Single Carrier FDMA: A New Air Interface for Long Term Evolution

Preface

Commercial cellular telecommunications date from the early 1980s when the first car telephone arrived on the market. Public acceptance grew rapidly and the technology progressed through a sequence of “generations” that begin with each new decade. The first generation systems in 1980 used frequency division multiple access (FDMA) to create physical channels. Digital transmission arrived in the early 1990s with the most popular systems employing time division multiple access (TDMA) and others relying on code division (CDMA). Third generation technology dating from 2000 uses code division whereas the next generation promises a return to frequency division. As the preferred form of multiple access migrates through the time-frequency-code space, the bandwidth of the transmission channels steadily increases. The first systems transmitted signals in 25 or 30 kHz bands. Second generation Global System for Mobile (GSM) uses 200 kHz and the CDMA channels occupy 1.25 MHz. The channel spacing of third generation wideband CDMA is 5 MHz and the next generation of cellular systems will transmit signals in bandwidths up to 20 MHz.

In 2008, two FDMA technologies are competing for future adoption by cellular operating companies. WiMAX, standardized by the IEEE (Institute of Electrical and Electronic Engineers), was first developed to provide broadband Internet access to stationary terminals and later enhanced for transmission to and from mobile devices. The other emerging technology, referred ...