Wireless base station and wireless communication method

摘要

A resource determination unit determines at least a part within any downlink subframe as a first resource and determines at least a part of an UpPTS (Uplink Pilot Timeslot) or a part of an uplink subframe as a second resource for transmitting an SRS (Sounding Reference Signal). A transmission path state estimation unit estimates a state of a transmission path to a wireless terminal based on a DRS (Demodulation Reference Signal) included in uplink user data after the first resource is determined and until it receives an SRS, and it estimates a state of the transmission path to the wireless terminal based on an SRS after it received the SRS.

主权项

1. A wireless base station, comprising one or more controllers that:
determine at least a part within any downlink subframe as a first resource for periodically transmitting downlink user data to a wireless terminal, and determine at least a part of an uplink part within a switch subframe or a part of an uplink subframe as a second resource for said wireless terminal to periodically transmit a first sounding reference signal; notify said wireless terminal of determined said second resource; estimate a state of a transmission path to said wireless terminal based on a second sounding reference signal included in uplink user data received from said wireless terminal after determination of said first resource and until reception of said first sounding reference signal from said wireless terminal, and estimate a state of a transmission path to said wireless terminal based on said first sounding reference signal after reception of said first sounding reference signal; and form directivity of a plurality of antennas based on estimated said state of the transmission path, and transmit said downlink user data through said first resource.