公开(公告)号：US09991938B2

公开(公告)日：2018-06-05

申请号：US15674263

申请日：2017-08-10

Applicant: National Instruments Corporation

Inventor： Nikhil U. Kundargi ,  Karl F. Nieman ,  Junmo Sung

IPC: H04B7/04 ,  H04B7/0413 ,  H04L5/00 ,  H04B17/11 ,  H04W88/08 ,  H04B7/06

CPC classification number: H04B7/0413 ,  H04B7/0617 ,  H04B17/11 ,  H04B17/14 ,  H04L5/001 ,  H04L5/0023 ,  H04L5/0048 ,  H04L5/0051 ,  H04L25/0202 ,  H04L27/2613 ,  H04W72/0453 ,  H04W72/085 ,  H04W88/02 ,  H04W88/08

Abstract: A wireless cellular base station includes M antennas and one or more processing devices. For each antenna, the antenna transmits a calibration pilot symbol over the air and the other M−1 antennas receive the calibration pilot symbol over the air. The processing devices select one of the M antennas as a reference antenna and for each antenna of the M antennas, the processing devices calculate channel reciprocity calibration coefficients of the antenna with respect to the reference antenna based on the received calibration pilot symbols.

公开(公告)号：US20180048361A1

公开(公告)日：2018-02-15

申请号：US15674263

申请日：2017-08-10

Applicant: National Instruments Corporation

Inventor： Nikhil U. Kundargi ,  Karl F. Nieman ,  Junmo Sung

IPC: H04B7/0413 ,  H04B17/11 ,  H04L5/00

CPC classification number: H04B7/0413 ,  H04B7/0617 ,  H04B17/11 ,  H04B17/14 ,  H04L5/001 ,  H04L5/0023 ,  H04L5/0048 ,  H04L5/0051 ,  H04L25/0202 ,  H04L27/2613 ,  H04W72/0453 ,  H04W72/085 ,  H04W88/02 ,  H04W88/08

Abstract: A wireless cellular base station includes M antennas and one or more processing devices. For each antenna, the antenna transmits a calibration pilot symbol over the air and the other M−1 antennas receive the calibration pilot symbol over the air. The processing devices select one of the M antennas as a reference antenna and for each antenna of the M antennas, the processing devices calculate channel reciprocity calibration coefficients of the antenna with respect to the reference antenna based on the received calibration pilot symbols.

公开(公告)号：US20190280741A1

公开(公告)日：2019-09-12

申请号：US16392039

申请日：2019-04-23

Applicant: National Instruments Corporation

Inventor： Nikhil U. Kundargi ,  Karl F. Nieman ,  Junmo Sung

IPC: H04B7/0413 ,  H04L5/00 ,  H04W72/04 ,  H04W72/08 ,  H04L25/02 ,  H04B17/11 ,  H04B17/14 ,  H04L27/26

Abstract: A wireless cellular base station (BS) transmitter transmits a downlink calibration pilot symbol. A receiver receives from a user equipment (UE) an uplink calibration pilot symbol and an effective downlink channel estimate transmitted by the UE. The effective downlink channel estimate is computed by the UE using the downlink calibration pilot symbol received from the BS. Processing devices compute an effective uplink channel estimate using the uplink calibration pilot symbol received from the UE and compute channel reciprocity calibration coefficients using the effective downlink channel estimate received from the UE and the effective uplink channel estimate computed by the BS. The BS includes multiple antennas, and the BS computes the channel reciprocity calibration coefficients for each antenna. Alternatively, the uplink channel estimate received by the BS is an inverted version of the effective downlink channel estimate, which the processing devices use for channel reciprocity compensation.

