Delay Spread Requirements for Wireless Networks in the 2 . 4 GHz and 5 GHz Bands

This paper starts with a brief overview of radio channel models. The most important parameter in these models is the delay spread, since this is directly related to the complexity of a modem. Various measurement results reported in the literature are summarized, showing that for most office buildings, the delay spread is the range of 40 to 70 ns, while larger delay spreads up to 300 ns can be expected in large buildings like shopping centers and factories.