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A signal has a spectrum from 0 to 145 Hz, as shown below. It is sampled at a rate of 295 Hz. Find the region of the baseband spectrum that will become corrupted and unrecoverable even if an ideal "brickwall" filter is used for recovery.

Please give answer with explaination. Its quiz que (Points : 5) None; all will be recoverable
15–145 Hz
90–145 Hz
135–145 Hz

2 Answers

3 votes

Answer:

95

Step-by-step explanation:

User Anton Harniakou
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7 votes

Answer: None; all will be recoverable

Step-by-step explanation:

If a signal (band-limited) is sampled at regular intervals, it could be recoverable or not, based on the number of samples taken.

Let's assume that we want to take samples of a simple sinusoid; If we take more than two samples during a signal cycle, the original waveform will be able to be reconstructed, just passing the sampled waveform through a low-pass filter.

In the more general case in which the signal occupies a frequency spectrum, if the sample frequency is greater than the double of the highest frequency in the spectrum, the signal can be retrieved completely, according to the Nyquist Theorem.

In this case , as the highest frequency is 145 Hz, it would be enough to take samples at a rate greater than 290 Hz; As the sample rate is 295 Hz, all the signal can be recovered, at least, using an ideal "brickwall" low-pass filter.

User Giozh
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