Patent ID: 8050358

Claim:
A transmit diversity method of a mobile communication system for transmitting an input data symbol of length N using first and second transmission antennas, the method comprising: a) diversity encoding the input data symbol to generate first and second symbols for transmission from the first and second transmission antennas, respectively, and outputting the first symbol and the second symbols, wherein each of the first and second symbols have the same length N as the input data symbol; b) separating the first symbol into first and second groups of length N/2, and separating the second symbol into first and second groups of length N/2; c) generating an orthogonal code set of length N/2, and outputting first, second, third and fourth transmit symbols respectively generated by spreading each of the first and second groups of the first symbol and the first and second groups of the second symbol with the generated orthogonal code set; and d) mapping the first and the second transmit symbols to symbols in a frame of the frequency and time domains and transmitting the mapped first and second transmit symbols through the first transmission antenna, and mapping the third and the fourth transmit symbols to symbols in a frame of the frequency and time domains and transmitting the mapped third and fourth transmit symbols through the second transmission antenna.