Why is Time-bandwidth Product Important?

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Why is Time-bandwidth Product Important?

To calculate the period of a signal with finite bandwidth, Heisenberg’s uncertainty principle plays a vital role where the time-bandwidth product indicates the processing gain of the signal.

We apply spread spectrum techniques in wireless communication for various reasons, such as interference resilience, security, robustness in multipath, etc. But in spread spectrum techniques, we compromise some bandwidth.

The time-bandwidth product for Gaussian-shaped pulses is 0.44 (approx.).

If the time-bandwidth product of a signal is >> 1, then it indicates the usable bandwidth is very much greater than the data rate. So, in this case, we are unable to utilize the whole available bandwidth. For this case, spectrum efficiency will be less.

To your knowledge, the product of the variance of time and variance of bandwidth for a Gaussian signal is 0.25, and for a triangular-shaped signal, it is 0.3.

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Signal Processing

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