Rate Modulation for Multiple Signal Transmission

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What is the main problem faced by several radio stations broadcasting audio baseband signals directly?

Lack of tunable bandpass filters

Inability to use modulation

Insufficient channel bandwidth

Interference between signals due to overlapping spectra (correct)

What is the purpose of modulation in frequency-division multiplexing (FDM)?

To digitize analog signals

To translate each signal to a different frequency range (correct)

To reduce noise in the channel

To increase the channel bandwidth

What is the primary advantage of frequency-division multiplexing (FDM) over direct broadcasting?

Improved signal-to-noise ratio

Efficient use of channel bandwidth by multiple signals (correct)

Reduced signal processing requirements

Increased channel bandwidth

What is the function of a tunable bandpass filter in a receiver using frequency-division multiplexing (FDM)?

To select the desired signal from multiple signals Signup and view all the answers

What is the name of the technique that shares the channel bandwidth by transmitting different signals at different time intervals?

Time-division multiplexing (TDM) Signup and view all the answers

What is the primary goal of modulation in digital communications?

To enable simultaneous transmission of multiple signals Signup and view all the answers

What is a major limitation of using baseband signals for transmission?

The signal wavelength is too long for reasonable antenna dimensions. Signup and view all the answers

What is the primary purpose of modulation in digital communications?

To facilitate transmission by translating the signal spectrum. Signup and view all the answers

Why is modulation necessary for the simultaneous transmission of several signals?

To avoid signal interference and overlap. Signup and view all the answers

What determines the wavelength of a signal?

The frequency of the signal. Signup and view all the answers

What is the primary advantage of using digital modulation over analog modulation?

Digital modulation is more resistant to noise and interference. Signup and view all the answers

What is the relationship between the wavelength of a signal and its antenna requirements?

A shorter wavelength requires a smaller antenna. Signup and view all the answers

What is the significance of Shannon’s result in communication systems?

It represents the upper limit on the rate of communication over a channel Signup and view all the answers

Why are practical communication systems unable to achieve the Shannon rate?

Due to the complexity and impracticality of achieving the Shannon rate Signup and view all the answers

What is the purpose of modulation in communication systems?

To modify the signal to facilitate transmission over a channel Signup and view all the answers

What is the process of reversing modulation called?

Demodulation Signup and view all the answers

What type of modulation varies the carrier amplitude in proportion to the baseband signal?

Amplitude Modulation (AM) Signup and view all the answers

What is the name of the high-frequency signal used in modulation?

Carrier signal Signup and view all the answers