Compute Power Delay Profile (PDP) from Delay Spread

1. How is maximum delay spread calculated?
2. Which information can be extracted from power delay profile?
3. What is meant by delay spread?
4. What is the effect of delay spread in signal propagation?

How is maximum delay spread calculated?

In other words, the maximum excess delay is defined as t_x - t₀. where t₀ is the first arriving signal and t_x is the maximum delay at which a multipath component is within X dB of the strongest arriving multipath signal (which does not necessarily arrive at t₀).

Which information can be extracted from power delay profile?

The power delay profile (PDP) gives the intensity of a signal received through a multipath channel as a function of time delay. The time delay is the difference in travel time between multipath arrivals. The abscissa is in units of time and the ordinate is usually in decibels.

What is meant by delay spread?

Delay spread is a measure of the multipath profile of a mobile communications channel. It is generally defined as the difference between the time of arrival of the earliest component (e.g., the line-of-sight wave if there exists) and the time of arrival of the latest multipath component.

What is the effect of delay spread in signal propagation?

In the case of frequency selective fading, the delay spread exceeds the symbol duration. On the other hand, when there is no dispersion and delay spread is less than the symbol duration, the fading will be flat, thereby affecting all frequencies in the signal equally.