The Advanced Mobile Phone System (AMPS) uses two bands. The first band of 824 to 849 MHz is used for sending, and 869 to 894 MHz is used for receiving. Each user has a bandwidth of 30 kHz in each direction. The 3-kHz voice is modulated using FM, creating 30 kHz of the modulated signal. How many people can use their cell phones simultaneously? Take note that 42 channels are used for control.
Ref to Example 6 in Lecture notes, Calculate the bandwidth of the multiplexed signal y(t) in the figure when the bandwidth of each input signal is equal to 400 MHz, the carrier frequency of the first channel is 1GHz and the guard bands are equal to 10 MHz. Give your answer in MHz.
Five channels, each with a 100-kHz bandwidth, are to be multiplexed together. What is the minimum bandwidth of the link if there is a need for a guard band of 10 kHz between the channels to prevent interference? Give your answer in kHz.
We need to transmit 100 digitized voice channels using a passband channel of 20 kHz. What is the bandwidth efficiency (bits/Hz) if we use no guard band? Take note that each digitized voice channel has a data rate of 64 Kbps.
Ref to Synchronous TDM Example 3 in Lecture notes, what is the bandwidth of the output signal at position A? Note that the factor d (r in Figure) for 16-ASK is given as 0.5. Give your answer in Hz.
Assume that a voice channel occupies a bandwidth of 4 kHz. We need to multiplex 10 voice channels with guard bands of 500 Hz using FDM. Calculate the required bandwidth. Give your answer in kHz.
A multiplexer combines four 100-kbps channels using a time slot of 2 bits. What is the frame rate? Give your answer in frame per second.
Four channels are multiplexed using TDM. If each channel sends 100 bytes/s and we multiplex 1 byte per channel, compute the bit rate for the link. Give your answer in bps.
Ref to Synchronous TDM Example 2 in Lecture notes, what is the output frame rate? Give your answer in frames per second.
Ref to Example 6 in Lecture notes, Calculate the bandwidth of the multiplexed signal y(t) in the figure when the bandwidth of each input signal is equal to 400 MHz, the carrier frequency of the first channel is 1GHz and guard bands are equal to 10 MHz. determine the carrier frequencies of the 2nd channel. Give your answer in MHz.
Choose the name of the multiplexing scheme for Example 6 (page 17) in the Lecture notes.
Ref to Synchronous TDM Example 2 in Lecture notes, what is the output bit rate? Give your answer in Mbps.
Ref to Synchronous TDM Example 3 in Lecture notes, what is the data rate of the link (before 16-ASK)? Give your answer in bps.
Ref to Synchronous TDM Example 3 in Lecture notes, what is the data rate of the link (before 16-ASK) if the sampling frequency is 250 Hz? Give your answer in bps.
A multiplexer combines four 100-kbps channels using a time slot of 2 bits. What is the bit rate? Give your answer in kbps.