US 12,191,939 B2
Multiple-input multiple-output transmission and reception
Linglong Dai, London (GB); Talha Mir, London (GB); Muhammad Siddiqi, London (GB); Mo Hao, London (GB); and Richard Mackenzie, London (GB)
Assigned to British Telecommunications Public Limited Company, (GB)
Appl. No. 17/594,354
Filed by British Telecommunications public limited company, London (GB)
PCT Filed Apr. 6, 2020, PCT No. PCT/EP2020/059764
§ 371(c)(1), (2) Date Oct. 12, 2021,
PCT Pub. No. WO2020/207973, PCT Pub. Date Oct. 15, 2020.
Claims priority of application No. 201910283582.1 (CN), filed on Apr. 10, 2019.
Prior Publication US 2022/0190888 A1, Jun. 16, 2022
Int. Cl. H04B 7/0426 (2017.01); H04B 7/0456 (2017.01); H04B 7/06 (2006.01); H04B 7/08 (2006.01); H04B 7/185 (2006.01); H04W 52/02 (2009.01)
CPC H04B 7/0426 (2013.01) [H04B 7/0456 (2013.01); H04B 7/0693 (2013.01); H04B 7/0877 (2013.01); H04B 7/18502 (2013.01); H04W 52/0251 (2013.01); H04W 52/028 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A Multiple-Input Multiple-Output (MIMO) transmitter comprising:
a digital signal processor configured to perform pre-coding on a plurality of data streams;
a plurality of radio-frequency (RF) chains each configured to pass a pre-coded data stream from the digital signal processor to generate a signal representing that pre-coded data stream;
an antenna array comprising a plurality of antenna elements;
a switching unit configured to connect the plurality of RF chains to the plurality of antenna elements in one of a first state or a second state in which:
in the first state, at least one RF chain of the plurality of RF chains is connected to a first subset of the plurality of the antenna elements, and
in the second state, the at least one RF chain of the plurality of RF chains is connected to a second subset of the plurality of antenna elements, wherein the first subset and the second subset in respect of the at least one RF chain have a different number of antenna elements; and
a power control unit configured to determine an energy availability measure based on at least one of a present measurement or a past measurement of a state of a power source from which the MIMO transmitter obtains power and, in response, cause the switching unit to connect the plurality of RF chains to the plurality of antenna elements in either the first state or the second state.