Patent ID: 8515477

Claim:
A base station including: an estimation section that estimates a transmission condition of each frequency channel among a plurality of frequency channels to be used for communication; a reception section that receives a data signal which has been transmitted from each of a plurality of communication terminals through any frequency channel among the plurality of frequency channels; a measurement section that measures a received signal power of the received data signal for each of the communication terminals; a determination section that determines, for each of the communication terminals, whether or not the received data signal has been demodulated without error; and a control section that (i) assigns data slots times as data retransmission times to communication terminals, of the plurality of communication terminals, of which the received data signals are determined as not having been demodulated without error by the determination section, in such a manner that an earlier data slot time, among data slot times present in a repetitive manner, is assigned preferentially to a communication terminal, of the communication terminals having the data slot times assigned thereto, having a larger received signal power detected by the measurement section, and (ii) transmits a retransmission request signal that requests the communication terminal having the larger received signal power to retransmit the data signal at the data retransmission time assigned to the communication terminal having the larger received signal power, wherein, when assigning a same data retransmission time to two or more of the plurality of communication terminals, the control section assigns frequency channels, estimated as being in good transmission condition by the estimation section, to the two or more of the communication terminals in such a manner that a frequency channel, of the frequency channels estimated as being in good transmission condition, being in a better transmission condition is assigned preferentially to the communication terminal having the larger received signal power detected by the measurement section.