US 12,489,490 B2
Distributed antenna system, wireless communication method, and centralized station
Hayato Fukuzono, Musashino (JP); Keita Kuriyama, Musashino (JP); Masafumi Yoshioka, Musashino (JP); and Toshifumi Miyagi, Musashino (JP)
Assigned to NTT, Inc., Tokyo (JP)
Appl. No. 18/260,483
Filed by NTT, Inc., Tokyo (JP)
PCT Filed Jan. 7, 2021, PCT No. PCT/JP2021/000387
§ 371(c)(1), (2) Date Jul. 6, 2023,
PCT Pub. No. WO2022/149245, PCT Pub. Date Jul. 14, 2022.
Prior Publication US 2024/0072847 A1, Feb. 29, 2024
Int. Cl. H04B 7/022 (2017.01); H04B 7/024 (2017.01); H04B 7/0408 (2017.01); H04B 7/0452 (2017.01); H04J 1/00 (2006.01)
CPC H04B 7/022 (2013.01) [H04B 7/0408 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A distributed antenna system comprising:
a plurality of base stations that performs MIMO (multiple input multiple output) transmission to user terminals at an identical frequency; and
an aggregation station that aggregates pieces of information used by the respective base stations, the aggregation station including:
reception circuitry configured to receive, from each of the base stations, communication path information with each of accommodated user terminals, for each user terminal;
determination circuitry configured to determine whether or not two of the base stations and two user terminals are arranged on a straight line on a basis of the communication path information for each user terminal received by the reception circuitry;
NOMA (non-orthogonal multiple access) processing circuitry configured to perform, in a case where the determination circuitry determines that the two of the base stations and the two user terminals are arranged on the straight line, first processing of generating first information for performing setting such that a transmission beam of any one of the base stations arranged on the straight line is stopped and another of the base stations non-orthogonally superimposes and multiplexes pieces of transmission data for the two respective user terminals with a predetermined power difference or power ratio, or second processing of generating second information for performing setting such that each of the two of the base stations arranged on the straight line non-orthogonally superimposes and multiplexes pieces of transmission data for the two respective user terminals with a predetermined power difference or power ratio to increase gains for the respective user terminals by cooperation of transmission beams transmitted by the two of the base stations to the two respective user terminals; and
control circuitry configured to control the transmission beam of each of the two of the base stations arranged on the straight line on a basis of the first information or the second information.