK Spectrum in simulink

Started by dpas...@gmail.com in Matlab DSP15 years ago

Hi everyone. I just want to plot the QPSK baseband spectrum from the output data of the QPSK simulink block. However the output of this...

Hi everyone. I just want to plot the QPSK baseband spectrum from the output data of the QPSK simulink block. However the output of this block are the symbol coordenates in the signal space and when I use "spectrum scope" i don't get the theorical spectrum for the qpsk (the sinc function..). How can I do it? Can I use the qpsk block? thanks in advance!


Simulink model of a QPSK modem

Started by alda...@ensieta.fr in Matlab DSP19 years ago

Hi everybody, I'm working on a Simulink QPSK modem for a Altera Stratix platform and I'm a bit lost. Does anybody have a model in simulink of a...

Hi everybody, I'm working on a Simulink QPSK modem for a Altera Stratix platform and I'm a bit lost. Does anybody have a model in simulink of a QPSK modem that can help me developing mines? If anybody could send me a model I will be really thanked. Bye!


QPSK for BER performance

Started by centuriaky in Matlab DSP21 years ago

hi all, Below is the QPSK i have done to calculate the BER. However, the dectection part is wrong. Can anyone advise what is...

hi all, Below is the QPSK i have done to calculate the BER. However, the dectection part is wrong. Can anyone advise what is the correct syntax. Appreciate the help greatly. Thanks %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


simulating QPSK modulation

Started by mosse_adam in Matlab DSP22 years ago 1 reply

Hi, I want to simulate a QPSK transmission through a multipath channel. I see that some people use 1 sample per symbol while...

Hi, I want to simulate a QPSK transmission through a multipath channel. I see that some people use 1 sample per symbol while others use 8 or 16. Could someone give me some hints about the advantages and disadvantages of each option? I'm thinking about... - whether


QPSK

Started by hari_asv in Matlab DSP20 years ago 1 reply

Can some one get me a source code as to how i go about simulating qpsk symbols? The constraints are: symbol rate - 1 /sec and...

Can some one get me a source code as to how i go about simulating qpsk symbols? The constraints are: symbol rate - 1 /sec and chip rate is 128sec.


QPSK or BPSK for ZF equalization

Started by pado...@libero.it in Matlab DSP19 years ago

Hi all!! I implemented in Matlab some different ZF equalizations, but I should change the input signal froma random [+1/-1] signal to a QPSK...

Hi all!! I implemented in Matlab some different ZF equalizations, but I should change the input signal froma random [+1/-1] signal to a QPSK or BPSK signal (choosing number of samples, oversampling and so on..), but I have no idea of how doing it. Could anyone give me some advices or some code-examples? Thank you all in advance, Ella PS:here there


measuring Baudrate from QPSK signals

Started by bochao76 in Matlab DSP18 years ago 2 replies

Good morning, does anybody has an idea, how to measure the baudrate also known as the symbolrate of a QPSK signal - I have a Real-Array and...

Good morning, does anybody has an idea, how to measure the baudrate also known as the symbolrate of a QPSK signal - I have a Real-Array and an Imag-Array of data-streams? 1. How should I proceed? 2. Is finding zero-crossing from the signal a good approach? 3. Does anybody has source-code concerning this . Thanx a lot in advance for your support. Best regards. Bochao


Passband QPSk modulator...simul

Started by k_ajay1 in Matlab DSP22 years ago

Hi, I am having a weird problem with a passband QPSK simulation I am working on. I just need the modulated output for further...

Hi, I am having a weird problem with a passband QPSK simulation I am working on. I just need the modulated output for further pprocessing and dont want the demodulation in my simulation. When I just use the M-PSK modulator the transmitted output is like a square wave. When ther


Qn on QPSK demodulation

Started by ying...@yahoo.com.sg in Matlab DSP16 years ago

Dear all, I've a problem demodulating in QPSK. My transmitter is a vector signal analyzer (VSG) and a labVIEW programme is used to capture...

Dear all, I've a problem demodulating in QPSK. My transmitter is a vector signal analyzer (VSG) and a labVIEW programme is used to capture the data. Matlab is used to despread the data using PN sequence of 1024 bits, after which the data is being demodulated. Below is a portion of the code using BPSK, % Read off Gain Factor and offset Gain_factor = fread(fid, 1, 'double'); Offset = frea...


Symbol Sync for QPSK !!

Started by abhishek agarwal in Matlab DSP18 years ago

Hi all, i trying to implement the QPSK mod and Demod in matlab. I'm not able to get the Symbol Sync for QPS based on Early and Late...

Hi all, i trying to implement the QPSK mod and Demod in matlab. I'm not able to get the Symbol Sync for QPS based on Early and Late Gate Integrators. Can one help me regarding this or forward me some material that can help me implement this in matlab. Thanks, Abhishek Abhishek Agarwal


creating BPSK, QPSK, DPSK modulated signals

Started by Jim Lee in Matlab DSP21 years ago

I need some help in creating BPSK, QPSK, DPSK modulated signals. If someone know the modem design by using the signals above, it...

