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CDMA RAKE Receiver Simulation MATLAB.....Channel Impulse Response.....??

Started by c.saagar August 26, 2008
Hello everyone,
 
I am a noob in DSP n in MATLAB. Well i hv been workin on the simulation of
Rake Receiver using MATLAB. What I have done so far is this:

1. Generated an input random sequence of 8 bits.
This input sequence simulates the information signal to be sent to the    
 channel for retrieving by the RAKE receiver.

>> input_bit = fix(2*rand(1,8)); >>input_bit_polar = (2*input_bit - 1); % input signal in antipodal form
2. Created a 32 bit PN sequence n 8 x 8 Walsh Code matrix.
>> W1 = [0];
W2 = [W1 W1; W1 W1]; W4 = [W2 W2; W2 W2]; W8 = [W4 W4; W4 W4]; The Walsh code sequence needs to be separated into the I and Q-channel for QPSK modulation.
>> Wodd = Wcode(1:2:length(Wcode)); % Walsh code for I-channel
Weven = Wcode(2:2:length(Wcode)); % Walsh code for Q-channel 3. I hv exored the PN sequence with a certain Walsh matrix row say Row2.
>> PNseq_I = fix(2*rand(1,length(bit_stream)*4)); % PN sequence for the
I-channel PNseq_Q = fix(2*rand(1,length(bit_stream)*4)); % PN sequence for the Q-channel 4. Then then i obtained a complex baseband in the end in the form real + imag*j Now i want to generate a channel impulse response which is fading (multipath) channel so that i can convolve it with this complex baseband signal. SO How should i generate it??? And what sort of channel estimation technique should I use for the same? Eagerly Waiting for ur reply..... Best Regards, Saagar...
On Aug 26, 8:51&#4294967295;am, "c.saagar" <c.saa...@gmail.com> wrote:
> > Now i want to generate a channel impulse response which is fading > (multipath) channel so that i can convolve it with this complex baseband > signal. SO How should i generate &#4294967295;it???
What kind of channel do you want to simulate? Indoor? Outdoor? Mobile? What carrier frequency, what environment?