Terminal apparatus, base station, and program

1. A terminal apparatus comprising:

a wireless communication transceiver configured to perform wireless communication with a base station; and

controller circuitry configured to receive a transmitted reference signal from the base station and perform measurement of the transmitted reference signal, a plurality of transmission weights being applied by the base station to the transmitted reference signal for beamforming, the plurality of transmission weights stored at the base station, wherein the base station applies the plurality of transmission weights to the transmitted reference signal by multiplying the transmitted reference signal with the plurality of transmission weights,

wherein the controller circuitry performs the measurement by calculating the sum of the plurality of transmission weights for beamforming, and multiplying a channel for the reference signal before application by the sum of the plurality of transmission weights for beamforming, and thereby calculating received power which occurs when the reference signal after application of the plurality of transmission weights for beamforming is received by the wireless communication transceiver,

wherein the terminal apparatus communicates with a base station which has been selected based on the measurement of the transmitted reference signal.

2. The terminal apparatus according to claim 1 , wherein

the plurality of transmission weights for beamforming are beamforming transmission weights which are particularly used by the base station, among a universal set of beamforming transmission weights.

3. The terminal apparatus according to claim 2 ,

wherein the wireless communication transceiver receives the reference signal before application of the plurality of transmission weights for beamforming, the reference signal having been transmitted from the base station, and

the controller circuitry applies the plurality of transmission weights for beamforming to the reference signal before application.

4. The terminal apparatus according to claim 3 ,

wherein the wireless communication transceiver receives system information containing information indicating the plurality of transmission weights for beamforming.

5. The terminal apparatus according to claim 3 ,

wherein the wireless communication transceiver receives system information containing information indicating a sum of the plurality of transmission weights for beamforming.

6. The terminal apparatus according to claim 1 ,

wherein the controller circuitry performs the measurement by calculating reception quality which occurs when the reference signal after the application is received by the wireless communication transceiver, on the basis of the calculated received power.

7. The terminal apparatus according to claim 2 ,

wherein the wireless communication transceiver receives the reference signal after application of the plurality of transmission weights for beamforming.

8. The terminal apparatus according to claim 7 ,

wherein the controller circuitry performs the measurement by acquiring a channel for the reference signal after the application, and calculating received power of the reference signal after the application.

9. The terminal apparatus according to claim 8 ,

wherein the controller circuitry performs the measurement by calculating received power of the reference signal after the application, on the basis of the calculated received power.

10. The terminal apparatus according to claim 7 ,

wherein the wireless communication transceiver receives the reference signal before application of the plurality of transmission weights for beamforming, and

the controller circuitry determines a precoding matrix indicator (PMI) using the reference signal before the application, and feeds the PMI back to the base station.

11. The terminal apparatus according to claim 1 ,

wherein the measurement includes measurement of reference signal received power (RSRP) or reference signal received quality (RSRQ).

12. A base station comprising:

a wireless communication transceiver configured to perform wireless communication with a terminal apparatus; and

controller circuitry configured to control the wireless communication transceiver in a manner that the wireless communication transceiver transmits information indicating a plurality of transmission weights stored at the base station for beamforming and a measurement reference signal to the terminal apparatus, before application of the plurality of transmission weights by the terminal apparatus, the application of the plurality of transmission weights comprising multiplication of the plurality of transmission weights with the measurement reference signal by the terminal apparatus,

wherein the terminal apparatus performs a measurement of signal strength which has been received by calculating the sum of the plurality of transmission weights for beamforming, and multiplying a channel for the reference signal before application by the sum of the plurality of transmission weights for beamforming, and thereby calculating received power which occurs when the reference signal after application of the plurality of transmission weights for beamforming is received by the terminal apparatus,

wherein the terminal apparatus communicates with a base station which has been selected based on the measurement of the transmitted reference signal.

13. The base station according to claim 12 ,

wherein the controller circuitry maps the reference signal before the application to a resource element for transmission of a cell-specific reference signal (CRS).

14. A base station comprising:

a wireless communication transceiver configured to perform wireless communication with a terminal apparatus; and

controller circuitry configured to control the wireless communication transceiver in a manner that the wireless communication transceiver transmits a measurement reference signal after application of a plurality of transmission weights stored at the base station, for beamforming, the application of the plurality of transmission weights comprising multiplication of the measurement reference signal with the plurality of transmission weights,

wherein the terminal apparatus performs a measurement of signal strength which has been received by calculating the sum of the plurality of transmission weights for beamforming, and multiplying a channel for the reference signal before application by the sum of the plurality of transmission weights for beamforming, and thereby calculating received power which occurs when the reference signal after application of the plurality of transmission weights for beamforming is received by the terminal apparatus,

wherein the terminal apparatus communicates with a base station which has been selected based on the measurement of the transmitted reference signal.

15. The base station according to claim 14 ,

wherein the controller circuitry maps the reference signal after the application to a CRS transmission resource element.

16. The base station according to claim 14 ,

wherein the controller circuitry’ controls the wireless communication transceiver in a manner that the wireless communication transceiver transmits the reference signal before application of the plurality of transmission weights for beamforming.

17. The base station according to claim 14 ,

wherein the controller circuitry limits operation of the terminal apparatus in an operation mode involving PMI feedback.

18. A non-transitory computer-readable storage medium including computer executable instructions, wherein the instructions, when executed, cause a computer at a base station to perform:

wireless communication with a terminal apparatus; and

controlling the wireless communication to transmit information indicating a plurality of transmission weights stored at the base station for beamforming and a measurement reference signal to the terminal apparatus, before application of the plurality of transmission weights by the terminal apparatus, the application of the plurality of transmission weights comprising multiplication of the plurality of transmission weights with the measurement reference signal by the terminal apparatus,

wherein the terminal apparatus performs a measurement of signal strength which has been received by calculating the sum of the plurality of transmission weights for beamforming, and multiplying a channel for the reference signal before application by the sum of the plurality of transmission weights for beamforming, and thereby calculating received power which occurs when the reference signal after application of the plurality of transmission weights for beamforming is received by the terminal apparatus,

wherein the terminal apparatus communicates with a base station which has been selected based on the measurement of the transmitted reference signal.

19. A non-transitory computer-readable storage medium including computer executable instructions, wherein the instructions, when executed, cause a computer at a base station to perform:

wireless communication with a terminal apparatus; and

controlling of the wireless communication to transmit a measurement reference signal after application of a plurality of transmission weights stored at the base station, for beamforming, the application of the plurality of transmission weights comprising multiplication of the measurement reference signal with the plurality of transmission weights,

wherein the terminal apparatus performs a measurement of signal strength which has been received by calculating the sum of the plurality of transmission weights for beamforming, and multiplying a channel for the reference signal before application by the sum of the plurality of transmission weights for beamforming, and thereby calculating received power which occurs when the reference signal after application of the plurality of transmission weights for beamforming is received by the terminal apparatus,

wherein the terminal apparatus communicates with a base station which has been selected based on the measurement of the transmitted reference signal.