公开(公告)号：US10958314B2

公开(公告)日：2021-03-23

申请号：US16392039

申请日：2019-04-23

Applicant: National Instruments Corporation

Inventor： Nikhil U. Kundargi ,  Karl F. Nieman ,  Junmo Sung

IPC: H04B7/0413 ,  H04B17/11 ,  H04L5/00 ,  H04B17/14 ,  H04L27/26 ,  H04L25/02 ,  H04L25/03 ,  H04W72/04 ,  H04W72/08 ,  H04W88/08 ,  H04B7/06 ,  H04W88/02

Abstract: A wireless cellular base station (BS) transmitter transmits a downlink calibration pilot symbol. A receiver receives from a user equipment (UE) an uplink calibration pilot symbol and an effective downlink channel estimate transmitted by the UE. The effective downlink channel estimate is computed by the UE using the downlink calibration pilot symbol received from the BS. Processing devices compute an effective uplink channel estimate using the uplink calibration pilot symbol received from the UE and compute channel reciprocity calibration coefficients using the effective downlink channel estimate received from the UE and the effective uplink channel estimate computed by the BS. The BS includes multiple antennas, and the BS computes the channel reciprocity calibration coefficients for each antenna. Alternatively, the uplink channel estimate received by the BS is an inverted version of the effective downlink channel estimate, which the processing devices use for channel reciprocity compensation.

公开(公告)号：US10447352B2

公开(公告)日：2019-10-15

申请号：US15674282

申请日：2017-08-10

Applicant: National Instruments Corporation

Inventor： Nikhil U. Kundargi ,  Karl F. Nieman ,  Junmo Sung

IPC: H04B7/0413 ,  H04B17/11 ,  H04L5/00 ,  H04L25/02 ,  H04W72/04 ,  H04W72/08 ,  H04L27/26 ,  H04B17/14 ,  H04W88/08 ,  H04B7/06 ,  H04W88/02

Abstract: A wireless cellular base station (BS) transmitter transmits a downlink calibration pilot symbol. A receiver receives from a user equipment (UE) an uplink calibration pilot symbol and an effective downlink channel estimate transmitted by the UE. The effective downlink channel estimate is computed by the UE using the downlink calibration pilot symbol received from the BS. Processing devices compute an effective uplink channel estimate using the uplink calibration pilot symbol received from the UE and compute channel reciprocity calibration coefficients using the effective downlink channel estimate received from the UE and the effective uplink channel estimate computed by the BS. The BS includes multiple antennas, and the BS computes the channel reciprocity calibration coefficients for each antenna. Alternatively, the uplink channel estimate received by the BS is an inverted version of the effective downlink channel estimate, which the processing devices use for channel reciprocity compensation.

公开(公告)号：US20180048492A1

公开(公告)日：2018-02-15

申请号：US15674282

申请日：2017-08-10

Applicant: National Instruments Corporation

Inventor： Nikhil U. Kundargi ,  Karl F. Nieman ,  Junmo Sung

IPC: H04L25/02 ,  H04L5/00 ,  H04W72/04 ,  H04B7/0413 ,  H04W72/08

CPC classification number: H04B7/0413 ,  H04B7/0617 ,  H04B17/11 ,  H04B17/14 ,  H04L5/001 ,  H04L5/0023 ,  H04L5/0048 ,  H04L5/0051 ,  H04L25/0202 ,  H04L25/0204 ,  H04L25/0224 ,  H04L25/0398 ,  H04L27/2613 ,  H04W72/0453 ,  H04W72/085 ,  H04W88/02 ,  H04W88/08

Abstract: A wireless cellular base station (BS) transmitter transmits a downlink calibration pilot symbol. A receiver receives from a user equipment (UE) an uplink calibration pilot symbol and an effective downlink channel estimate transmitted by the UE. The effective downlink channel estimate is computed by the UE using the downlink calibration pilot symbol received from the BS. Processing devices compute an effective uplink channel estimate using the uplink calibration pilot symbol received from the UE and compute channel reciprocity calibration coefficients using the effective downlink channel estimate received from the UE and the effective uplink channel estimate computed by the BS. The BS includes multiple antennas, and the BS computes the channel reciprocity calibration coefficients for each antenna. Alternatively, the uplink channel estimate received by the BS is an inverted version of the effective downlink channel estimate, which the processing devices use for channel reciprocity compensation.