Patent ID: 9184821
Filing Date: 2015-11-10
Classification: H04B,H04L

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) determining, by an initial training performed between the first and second communication devices, at least one of four pluralities including a plurality of first transmitting-antenna-setting candidates for the first transmitting antenna, a plurality of first receiving-antenna-setting candidates for the first receiving antenna, a plurality of second transmitting-antenna-setting candidates for the second transmitting antenna, and a plurality of second receiving-antenna-setting candidates for the second receiving antenna; (b) determining, in the initial training and based on the at least one of four pluralities, at least one first antenna-setting pair for the first transmitting antenna and the second receiving antenna, and determining at least one second antenna-setting pair for the first receiving antenna and the second transmitting antenna; (c) initiating, after the initial training including the operations (a) and (b), radio communication between the first and second communication devices using one of the at least one first antenna-setting pair and one of the at least one second antenna-setting pair, and detecting disconnection of communication or deterioration in communication quality of the radio communication between the first and second communication devices; and (d) when the disconnection of communication or the deterioration in communication quality is detected, performing a link re-establishment training including at least one of following operations (d1), (d2), (d3) and (d4) without re-performing the initial training including the operations (a) and (b): (d1) transmitting a first training signal from the first transmitting antenna while switching antenna setting of the first transmitting antenna among at least some of the plurality of first transmitting-antenna-setting candidates, and receiving the first training signal by the second receiving antenna set with a fixed beam pattern; (d2) transmitting a second training signal from the second transmitting antenna while switching antenna setting of the second transmitting antenna among at least some of the plurality of second transmitting-antenna-setting candidates, and receiving the second training signal by the first receiving antenna set with a fixed beam pattern; (d3) transmitting a third training signal from the first transmitting antenna set with a fixed beam pattern, and receiving the third training signal by the second receiving antenna while switching antenna setting of the second receiving antenna among at least some of the plurality of second receiving-antenna-setting candidates; and (d4) transmitting a fourth training signal from the second transmitting antenna set with a fixed beam pattern, and receiving the fourth training signal by the first receiving antenna while switching antenna setting of the first receiving antenna among at least some of the plurality of first receiving-antenna-setting candidates.