Communication system, control method, and communication control device
A wireless communication system includes: a communication control device; and a plurality of wireless base station devices capable of forming a plurality of beams and transmitting signals, the communication control device including: an estimation unit configured to estimate whether or not a range of a first beam emitted by a first wireless base station device among the plurality of wireless base station devices is correlated with a range of a second beam emitted by a second wireless base station device different from the first wireless base station device; and a use prohibition unit configured to prohibit the first wireless base station device from using the first beam or prohibit the second wireless base station device from using the second beam in a case where the estimation unit estimates that the range of the first beam is correlated with the range of the second beam.
1 . A wireless communication system comprising a communication control device and a plurality of wireless base station devices capable of forming a plurality of beams and transmitting signals,
wherein the communication control device comprises:
an estimation circuitry configured to estimate whether or not a range of a first beam emitted by a first wireless base station device among the plurality of wireless base station devices is correlated with a range of a second beam emitted by a second wireless base station device different from the first wireless base station device; and
a use prohibition circuitry configured to prohibit in performing a beam search, the first wireless base station device from transmitting the first beam of the plurality of beams of the first wireless base station device, or prohibit the second wireless base station device from transmitting the second beam of the plurality of beams of the second wireless base station device, in a case where the estimation circuitry estimates that the range of the first beam is correlated with the range of the second beam.
2 . The wireless communication system according to claim 1 , wherein the estimation circuitry
derives a correlation coefficient using reception power when a wireless terminal station receives the first beam and the reception power when the wireless terminal station receives the second beam, the reception power being obtained for a certain period dating back from a current time point, or being a latest N pieces of reception power, and
estimates that the range of the first beam is correlated with the range of the second beam in a case where the derived correlation coefficient is equal to or greater than a predetermined value.
3 . The wireless communication system according to claim 1 , wherein the estimation circuitry
derives a forgetting coefficient type correlation coefficient using reception power when a wireless terminal station receives the first beam and the reception power when the wireless terminal station receives the second beam, the reception power being obtained for a certain period dating back from a current time point, or being a latest N pieces of reception power, and
estimates that the range of the first beam is correlated with the range of the second beam in a case where the derived correlation coefficient is equal to or greater than a predetermined value.
4 . The wireless communication system according to claim 1 , wherein the use prohibition circuitry randomly determines a beam for which use is to be prohibited between the first beam and the second beam or determines the beam by a round robin method.
5 . The wireless communication system according to claim 1 , wherein the use prohibition circuitry prohibits use-transmission of a beam emitted by a wireless base station having a larger number of accommodated wireless terminal stations, among the first beam emitted by the first wireless base station device and the second beam emitted by the second wireless base station device.
6 . The wireless communication system according to claim 1 , wherein
each of the plurality of wireless base station devices comprises:
a wireless circuitry configured to transmit the plurality of beams and receive, from a wireless terminal station, feedback information which includes an identifier of a beam whose reception power is a maximum and the reception power of the beam; and
a communication control circuitry configured to transmit the received feedback information to the communication control device,
wherein the estimation circuitry of the communication control device estimates whether or not the range of the first beam is correlated with the range of the second beam, based on the reception power of the beam whose reception power is the maximum included in each of the feedback information received from the plurality of wireless base station devices.
7 . A method for controlling a communication control device in a wireless communication system comprising the communication control device and a plurality of wireless base station devices capable of forming a plurality of beams and transmitting signals, the method comprising:
estimating whether or not a range of a first beam emitted by a first wireless base station device among the plurality of wireless base station devices is correlated with a range of a second beam emitted by a second wireless base station device different from the first wireless base station device; and
prohibiting in performing a beam search, the first wireless base station device from transmitting the first beam of the plurality of beams of the first wireless base station device, or prohibiting the second wireless base station device from transmitting the second beam of the plurality of beams of the second wireless base station device, in a case where it is estimated in the estimating that the range of the first beam is correlated with the range of the second beam.
8 . A communication control device in a wireless communication system comprising the communication control device and a plurality of wireless base station devices capable of forming a plurality of beams and transmitting signals, the communication control device comprising:
an estimation circuitry configured to estimate whether or not a range of a first beam emitted by a first wireless base station device among the plurality of wireless base station devices is correlated with a range of a second beam emitted by a second wireless base station device different from the first wireless base station device; and
a use prohibition circuitry configured to prohibit in performing a beam search, the first wireless base station device from transmitting the first beam of the plurality of beams of the first wireless base station device, or prohibit the second wireless base station device from transmitting the second beam of the plurality of beams of the second wireless base station device, in a case where the estimation circuitry estimates that the range of the first beam is correlated with the range of the second beam.
9 . The communication control device according to claim 8 , wherein the estimation circuitry
derives a correlation coefficient using reception power when a wireless terminal station receives the first beam and the reception power when the wireless terminal station receives the second beam, the reception power being obtained for a certain period dating back from a current time point, or being a latest N pieces of reception power, and
estimates that the range of the first beam is correlated with the range of the second beam in a case where the derived correlation coefficient is equal to or greater than a predetermined value.