Virtual Labs

Which of the following best describes the trade-off between diversity and spatial multiplexing in MIMO?

a: Both increase simultaneously with more antennas Explanation

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b: Maximizing one usually reduces the other Explanation

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c: They are independent of each other Explanation

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d: Diversity is only used when multiplexing fails Explanation

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The Diversity-Multiplexing Tradeoff (DMT) illustrates the relationship between:

a: Number of antennas and total power Explanation

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b: Error rate and delay Explanation

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c: Data rate and reliability Explanation

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d: Bandwidth and frequency Explanation

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Which of the following correctly explains the diversity-multiplexing tradeoff at high SNR?

a: It disappears at high SNR Explanation

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b: Increasing diversity gain always increases multiplexing gain Explanation

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c: There exists a fundamental tradeoff between the two, even at high SNR Explanation

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d: Multiplexing gain is always better than diversity gain Explanation

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In practice, how is the trade-off between multiplexing and diversity typically handled?

a: By using only diversity in all situations Explanation

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b: Fixed hardware design with no flexibility Explanation

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c: Adaptive MIMO modes based on channel conditions Explanation

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d: Ignoring the channel and using default MIMO setting Explanation

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Which of the following MIMO techniques best exemplifies the multiplexing gain?

a: Alamouti scheme Explanation

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b: STBC with orthogonal coding Explanation

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c: V-BLAST Explanation

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d: Maximal ratio combining Explanation

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The maximum diversity gain in an N_t × N_r MIMO system is:

a: N_t Explanation

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b: N_r Explanation

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c: min(N_t, N_r) Explanation

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d: N_t × N_r Explanation

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What happens to the number of SISO channels when antennas are grouped for diversity?

a: It increases Explanation

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b: It remains the same Explanation

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c: It decreases Explanation

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d: It becomes zero Explanation

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If the maximum achievable diversity gain is 28, but the diversity gain achieved is 10 and the multiplexing gain is 2, find the number of transmit and receive antennas.

a: 7, 4 Explanation

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b: 6, 6 Explanation

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c: 14, 2 Explanation

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d: 8, 3 Explanation

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Multiplexing vs. Diversity