Description
Note: You will need to download the file aotj1.wavfrom the course webpage. Although not absolutely necessary, it will help if you have earphones.
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Read the audio file aotj1.wav. From the signal, figure out the number of quantization levels (bits/sample) and the quantization levels (this is a uniformly quantized sound signal, with values between +1 and -1, i.e., Vp = 1). Convert this signal into a binary NRZ-L PCM signal x(t) of pulse width T = 1 secs, sampled at dt = 0.1 sec, with s1(t) = A, 0 t T and s2(t) = A, 0 t T. You might find the function dec2bin useful.
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Ignoring Inter-symbol interference, add zero-mean Gaussian noise with different vari-ances (as in the previous lab) to simulate channel noise. From this noi y signa , detect the transmitted bit stream using matched filters followed by the detection proc ss.
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Convert the detected bit stream back into the amplitude signal, and ee (listen) if the
audio signal is a faithful copy of the riginal audio signal using the soundfile.read function fromsoundfilelibrary, and sounddevicelibrary. Try this for various amounts of noise added.
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