Apparatus, method, system, program and recording medium related to beamforming

Abstract

[Object] To make it possible to further increase a possibility of a success in a handover.[Solution] A first apparatus of the present invention includes: a first communication processing unit configured to transmit reference signals using beamforming; and a second communication processing unit configured to receive a handover message from a source base station of a handover of a terminal apparatus. The handover message includes beam related information related to a beam. The first communication processing unit is configured to receive an access signal of the terminal apparatus based on the beam related information.

What is claimed is: 
     
         1 . A method of a terminal apparatus configured to communicate with a first base station, the method comprising:
 performing measurements of signals transmitted by a second base station using at least one beam;   transmitting, to the first base station, first information indicating results of the measurements;   receiving an RRC message from the first base station, the RRC message including second information related to a beam;   wherein the RRC message included in a acknowledge message is transmitted from the second base station to the first base station in response to a request message, and   wherein the request message including the first information is transmitted from the first base station to the second base station; and   transmitting, to the second base station, a random access preamble signal based on the second information.   
     
     
         2 . The method according to  claim 1 ,
 wherein the acknowledge message includes a container to be sent to the terminal apparatus to perform the handover from the first base station to the second base station.   
     
     
         3 . The method according to  claim 1 ,
 wherein the request message is a HANDOVER REQUEST message, and   wherein the acknowledge message is a HANDOVER REQUEST ACKNOWLEDGE message.   
     
     
         4 . The method according to  claim 1 ,
 wherein the results of measurements include preferred beamforming weights that correspond to the beam.   
     
     
         5 . The method according to  claim 1 ,
 wherein the second information includes information regarding a resource for the beam.   
     
     
         6 . The method according to  claim 1 ,
 wherein the second information includes information regarding a retransmission cycle for the beam.   
     
     
         7 . The method according to  claim 5 ,
 wherein the information regarding the resource for the beam is Dedicated Random Access Channel (RACH) Resource Information.   
     
     
         8 . The method according to  claim 6 ,
 wherein the information regarding the retransmission cycle for the beam is Dedicated RACH Retransmission cycle Information.   
     
     
         9 . A terminal apparatus configured to communicate with a first base station, the terminal apparatus comprising:
 a processor performing measurements of signals transmitted by a second base station using at least one beam;   a transmitter transmitting, to the first base station, first information indicating results of the measurements and;   a receiver receiving an RRC message from the first base station, the RRC message including second information related to a beam;   wherein the RRC message included in a acknowledge message is transmitted from the second base station to the first base station in response to a request message, and   wherein the request message including the first information is transmitted from the first base station to the second base station; and   wherein the transmitter transmits a random access preamble signal based on the second information to the second base station.   
     
     
         10 . A method of a second base station configured to communicate with a first base station and a terminal apparatus, the method comprising:
 transmitting a acknowledge message including an RRC message including second information related to a beam to the first base station in response to a request message and;   receiving the request message including first information indicating results of the measurements from the first base station and a random access preamble signal from the terminal apparatus based on the second information.