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We need to send 265 kbps over a noiseless channel with a bandwidth of 20 kHz. How many signal levels do we need?

We need to send 265 kbps over a noiseless channel with a bandwidth of 20 kHz. How many signal levels do we need? Correct Answer 128

256000 = 2 × 20000 × log L = 6.625. L = 98.7 Levels. Since this result is not a power of 2, we need to either increase the number of levels or reduce the bit rate. If we have 128 levels, the bit rate is 280 kbps.

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