Patent ID: 9215698
Filing Date: 2015-12-15
Classification: H04L,H04W

Abstract:
1. A wireless communication system in which wireless communication between a base station and a communication terminal is carried out by use of a plurality of frequency bands, wherein: the plurality of frequency bands each include (i) a downlink sub-band that is a frequency band for use in downlink transmission from the base station to the communication terminal and (ii) an uplink sub-band that is a frequency band for use in uplink transmission from the communication terminal to the base station; the base station includes band allocation means that allocates, to the communication terminal, the downlink sub-band and the uplink sub-band in the plurality of frequency bands; the communication terminal includes quality measurement means that measures a communication quality of the downlink sub-band that has been allocated by the band allocation means of the base station; the base station includes communication control determination means that determines, in accordance with the communication quality of the downlink sub-band, communication control of the uplink sub-band that has been allocated by the band allocation means of the base station, the communication quality having been measured by the quality measurement means of the communication terminal, the uplink sub-band that has been allocated corresponding to the downlink sub-band that has been allocated; the communication terminal includes communication control means that controls, in accordance with the communication control of the uplink sub-band that has been allocated, the uplink transmission in the uplink sub-band that has been allocated, the communication control having been determined by the communication control determination means of the base station; and in a case where there exists a frequency band that includes (i) the uplink sub-band having been allocated to the communication terminal by the band allocation means of the base station but (ii) no downlink sub-band that has been allocated to the communication terminal by the band allocation means of the base station, the quality measurement means of the communication terminal further measures a communication quality of a downlink sub-band of another base station that is different from the base station; and the communication control determination means of the base station determines whether or not to carry out a handover of the uplink sub-band corresponding to the downlink sub-band, based on a comparison between (a) the communication quality of the downlink sub-band of the base station and (b) the communication quality of the downlink sub-band of the another base station, the communication qualities having been measured by the quality measurement means of the communication terminal.