Radio base station apparatus

A radio base station apparatus comprising a shared transmission/reception apparatus configured to transmit and receive both a signal for a first mobile communication system and a signal for a second mobile communication system, wherein

• the shared transmission/reception apparatus comprises:
• a signal converter section configured to convert an inputted transmission baseband signal for the second mobile communication system from an optical signal to an electrical signal;
• a transmission/reception processor section for the second mobile communication system configured to perform frequency conversion processing on the transmission baseband signal for the second mobile communication system outputted from the signal converter section, and to output a transmission radio frequency signal for the second mobile communication system;
• a power level adjuster section configured to adjust a power level of a transmission radio frequency signal for the first mobile communication system inputted from a transmission/reception processor section for the first mobile communication system;
• a combiner section configured to generate a transmission radio frequency signal by combining the transmission radio frequency signal for the first mobile communication system outputted from the power level adjuster section and the transmission radio frequency signal for the second mobile communication system outputted from the transmission/reception processor section for the second mobile communication system;
• and
• a common amplifier section configured to amplify a power level of the transmission radio frequency signal outputted from the combiner section at a predetermined amplification rate, and to output the resultant signal, and
• the transmission/reception processor section for the first mobile communication system is not provided in the shared transmission/reception apparatus.