Patent · US Expired

Orthogonal frequency division multiplexing transmit diversity system for frequency-selective fading channels

US7020072B1 · kind B1 · utility

141Cited by
7References
60Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 9, 2000
Grant dateMar 28, 2006
Priority date
Expiry dateMay 9, 2020

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L27/2626
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Wireless communications for frequency-selective fading channels is realized by employing a system including orthogonal frequency division multiplexing (OFDM) in combination with an at least two antenna transmit diversity arrangement. Specifically, OFDM converts a multipath channel into a plurality of narrowband subchannels each having flat fading. Then, the signals on the same frequency subchannels of the at least two antennas are grouped together. Considering a first frequency subchannel, during a first OFDM time interval, a first signal and a second signal are transmitted on the first frequency subchannel from a first antenna (0) and from a second antenna (1), respectively. During a second OFDM time interval, a reverse sign (−) complex conjugate of the second signal and a complex conjugate of the first signal are transmitted from the first antenna and the second antenna, respectively. In a specific embodiment of the invention, reduced complexity in the implementation is realized by a reverse order complex conjugate and a reverse order, reverse sign (−) complex conjugate and judicious selection of the processed data signals in order to transmit the appropriate ones of the signals …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.