Communication system including relay station and data frame for the communication system

A relay station comprising:

• a first transmission and reception module configured to, in a first uplink relay sub-frame among uplink sub-frames, simultaneously transmit an uplink relay signal to a base station together with selected relay stations among a plurality of relay stations in response to the relay station being one of the relay stations selected by the base station,
• wherein the selected relay stations are selected based on whether the selected relay stations are capable of simultaneously performing reception from among the plurality of relay stations based on a channel information with respect to channels formed between the plurality of relay stations and the base station;
• and
• a second transmission and reception module configured to, in a second uplink relay sub-frame among uplink sub-frames, transmit an uplink relay signal to the base station using a scheduled radio resource, in response to the relay station being one of the remaining relay stations among the plurality of relay stations,
• wherein the relay station and the remaining relay stations sequentially transmit relay signals in the second uplink relay sub-frame using the scheduled radio resource.

An operational method of a base station, the method comprising:

• receiving, from a plurality of relay stations, channel information with respect to channels formed between the plurality of relay stations and a base station;
• selecting relay stations from among the plurality of relay stations based on the channel information;
• transmitting, in a first downlink relay sub-frame among downlink sub-frames, downlink relay signals simultaneously to the selected relay stations;
• and
• sequentially transmitting, in a second downlink relay sub-frame among downlink sub-frames, remaining downlink relay signals to the remaining relay stations using a scheduled radio resource,
• wherein the selected relay stations are selected based on whether the selected relay stations are capable of simultaneously performing reception from among the plurality of relay stations based on the channel information.

An operational method of a relay station, the method comprising:

• transmitting, in a first uplink relay sub-frame among uplink sub-frames, uplink relay signals simultaneously to a base station together with selected relay stations among a plurality of relay stations, in response to the relay station being one of the selected relay stations selected by the base station,
• wherein the selected relay stations are selected based on whether the selected relay stations are capable of simultaneously performing reception from among the plurality of relay stations based on a channel information with respect to channels formed between the plurality of relay stations and the base station;
• and
• transmitting, in a second uplink relay sub-frame among uplink sub-frames, an uplink relay signal to the base station using a radio resource scheduled by the base station, in response to the relay station being one of the remaining relay stations among the plurality of relay stations,
• wherein the relay station and the remaining relay stations sequentially transmit relay signals in the second uplink relay sub-frame using the scheduled radio resource.

A non-transitory computer-readable storage medium storing a program to implement an operational method of a base station, comprising instructions to cause a computer to:

• receive, from a plurality of relay stations, channel information with respect to channels formed between the plurality of relay stations and a base station;
• select relay stations from among the plurality of relay stations based on the channel information;
• transmit, in a first downlink relay sub-frame among downlink sub-frames, downlink relay signals simultaneously to the selected relay stations;
• and
• sequentially transmit, in a second downlink relay sub-frame among downlink sub-frames, remaining downlink relay signals to the remaining relay stations using a scheduled radio resource,
• wherein the selected relay stations are selected based on whether the selected relay stations are capable of simultaneously performing reception from among the plurality of relay stations based on the channel information.

A base station comprising:

• a channel information reception module configured to receive, from k relay stations, channel information with respect to channels formed between the plurality of relay stations and the base station;
• a selection module configured to select n relay stations, of the plurality of relay stations in which 1<n<k, that are capable, as determined from the channel information, of simultaneously receiving a transmission from the base station;
• and
• a transmission and reception module configured to transmit downlink relay signals simultaneously to the selected n relay stations while excluding k−n relay stations that are not selected,
• wherein the transmission and reception module is configured to transmit first downlink relay signals simultaneously to the selected relay stations in one portion of a downlink relay sub-frame, and to sequentially transmit second downlink relay signals to each of the k−n non-selected relay stations through a scheduled resource of another portion of the downlink relay sub-frame.

A base station comprising:

• a channel information reception module configured to receive, from a plurality of relay stations, channel information with respect to channels formed between the plurality of relay stations and the base station;
• a selection module configured to select relay stations from among the plurality of relay stations based on the channel information;
• a transmission module configured to, in a first downlink relay sub-frame among downlink sub-frames, transmit downlink relay signals simultaneously to the selected relay stations and, in a second downlink relay sub-frame among downlink sub-frames, sequentially transmit remaining downlink relay signals to the remaining relay stations using a scheduled radio resource,
• wherein the selection module is configured to determine relay stations that are capable of simultaneously performing reception to select relay stations from among the plurality of relay stations based on the channel information.