Delay Spread
The received radio signal from a transmitter consists of typically a direct signal, plus
reflections of object such as buildings, mountings, and other structures. The reflected
signals arrive at a later time than the direct signal because of the extra path length,
giving rise to a slightly different arrival time of the transmitted pulse, thus spreading the
received energy. Delay spread is the time spread between the arrival of the first and
last multipath signal seen by the receiver.
In a digital system, the delay spread can lead to inter-symbol interference. This is due to
the delayed multipath signal overlapping with the following symbols. This can cause
significant errors in high bit rate systems, especially when using time division