Ultra wide band (UWB) technology

Short-range communication systems (known as wireless personal area network [WPAN] systems) with ranges of up to 10 m are becoming popular for replacing cables and enabling new consumer applications. However, systems such as Bluetooth and Zigbee, which operate in the 2.4 GHz ISM band, have a limited data rate, typically about 1 Mbps, which is insufficient for many applications, such as fast transfer of large files (e.g., wireless USB) and high-quality video streaming. To increase the data rate to several hundreds of Mbps, a higher bandwidth is preferred over a larger signal-to-noise ratio (SNR). This became possible when the FCC released frequency spectrum for ultra wide band (UWB) in the United States spanning from 3.1 to 10.6 GHz with an average transmit power level of only -41.3 dBm/MHz [1]. Since then, several proposals have been presented to realize a shortrange high data rate communication link. At present, both direct-sequence impulse communication and multiband orthogonal frequency division multiplexing (MB-OFDM) UWB systems are under consideration as a standard within the IEEE under IEEE802.15.3a. Industry has adopted MBOFDM UWB for high data rates as the ECMA-368 standard [2].