The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 28, 2021
Filed:
Oct. 20, 2017
Telefonaktiebolaget Lm Ericsson (Publ), Stockholm, SE;
Zhanxian Wang, Täby, SE;
Christian Braun, Vallentuna, SE;
Telefonaktiebolaget LM Ericsson (Publ), Stockholm, SE;
Abstract
The present disclosure relates to over-the-air, OTA, reciprocity calibration for a distributed multiple input-multiple output, D-MIMO, system. By having antennas of the system divided in two separate groups, based on pairwise path loss, and by performing two measurements only, one of which is transmitting by the first group and simultaneously receiving by the second group, and the second by transmitting by the second group and simultaneously receiving by the first group, relations between receiver and transmitter impairments used in the measurements are determined, assuming reciprocity. By relating receive to transmitter impairments for each antenna relative to one or more anchor antennas, calibration values are calculated. By adjusting a quota of the receiver to the transmitter impairment for each antenna such that the relations are fulfilled, reciprocity calibration is achieved, based on two measurements only.