(i) Create a MATLAB Simulink model to implement the following modulation system.

y(t) = (1+mx(t)) . cos(32000.pi.t)

Hint: after you read the required 10000 data samples, normalize it to between -1 and +1; i.e. xn(t) <--- x(t)/max(abs(x(t))

and use the command resample in Matlab to downsample the signal to 8000 samples/sec.

Provide a graph of the down-sampled signal segment you used, the Simulink simulation schematic, and the output y(t) for m = 0.3 and 0.9. What type of modulation is this? (ii) Use a random binary source generator (such as Bernoulli) in Simulink to replace (1 + m x(t)) in the above equation with a binary signal varying between 0 and 1. Provide the input signal, Simulink schematic, and output. Which type of modulation is this?

(iii) For x(t), original 10000 samples of speech, use (a) linear and (b) suitable mew-law nonlinear 4- bit quantizers and calculate to quantization error for both quantizers. Explain the differences and show the quantized waveforms.