Base station, terminal apparatus, communication method and recording medium
A method and device for selecting a beam used in communication in an environment in which massive-MIMO beamforming is performed, to include a base station including: a communication unit configured to form multiple beams and perform communication with a terminal apparatus; and a control unit configured to transmit, to the terminal apparatus, first identification information of a group that is used in communication with the terminal apparatus among the first identification information allocated to groups each of which includes multiple beams to be formed.
1. A base station comprising:
circuitry comprising a transceiver and a processor, the circuitry being configured to:
transmit a plurality of beams included in a beam group, each beam comprising a synchronization signal for a terminal device to perform a time synchronization with the base station, wherein the one or more beams are included in a beam group and wherein the synchronization signal comprises a time synchronization signal for the time synchronization and a broadcast signal for an initial access procedure,
wherein the plurality of beams are orthogonal to each other,
send, to the terminal device, synchronization information, the synchronization information being for a synchronization in a time domain between the terminal device and the base station and comprising:
timing information regarding the synchronization in the time domain between the terminal device and the base station, and
information regarding the beam group; and
receive, from the terminal device, information indicating a beam identifier of a beam from among the transmitted plural beams in the beam group,
wherein the beam is determined by the terminal device based on a reception quality of the transmitted plural beams included in the beam group.
2. The base station according to the claim 1 , wherein the processor is further configured to periodically transmit the plural beams.
3. The base station according to the claim 2 , wherein the beam-group specific synchronization signal is used by the terminal device to perform a cell search.
4. The base station according to the claim 2 , wherein the processor is further configured to perform cell search by using the beam-group specific synchronization signal.
5. A terminal device comprising:
circuitry comprising a transceiver and a processor, the circuitry being configured to:
receive from a base station, a plurality of beams included in a beam group, plural beams comprising a beam-group specific synchronization signal, each beam comprising a synchronization signal for a terminal device to perform a time synchronization with the base station, wherein the one or more beams are included in a beam group and wherein the synchronization signal comprises a time synchronization signal for the time synchronization and a broadcast signal for an initial access procedure,
wherein the plurality of beams are orthogonal to each other,
receive synchronization information, the synchronization information being for a synchronization in a time domain between the terminal device and the base station and comprising:
timing information regarding the synchronization in the time domain between the terminal device and the base station, and
information regarding the beam group; and
transmit, to the base station, information indicating a beam identifier of a beam from among the transmitted plural beams in the beam group,
wherein the beam is determined by the terminal device based on a reception quality of the transmitted plural beams included in the beam group.
6. The terminal device according to the claim 5 , wherein the plural beams are periodically transmitted from the base station.
7. A method for a base station, the method comprising:
transmitting a plurality of beams included in a beam group, each beam comprising a synchronization signal for a terminal device to perform a time synchronization with the base station, wherein the one or more beams are included in a beam group and wherein the synchronization signal comprises a time synchronization signal for the time synchronization and a broadcast signal for an initial access procedure,
wherein the plurality of beams are orthogonal to each other,
sending, to the terminal device, synchronization information, the synchronization information being for a synchronization in a time domain between the terminal device and the base station and comprising:
timing information regarding the synchronization in the time domain between the terminal device and the base station, and
information regarding the beam group; and
receiving, from the terminal device, information indicating a beam identifier of a beam from among the transmitted plural beams in the beam group,
wherein the beam is determined by the terminal device based on a reception quality of the transmitted plural beams included in the beam group.
8. A method for a terminal device, the method comprising:
receiving from a base station, a plurality of beams included in a beam group, plural beams comprising a beam-group specific synchronization signal, each beam comprising a synchronization signal for a terminal device to perform a time synchronization with the base station, wherein the one or more beams are included in a beam group and wherein the synchronization signal comprises a time synchronization signal for the time synchronization and a broadcast signal for an initial access procedure,
wherein the plurality of beams are orthogonal to each other,
receiving synchronization information, the synchronization information being for a synchronization in a time domain between the terminal device and the base station and comprising:
timing information regarding the synchronization in the time domain between the terminal device and the base station, and
information regarding the beam group; and
transmitting, to the base station, information indicating a beam identifier of a beam from among the transmitted plural beams in the beam group,
wherein the beam is determined by the terminal device based on a reception quality of the transmitted plural beams included in the beam group.