公开(公告)号：US20240323726A1

公开(公告)日：2024-09-26

申请号：US18124801

申请日：2023-03-22

申请人： KDDI Research, Inc. ,  University of Southern California

发明人： Masaaki ITO ,  Issei KANNO ,  Kosuke YAMAZAKI ,  Andreas F. MOLISCH

IPC分类号： H04W24/10

CPC分类号： H04W24/10

摘要： A method performed by a processing apparatus of a cell-free communication system that includes a plurality of access points (APs) is provided. The method includes: transmitting, to a wireless device via a master AP among one or more APs included in a cluster associated with the wireless device, measurement information for the wireless device to determine a measurement target AP for which the wireless device measures a channel state; and receiving, as a response to the measurement information, channel state information indicating the channel state to the measurement target AP, via the master AP.

公开(公告)号：US20240323762A1

公开(公告)日：2024-09-26

申请号：US18124808

申请日：2023-03-22

申请人： KDDI Research, Inc. ,  University of Southern California

发明人： Masaaki ITO ,  Issei KANNO ,  Yoshiaki AMANO ,  Andreas F. MOLISCH

IPC分类号： H04W28/086 ,  H04W72/121

CPC分类号： H04W28/086 ,  H04W72/121

摘要： The method includes: executing, when first APs that are changed from a cluster AP to a non-cluster AP due to a change of a cluster occurs, first processing on processing target APs including the first APs and a second AP that is the non-cluster AP satisfying a predetermined condition in relation to the first APs, and thereby determining, as an operation mode of the processing target APs. The first processing includes: selecting one first processing target AP from the processing target APs, and determining a downstream-only mode as the operation mode of the one first processing target AP, and determining a upstream-only mode or a sleep mode as the operation mode of a second processing target AP that is different from the one first processing target AP and is among the processing target APs.

公开(公告)号：US20210167996A1

公开(公告)日：2021-06-03

申请号：US17045214

申请日：2019-04-03

申请人： UNIVERSITY OF SOUTHERN CALIFORNIA

发明人： Vishnu Vardhan RATNAM ,  Andreas F. MOLISCH

IPC分类号： H04L25/02 ,  H04B7/0452 ,  H04L27/26

摘要： Novel channel estimation techniques that can be performed solely in the analog domain are provided. The techniques use continuous analog channel estimation (CACE), periodic analog channel estimation (PACE), and multiantenna frequency shift reference (MAFSR). These techniques provide sufficient channel knowledge to enable analog beamforming at the receiver while significantly reducing the estimation overhead. These schemes involve transmission of a reference tone of a known frequency, either continuously along with the data (CACE, MAFSR) or in a separate phase from data (PACE). Analysis of the methods show that sufficient receiver beamforming gain can be achieved in sparse channels by building the beamformer using just the amplitude and phase estimates of the reference tone from each receiver antenna.