Multi-antenna system using adaptive beamforming

PURPOSE: A multi antenna system using adaptive beamforming is provided to find a corresponding beamforming weight vector in a code book, thereby adjusting a phase of an RF signal. CONSTITUTION: A frequency down converter(300) down-converts a signal received from a signal combining unit to a baseband signal. An A/D converter(400) converts the baseband signal from the frequency down converter into a digital signal. When the receiving SNR(Signal to Noise Ratio) of the digital signal from the A/D converter is lower than a preset SNR, a beamforming controller(500) sets a currently set weight vector as another predetermined weight vector. The beamforming controller provides the set weight vector to a phase adjusting unit.