CHALLENGE You are now given a problem to test your knowledge of this chapter's objectives: Referring to the antenna azimuth position control system shown in Appendix A2, Configuration 2, do the following: a. Find the closed-loop transfer function using block diagram reduction. b. State Space SS Represent each subsystem with a signal-flow graph and find the state-space representation of the closed-loop system from the signal-flow graph. c. Use the signal-flow graph found in (b) along with Mason's rule to find the closed- loop transfer function. d. Replace the power amplifier with a transfer function of unity and evaluate the closed-loop percent overshoot, settling time, and peak time for K = 5. e. For the system used for (d), derive the expression for the closed-loop step response. f. For the simplified model in (d), find the value of preamplifier gain, K, to yield 15% overshoot. CONFIGURATION 2: HAS THE FOLLOWING VALUES Vp(s) 150 S+ 150 0.16 5(5+1.32) Power amp Motor and load 1,00 Ea(s) (s+100) 0.2083 s(s+1.71) (a) 0,(s) Vp(s) 20.83 (s+100 (s+1.71) wo(s) (b) Convert to angular velocity 31.245 (5+150) (5+1.32) S wo(s)

Q.2) A) Explain the nomenclature of additive white Gaussian noise (AWGN) What are the PSD and auto correlation of the AWGNE

Explain the RC time constant and what its value means in terms of circuit characteristics.

A discrete-spectrum baseband modulating signal has com- ponents at the following frequencies: 500 Hz, 1.5 kHz, 6-3

Is coupling a consequence of signal absorptions? What is the problem of this?

Formulate an appropriate signal-to-noise ratio for the seat belt experiment. Analyze the experimental data using this metric. Is signal-to-noise ratio a useful objective function in this case? Why or why not?

The figure below of signal flow graph shown has: 2 4 5 6 8 Select one: a. forward path = 5, loops = 3, and non-touching loops = 0 b. forward path = 3, loops = 3, and non-touching loops = 0 C. forward path = 3, loops = 4, and non-touching loopS = 2 d. forward path = 2, loops = 3, and non-touching loops = 0

A modem (modulator-demodulator) converts digital data to analog signal. There are 3 ways to modulate a digital signal on an analog carrier signal. How that ways will work when amplitude frequency carries 0 and 1. Describe all possible ways.

Q2 (A) A frequency modulator is supplied with a carrier at frequency fc = 5 MHz and an audio tone signal of Am = 1 volt amplitude and frequency fm = 1 kHz. It produces a frequency deviation f of 10 kHz as the output of the frequency modulator. (3)(i) The FM waveform described above is passed through a frequency multiplier with a total multiplication factor of 18, that is, fout = 18*fc. After passing through the frequency multiplier, what is the frequency deviation f at the output?(ii) The output of the multiplier in part (a) is next input to a mixer stage with the LO oscillator frequency set at fLO = 55 MHz. Find the sum-frequency output fo of the mixer’s IF port and also find the magnitude of the frequency deviation f.

What circuit compensates for the greater frequency deviation at the higher modulating signal frequencies?