Base station, terminal apparatus, communication method and recording medium
To appropriately select a beam used in communication in an environment in which massive-MIMO beamforming is performed, there is provided 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 second base station configured to provide Dual Connectivity in cooperation with a first base station, the second base station comprising:
circuitry comprising a transceiver and a processor, the circuitry being configured to:
transmit one or more beams comprising a synchronization signal, for a terminal device to perform a time synchronization with the second 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,
send, to the terminal device via the first base station, synchronization information comprising:
timing information regarding the time synchronization, and
information regarding the beam group; and
receive, from the terminal device, information indicating a beam identifier of a beam determined based on a reception quality from among the transmitted one or more beams.
2. The second base station according to the claim 1 , wherein the processor is further configured to periodically transmit the one or more beams.
3. The second base station according to the claim 2 , wherein the synchronization signal is used by the terminal device to perform a cell search.
4. The second base station according to the claim 3 , wherein the first base station is a Long Term Evolution (LTE) base station and the second base station is a 5G millimeter wave base station.
5. A terminal device configured to perform Dual Connectivity with a first base station and a second base station, the terminal device comprising:
circuitry comprising a transceiver and a processor, the circuitry being configured to:
receive, from the first base station, synchronization information that includes:
timing information regarding a time synchronization, and
information regarding the beam group;
receive, from the second base station, one or more beams comprising a synchronization signal to perform the time synchronization with the second 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; and
transmit, to the second base station, information indicating a beam identifier of a beam determined based on a reception quality from among the transmitted one or more beams.
6. The terminal device according to the claim 5 , wherein the one or more beams are periodically transmitted from the second base station.
7. The terminal device according to the claim 6 , wherein the processor is further configured to perform cell search by using the synchronization signal.
8. The terminal device according to the claim 7 , wherein the first base station is a Long Term Evolution (LTE) base station and the second base station is a 5G millimeter wave base station.
9. A method for a second base station configured to provide Dual Connectivity in cooperation with a first base station, the method comprising:
transmitting, by the first base station, one or more beams comprising a synchronization signal, for a terminal device to perform a time synchronization with the second 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,
sending, to the terminal device via the first base station, synchronization information that includes:
timing information regarding the time synchronization, and
information regarding the beam group; and
receiving, from the terminal device, information indicating a beam identifier of a beam determined based on a reception quality from among the transmitted one or more beams.
10. A method for a terminal device configured to perform Dual Connectivity with a first base station and a second base station, the method comprising:
receiving, from the first base station, synchronization information that includes:
timing information regarding a time synchronization, and
information regarding the beam group;
receiving, from the second base station, one or more beams comprising a synchronization signal to perform the time synchronization with the second 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; and
transmitting, to the second base station, information indicating a beam identifier of a beam determined based on a reception quality from among the transmitted one or more beams.