Diversity transmission modes for MIMO OFMD communication systems

摘要

Techniques for transmitting data using a number of diversity transmission modes to improve reliability. At a transmitter, for each of one or more data streams, a particular diversity transmission mode is selected for use from among a number of possible transmission modes. These transmission modes may include a frequency diversity transmission mode, a Walsh diversity transmission mode, a space time transmit diversity (STTD) transmission mode, and a Walsh-STTD transmission mode. Each diversity transmission mode redundantly transmits data over time, frequency, space, or a combination thereof. Each data stream is coded and modulated to provide modulation symbols, which are further processed based on the selected diversity transmission mode to provide transmit symbols.; For OFDM, the transmit symbols for all data streams are further OFDM modulated to provide a stream of transmission symbols for each transmit antenna used for data transmission.