3. Time Division Multiplexing (TDM), how does it work? Please draw diagram for illustration. How is it different from FDM?

3. Some GPS receivers use 1 bit ADCS (Analog-to-digital Converters) to sample and quantize the signal i.e. the output of the ADC is simply 2 quantization levels: -1 or +1. This is typically done to save on power. (a) What is the quantization SNR? How does it compare to typical thermal noise SNR of a GPS signal before correlating with the CDMA code? (b) Justify, how come it is possible to sample the signal using a single bit and still get good performance.

Pulse-code modulation (PCM) is the standard form of digital audio in computers, compact discs, digital telephony and other digital audio applications. Figure 3 shows the 3bit PCM system that transmit the 250 kHz analog signal with the voltage range from -6 mV to 6 mV. i) Identify the quantized value, voltage range and binary code for each level by building your own quantization table. ii) Calculate the minimum sampling rate and sampling time. ii) Identify the corresponding sampled voltage, the quantized voltage and binary code if the input signal is sampled at time t1 = 2us, t2 = 4us, t3 = 6us, t4 = 8µs. iv) Sketch the output in (iii) if it is fed to Manchester coding line encoder with bit rate of 20000 bit/sec and amplitude of +4 V. 5 4 3 2 10 Timel(usec) Figure 3 Amplitude (mV)

3. Which of the following is a key characteristic of orthogonal frequency-division multiplexing?A. Amplitude modulationB. Noise performanceC. Digital modulationD. Spectral efficiency

1.     Calculate the frequency of the TDM pulses for a 4 - channel TDM transmitter  if the maximum frequency of the analog input signal is 8kHz. Assume that the sampling frequency is equal to the Nyquist rate.                     What is FDM?       Compare TDM with FDM.

Consider time division multiplexing. Which of the following component(s) are involved in the modulator? (i) Mixer (ii) Bandpass filter (iii) Lowpass filter O a. (ii) only O b. None of the other options O c. d. (i) only (iii) only

can you help me at least up to paragraph 3 or 4, please?

Q3) Twenty voice signals are sampled uniformly and then time division multiplexed. The sampling operation uses flat samples with 2 us duration. The multiplexing operation provides for synchronization by adding an extra pulse of 2 us. the highest frequency component of each signal is 3.4 kHz. a. For sampling rate of 8 kHz, calculate spacing between successive pulses of multiplexed signal. b. For Nyquist rate, repeat part a.

Please assist with question 2 with details on how to do it. Thank you.  2. This problem addresses the digitization of a television signal using pulse-code  modulation. The signal bandwidth is 4.5 MHz. Specifications of the modulator include  the following: Sampling: 15% in excess of the Nyquist rate Quantization: uniform with 1024 levels Encoding: binary Determine (a) the Nyquist rate, and (b) the minimum permissible bit rate.

The image added shows a digital modulator.     State what the modulation scheme is and show how the modulated sequence 101 looks like if one bit contains three periods of the carrier sine wave, for the following types of modulating binary sequences: a) Unipolar   b) Bipolar