RADIO TRANSMISSION METHOD AND RADIO TRANSMITTER

摘要

PROBLEM TO BE SOLVED: To perform the processing of base-band modulation and vector multiplication in a circuit not using a complex computing element and to reduce a circuit scale, a computing amount and power consumption by adding a signal point mapping processing through a complex weight coefficient for transmission directivity control to transmission data signals. SOLUTION: Components I of transmission signal D and Q versus signal point mapping relation formula are prepared in advance. Signal point mapping circuits 101 and 102 map a transmission information series at the time of modulation by using the complex weight coefficients W1 and W2 supplied for respective antennas A and B in a two-dimensional space indicated by an amplitude and a phase. RF circuits 103 and 104 are provided in the output stage of the signal point mapping circuits 101 and 102 and transmission signals for which the amplitude and phase of the same transmission signals D are changed, so as to provide transmission directivity are radio-transmitted from the antennas A and B. Thus, by signal point mapping the transmission signals D by using the complex weight coefficients W1 and W2 , a complex weighting processing is performed with a simple circuit.