发明名称 OFDM communications methods and apparatus
摘要 OFDM signal communication methods and apparatus are described. In accordance with the invention OFDM signals are generated in the time domain with symbols being mapped to specific points in time. Training symbols may be included in the transmitted OFDM signal to facilitate symbol recovery. An exemplary receiver of the invention receives the OFDM signal from the communications channel, converts it into the frequency domain, and then filters it in the frequency domain to eliminate tones corresponding to other users. The filtered signal free of MAC interference is then converted into the time domain where channel estimation and compensation operations are performed. After channel compensation symbol recovery is performed in the time domain.
申请公布号 US9426013(B2) 申请公布日期 2016.08.23
申请号 US201414278405 申请日期 2014.05.15
申请人 QUALCOMM Incorporated 发明人 Laroia Rajiv;Li Junyi
分类号 H04L27/26;H04L5/00;H04L5/02 主分类号 H04L27/26
代理机构 代理人 Dong Dalei
主权项 1. A method of generating a frequency division multiplexed signal at a communications device for transmission in a wireless communication system, comprising: obtaining, by the communications device, one or more sets of M complex data symbols for transmission using a set of M tones allocated to the communications device for a dwell period comprising a plurality of symbol periods, wherein the set of M tones is a subset of tones in an available bandwidth; generating, by the communications device, one or more sets of M signal coefficients based at least in part on the one or more sets of M complex data symbols, wherein the one or more sets of M signal coefficients are mapped to the set of M tones for one or more symbol periods of the plurality of symbol periods of the dwell period, wherein generating the one or more sets of M signal coefficients comprises generating each of the one or more sets of M signal coefficients by performing a summation of a product of a set of M complex data symbols of the one or more sets of M complex data symbols and M complex sinusoids corresponding to the set of M tones; mapping, by the communications device, at least one set of M training symbols to the set of M tones for at least one symbol period of the plurality of symbol periods of the dwell period; processing, for each symbol period of the plurality of symbol periods of the dwell period, a corresponding set of M mapped symbols of the one or more sets of M signal coefficients and the at least one set of M training symbols to obtain the frequency division multiplexed signal for the each symbol period of the plurality of symbol periods of the dwell period; and transmitting, by the communications device, the frequency division multiplexed signal in the wireless communication system.
地址 San Diego CA US