Wireless communication system, relay apparatus and wireless communication method

A mobile relay device comprising:

• an antenna configured to receive a radio signal with a predetermined band including a desired frequency band associated with a communication device;
• a measurer configured to measure a signal level of an analog signal corresponding to the received radio signal in the predetermined band;
• a first outputter configured to amplify an amplitude of the input analog signal and extract the analog signal with the desired frequency band from the analog signal with the amplified amplitude when the analog signal corresponding to the received radio signal is input;
• a second outputter configured to extract the analog signal with the desired frequency band from the input analog signal and amplify an amplitude of the extracted analog signal when the analog signal corresponding to the received radio signal is input;
• and
• a switching controller configured to input the analog signal corresponding to the received radio signal to the first outputter when a signal level of the analog signal other than the desired frequency band in the predetermined band is less than a threshold, and to input the analog signal corresponding to the received radio signal to the second outputter when the signal level of the analog signal other than the desired frequency band in the predetermined band is equal to or greater than the threshold.

A wireless communication method executed by a wireless communication system including a first communication device, a second communication device, and a mobile relay device, the method comprising:

• an antenna for receiving a first radio signal with a predetermined band including a desired frequency band associated with the first communication device;
• measuring a signal level of an analog signal corresponding to the received first radio signal in the predetermined band;
• amplifying an amplitude of the input analog signal and extracting the analog signal with the desired frequency band from the analog signal with the amplified amplitude when the analog signal corresponding to the received first radio signal is input;
• extracting the analog signal with the desired frequency band from the input analog signal and amplifying the amplitude of the extracted analog signal when the analog signal corresponding to the received first radio signal is input;
• inputting the analog signal corresponding to the received first radio signal to a first outputter preforming a first output step when a signal level of the analog signal other than the desired frequency band in the predetermined band is less than a threshold, and inputting the analog signal corresponding to the received first radio signal to a second outputter performing a second output step when the signal level of the analog signal other than the desired frequency band in the predetermined band is equal to or greater than the threshold;
• and
• transmitting a second radio signal corresponding to the analog signal extracted by the first outputter or a third radio signal corresponding to the analog signal with the amplitude amplified by the second outputter to the second communication device.