Radio relay station, radio relay method, radio communication system, location management device, radio terminal, and radio communication method
Provided is a radio relay station which relays data transmitted and received by a radio base station a radio terminal in a radio communication system which employs the TDD scheme. The radio relay station receives data from the radio base station during a downlink subframe period and transmits data to the radio base station during an uplink subframe period. The radio relay station sets a remote side transmission period for transmitting data to the radio terminal in the uplink subframe period and sets a remote side reception period for receiving data from the radio terminal in the downlink subframe period.
1. A radio relay station configured to relay data between a first radio communication device and a second radio communication device, wherein the data is communicated using communication time frames segmented on a time axis, wherein each communication time frame comprises a first period and a second period, and wherein the radio relay station comprises:
a first transceiver configured to receive data from the first radio communication device in a first period of a first communication time frame and to transmit data to the first radio communication device in a second period of the first communication time frame, wherein a time length of the first period is longer than a time length of the second period;
a second transceiver configured to transmit data to the second radio communication device and to receive data from the second radio communication device; and
a controller configured to control the second transceiver,
wherein the controller sets a transmission period that comprises the second period of the first communication time frame and a first portion of a first period of a second communication time frame that is subsequent to the first communication time frame,
wherein, during the transmission period, the second transceiver transmits data to the second radio communication device in the second period of the first communication time frame, and
wherein the controller prevents transmission of data from the second transceiver to the second radio communication device during the first portion of the first period of the second communication time frame.
2. The radio relay station according to claim 1 , wherein the controller sets a reception period that comprises a second portion of the first period of the second communication time frame, and wherein, during the reception period, the second transceiver receives data from the second radio communication device.
3. The radio relay station according to claim 1 , wherein a frequency band available for radio communication by the first transceiver and the second transceiver is divided into at least three communication frequencies,
the three communication frequencies include a first communication frequency, a second communication frequency, and a third communication frequency between the first communication frequency and the second communication frequency,
the first transceiver performs radio communication with the first radio communication device by not using the third communication frequency but using the first communication frequency, and
the second transceiver performs radio communication with the second radio communication device by not using the third communication frequency but using the second communication frequency.
4. The radio relay station according to claim 1 , wherein the first radio communication device is a radio base station, and the second radio communication device is a radio terminal.
5. A radio relay method used for a radio relay station configured to relay data between a first radio communication device and a second radio communication device, wherein the data is communicated using communication time frames segmented on a time axis, and wherein each communication time frame comprises a first period and a second period, the radio relay method comprising:
causing a first transceiver to receive data from the first radio communication device in a first period of a first communication time frame and to transmit data to the first radio communication device in a second period of the first communication time frame, wherein a time length of the first period is longer than a time length of the second period; and
controlling a second transceiver configured to transmit data to the second radio communication device and to receive data from the second radio communication device, wherein the controlling comprises
setting a transmission period that comprises the second period of the first communication time frame and a first portion of a first period of a second communication time frame that is subsequent to the first communication time frame,
during the transmission period, causing the second transceiver to transmit data to the second radio communication device in the second period of the first communication time frame, and
preventing transmission of data from the second transceiver to the second radio communication device during the first portion of the first period of the second communication time frame.