Patent ID: 8724443

Claim:
A method of signal generation and transmission for a base station in a multi-cell orthogonal frequency division multiple access (OFDMA) wireless system having a plurality of base stations in a plurality of cells, the method comprising: generating orthogonal frequency division multiplexing (OFDM) symbols in a plurality of subframes by: scrambling frequency-domain data before modulation; modulating the scrambled data to produce modulated data symbols; generating training symbols; mapping the modulated data symbols to frequency-domain data subcarriers and the training symbols to frequency-domain pilot subcarriers; and converting the frequency-domain data subcarriers and frequency-domain pilot subcarriers to time-domain signals; controlling a configuration of the training symbols used to generate the OFDM symbols differently between subframes based on characteristics of each subframe, wherein: in a first type of subframe, the configuration of the training symbols is different among individual cells in the wireless system and based on a cell identity of each cell to facilitate unicasting; and in a second type of subframe, the configuration of the training symbols is the same for multiple cells in the wireless system to facilitate broadcasting; and transmitting the plurality of OFDM symbols.