ehbas
Newbie level 4
Hi
I want to simulate a new modulation scheme named DCSK for Differential Chaos Shift Keying.
this modulation does not use sinusoidal signals as base signals, but uses chaotic signals (a noise-like signal).
for each symbol to be sent, we have a signal consisted of N real samples. I want to pass this signals through a fading channel and I want to use rayleighchan function of MATLAB.
I have already simulated the scheme with my own code, the results are correct. but I should do it with MATLAB functions tow.
the code I had developed for the channel is:
note that x, n and r are real vectors of size N.
the main question is how can I model the channel for this modulation scheme using these MATLAB functions:
chann = rayleighchan(...);
r = filter(chann, x);
for modulation schemes like PSK, QAM, etc for each symbol is represented by a complex number. thus to simulate the fading channel one should write this code
note that the difference bitween PSK and my modulation is that I have a vector of N real samples for each symbol, but in PSK there is just one complex sample for each symbol.
in the above code, dpskSig is a 50000 size vector for 50000 consequent symbol.
I hope I could have explained my problem
tnx a lot
I want to simulate a new modulation scheme named DCSK for Differential Chaos Shift Keying.
this modulation does not use sinusoidal signals as base signals, but uses chaotic signals (a noise-like signal).
for each symbol to be sent, we have a signal consisted of N real samples. I want to pass this signals through a fading channel and I want to use rayleighchan function of MATLAB.
I have already simulated the scheme with my own code, the results are correct. but I should do it with MATLAB functions tow.
the code I had developed for the channel is:
Code:
alpha = random('rayleigh', 1/sqrt(2) );
n = sigma .* randn(1, N);
r = (alpha *. x) + n;note that x, n and r are real vectors of size N.
the main question is how can I model the channel for this modulation scheme using these MATLAB functions:
chann = rayleighchan(...);
r = filter(chann, x);
for modulation schemes like PSK, QAM, etc for each symbol is represented by a complex number. thus to simulate the fading channel one should write this code
Code:
% Create Rayleigh fading channel object.
chan = rayleighchan(1/10000,100);
% Generate data and apply fading channel.
M = 2; % DBPSK modulation order
hMod = comm.DBPSKModulator; % Create a DPSK modulator
hDemod = comm.DBPSKDemodulator; % Create a DPSK demodulator
tx = randi([0 M-1],50000,1); % Generate a random bit stream
dpskSig = step(hMod, tx); % DPSK modulate the signal
fadedSig = filter(chan,dpskSig); % Apply the channel effectsnote that the difference bitween PSK and my modulation is that I have a vector of N real samples for each symbol, but in PSK there is just one complex sample for each symbol.
in the above code, dpskSig is a 50000 size vector for 50000 consequent symbol.
I hope I could have explained my problem
tnx a lot
