Question 1

In QAM,if you have eight possible amplitudes,how many bits can you send per clock cycle?&#10;A)3.&#10;B)6.&#10;C)8.&#10;D)16.&#10;E)None of the above.

Accepted Answer

In QAM, the number of possible amplitudes is represented as 2^n, where n is the number of bits that can be sent per clock cycle.

If there are 8 possible amplitudes, then 2^n = 8, which can be rewritten as 2^3 = 8.

Therefore, n = 3, meaning that 3 bits can be sent per clock cycle.

The answer is B, 6, as it is incorrect and not one of the options provided.

Question 2

QPSK represents ________ bits per clock cycle.&#10;A)1&#10;B)2&#10;C)4&#10;D)16

Accepted Answer

QPSK (Quadrature Phase Shift Keying) encodes 2 bits per symbol, allowing it to represent 2 bits per clock cycle.

Question 3

Phase modulation uses two loudness levels.

Accepted Answer

Phase modulation uses two phase states to encode information, not two loudness levels.

Question 4

In QAM,if you have four possible amplitudes,you have ________ possible states.&#10;A)4&#10;B)8&#10;C)16&#10;D)None of the above.

Accepted Answer

In QAM, the amplitude and phase of a carrier signal are modulated to transmit information. If we have four possible amplitudes, we can represent each of them using 2 bits (2^2=4). Similarly, if we have four possible phases, we can represent each of them using 2 bits (2^2=4). Therefore, we have a total of 4x4=16 possible states in QAM.

Question 5

QAM uses ________.&#10;A)amplitude modulation&#10;B)phase modulation&#10;C)Both A and B&#10;D)Neither A nor B

Accepted Answer

QAM (Quadrature Amplitude Modulation) uses both amplitude and phase modulation to transmit digital signals over a carrier wave. It is a combination of Amplitude Shift Keying (ASK) and Phase Shift Keying (PSK) methods. In QAM, both the amplitude and phase of the carrier signal are varied to represent the digital data being transmitted, which results in a higher data transfer rate than purely amplitude or phase modulation.

Question 6

In QAM,if you have eight possible amplitudes,you have ________ possible states.&#10;A)4&#10;B)8&#10;C)16&#10;D)64&#10;E)None of the above.

Accepted Answer

The answer of In QAM,if you have eight possible amplitudes,you...

Question 7

Frequency modulation uses two loudness levels.

Accepted Answer

Frequency modulation uses changes in frequency to convey information, not loudness levels.

Deck 13: More on Modulation