Note: You will need to download the file aotj1.wavfrom the course webpage. Although not absolutely necessary, it will help if you have earphones.
1. 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.
2. 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.
3. 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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