Help me write program that creates QPSK signal in Matlab

[tele]

Help QPSK

Give A={a1, a2, a3, a4}

**broken link removed**


- Write Matlab program creating sequence QPSK random signal {s} n=1,...N-1
s belong to A.
-generate signal s*p(t), p(t) is response of rise cosine. p(t) sampled faster than T of symbol: 10 . Write program illustrating sequence signal transmitting.

Please help me, I have just learnt Matlab.

Added after 5 hours 42 minutes:

Please help me!!

 

[mileoung]

Re: Help QPSK

MATLAB provides an excellent Help, just do a search there and most of your answers will be there!

len = 10000; % Number of symbols
M = 4; % Size of alphabet
msg = randint(len,1,M); % Original signal

% Modulate using PSK
txpsk = pskmod(msg,M);

nsamp = 11; % Oversampling rate

%% Filter Definition
% Define filter-related parameters.
filtorder = 40; % Filter order
delay = filtorder/(nsamp*2); % Group delay (# of input samples)
rolloff = 0.25; % Rolloff factor of filter

% Create a square root raised cosine filter.
rrcfilter = rcosine(1,nsamp,'fir/sqrt',rolloff,delay);

% Upsample and apply square root raised cosine filter.
ytx = rcosflt(txpsk,1,nsamp,'filter',rrcfilter);