Patent ID: 8971964
Filing Date: 2015-03-03
Classification: H01Q,H04B

Abstract:
1. A control method of a radio communication system comprising first and second communication devices, wherein the first communication device is configured to control a transmission beam direction of a first transmitting antenna by changing transmitting-antenna setting and to control a reception beam direction of a first receiving antenna by changing receiving-antenna setting, the second communication device is configured to control a transmission beam direction of a second transmitting antenna by changing transmitting-antenna setting and to control a reception beam direction of a second receiving antenna by changing receiving-antenna setting, and the method comprises: (a) transmitting a training signal from the first transmitting antenna while changing antenna setting of the first transmitting antenna; (b) receiving the training signal by the second receiving antenna in a state where a fixed beam pattern is set in the second receiving antenna; (c) obtaining a data string describing a relation between antenna setting of the first transmitting antenna and a reception signal characteristic of the second receiving antenna based on a reception result of the training signal obtained in the operation (b); (d) determining, by using the data string, at least one first transmitting-antenna-setting candidate, which each serves as a candidate to be used for communication, of the first transmitting antenna; (e) determining at least one second transmitting-antenna-setting candidate, which each serves as a candidate to be used for communication, of the second transmitting antenna, by performing the operations (a) to (d), which were performed by using the first transmitting antenna and the second receiving antenna, for a combination of the second transmitting antenna and the first receiving antenna; (f) transmitting a training signal from the first transmitting antenna in a state where a fixed beam pattern is set in the first transmitting antenna; (g) receiving the training signal by the second receiving antenna while changing antenna setting of the second receiving antenna; (h) obtaining a data string describing a relation between antenna setting and a reception signal characteristic of the second receiving antenna based on a reception result of a training signal obtained in the operation (g); (i) determining at least one second receiving-antenna-setting candidate, which each serves as a candidate to be used for communication, of the second receiving antenna by using the data string; (j) determining at least one first receiving-antenna-setting candidate, which each serves as a candidate to be used for communication, of the first receiving antenna, by performing the operations (f) to (i), which were performed by using the first transmitting antenna and the second receiving antenna, for a combination of the second transmitting antenna and the first receiving antenna; (k) measuring communication quality for all or some of combinations between the at least one first transmitting-antenna-setting candidate and the at least one second receiving-antenna-setting candidate, and for all or some of combinations between the at least one first receiving-antenna-setting candidate and the at least one second transmitting-antenna-setting candidate; (l) selecting a first combination having a highest communication quality from the all or some of combinations between the at least one first transmitting-antenna-setting candidate and the at least one second receiving-antenna-setting candidate; (m) selecting a second combination having a highest communication quality from the all or some of combinations between the at least one first receiving-antenna-setting candidate and the at least one second transmitting-antenna-setting candidate; (n) performing radio communication between the first and second communication devices by using the first combination and the second combination; and (o) when deterioration in communication quality is detected during the radio communication in the operation (n), performing the operations (a)-(m) again and performing radio communication by using a newly selected first combination and a newly selected second combination.