US 11,057,782 B2
Multi-cell coordination system and channel calibration method thereof
Kun-Lin Chiang, Taipei (TW); and Jia-Ming Chen, Taipei (TW)
Assigned to Sercomm Corporation, Taipei (TW)
Filed by Sercomm Corporation, Taipei (TW)
Filed on Dec. 18, 2018, as Appl. No. 16/224,737.
Prior Publication US 2020/0196160 A1, Jun. 18, 2020
Int. Cl. H04W 16/28 (2009.01); H04B 7/0456 (2017.01); H04L 5/00 (2006.01); H04W 72/04 (2009.01); H04B 17/12 (2015.01)
CPC H04W 16/28 (2013.01) [H04B 7/0456 (2013.01); H04B 17/12 (2015.01); H04L 5/0048 (2013.01); H04W 72/046 (2013.01); H04W 72/0453 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A multi-cell coordination system, comprising:
a base station, comprising at least one antenna, wherein the at least one antenna provides a plurality of beams, each of the plurality of beams is configured with a direction, and the base station performs a first precoding on a downlink reference signal to be transmitted via a selected beam of the plurality of beams, wherein the first precoding is based on a beam coding;
a reference apparatus, wherein the reference apparatus receives the downlink reference signal via the selected beam from the base station, and the reference apparatus performs a second precoding on an uplink reference signal to be transmitted via the selected beam, wherein the second precoding is based on the beam coding, and the base station receives the uplink reference signal via the selected beam from the reference apparatus;
a server, used for receiving an uplink channel information from the base station and a downlink channel information from the reference apparatus, wherein the uplink channel information is generated based on the uplink reference signal and the second precoding, and the downlink channel information is generated based on the downlink channel information and the first precoding, and the server obtains a channel calibration coefficient according to the uplink channel information and the downlink channel information, wherein the channel calibration coefficient is used for estimating a downlink channel; and
a second base station, wherein the server obtains a second channel calibration coefficient according to a second uplink channel information and a second downlink channel information between the second base station and the reference apparatus via a second selected beam of the plurality of beams different from the selected beam, the server performs normalization on the channel calibration coefficient according to the second channel calibration coefficient, and the base station estimates the downlink channel via the selected beam according to a normalized channel calibration coefficient.