ANTENNA DIVERSITY RECEIVING APPARATUS

PROBLEM TO BE SOLVED: To composite signals by taking into consideration the correlation of an interference component between antennas and to make a signal power-to- interference power ratio (SIR) maximum regarding an antenna diversity receiving apparatus, which performs a multipath composition in a mobile radio communication terminal device or the like using a spectral diffusion system. SOLUTION: The signals which are received by two antennas 1-1, 1-2 so as to be A/D-converted are back-diffused at each antenna by a back-diffusion part 1-4 for each path at the same back-diffusion timing decided by a searcher 1-3. A conversion-factor and weighting-factor generation part 1-5 calculates a conversion factor and a weighting factor on the basis of a channel estimation value by a back-diffused signal for channel estimation, in such a way that the correlation of the interference component between the antennas is eliminated. The conversion factor and the weighting factor are multiplied by the back- diffused signal so as to be converted or weighted and composited by a signal conversion and composition part 1-6, and a composited signal is output to a signal processing part 1-7.