I need some help in creating BPSK, QPSK, DPSK modulated signals. If someone know the modem design by using the signals above, it will be great help Thanks


Please help: BER for QPSK in OFDM over Rayleigh matlab code doesn't work.

Started by mazd...@gmail.com in Matlab DSP13 years ago

I try to implement the matlab code on BER for QPSK in OFDM over rayleigh channel (with n taps). However the result is a straight line. There must...

I try to implement the matlab code on BER for QPSK in OFDM over rayleigh channel (with n taps). However the result is a straight line. There must be something wrong in my code but I cannot figure it out what is wrong. Could you please help me to check it. I have to hand the work soon. Please please please help. Thank you very much. [QUOTE]clear; clc; N=64; % FFT size Nsd = 48; % Number of ...


SOVA for QPSK symbols.

Started by Karthik Iyer in Matlab DSP19 years ago

Hi All, I am new member of this group and I need a method to compute the soft decisions using SOVA for QPSK symbols. I am using a rate...

Hi All, I am new member of this group and I need a method to compute the soft decisions using SOVA for QPSK symbols. I am using a rate 1/2 systematic convolutional  code with following trellis structure:   trellis = poly2trellis ( 3, [5 7], 5 );   Please suggest me


Some pieces of Software

Started by Ramiro Pedros in Matlab DSP24 years ago

Hello, I just wanted to ask some help regarding digital communications. Could anyone send me any piece of information...

Hello, I just wanted to ask some help regarding digital communications. Could anyone send me any piece of information concerning how the non-linearities of certain devices (mixers, power amplifiers, ...) may affect the digital communication schemes (QPSK, ODFM, ...)? Do


QAM demapper

Started by r_i_k_k_a_r_d_o in Matlab DSP18 years ago 1 reply

Hi, is there anyone who can explain me how does it work the QAM demapper in the DVB demo of Simulink? Can you please give hints on how create a...

Hi, is there anyone who can explain me how does it work the QAM demapper in the DVB demo of Simulink? Can you please give hints on how create a demapper for 16 QAM and QPSK? Thanks a lot. Riccardo Calonaci


Newbie to OFDM

Started by Rohith Ramnath in Matlab DSP17 years ago 1 reply

Hello Everyone, I started working recently on OFDM. I am trying to use simulink to build a simple system with four sub-carriers. However, I...

Hello Everyone, I started working recently on OFDM. I am trying to use simulink to build a simple system with four sub-carriers. However, I am unable to comprehend the results I am getting. Here is what I am doing: 1. I am using a Bernoulli Binary data Generator 2. It's output is QPSK modulated. 3. After separating the real and complex parts I concatenate the matrix and zero pad it to...


Frequency divider

Started by sasilion in Matlab DSP22 years ago 2 replies

Hi Guys, My question has something to do with frequency multiplier and divider in a PLL. For example, before a QPSK is fed into...

Hi Guys, My question has something to do with frequency multiplier and divider in a PLL. For example, before a QPSK is fed into a PLL, i have to pass the signal through a 4th power device and bandpass it. I could do this by muliplying 4 times. However, i am not sure how to


bits to symbols and vice versa

Started by Toivon Sarastus in Matlab DSP22 years ago 2 replies

Hi, Is there some easy way to encode and decode QPSK symbols to bits? For exmple 0 -> 00, 1-> 10, 2 -> 01, 3 -> 11. I didn't...

Hi, Is there some easy way to encode and decode QPSK symbols to bits? For exmple 0 -> 00, 1-> 10, 2 -> 01, 3 -> 11. I didn't find any function that does that. Of course one can write a simple function with four if - clauses, but can you do it more elegantly?


SC-FDE

Started by sundar janaa in Matlab DSP19 years ago

Dear all, I am simulating Single Carrier Frequency Domain Equalizer in AWGN Channel.. I used the QPSK BER curve and modified that to make...

Dear all, I am simulating Single Carrier Frequency Domain Equalizer in AWGN Channel.. I used the QPSK BER curve and modified that to make the SC-FDE. I am using 512 fft size and guard interval of 56. As awgn channel is used ,there is no operation in between the fft & ifft at the receiver. Should I do the zero padding at the transmitter?. If anyone


OFDM Simulation

Started by sundar janaa in Matlab DSP19 years ago

Dear all, I have some problems regarding the simulation of OFDM Chain to obtain the BER curve...Pls help me ..it is very urgent. Great...

Dear all, I have some problems regarding the simulation of OFDM Chain to obtain the BER curve...Pls help me ..it is very urgent. Great helps are appreciated. 1). Noise Variance & Zero Padding...- in my understanding , we have to normalize the tranmited bits not the symbol when plotting the BER vs EbNo curve. Is that right?. After qpsk modulation .