US 12,425,067 B2
Radio transmitter as well as method and controller therefor
Ling Qin, Chengdu (CN); and Rui Hou, Täby (SE)
Assigned to TELEFONAKTIEBOLAGET LM ERICSSON (PUBL), Stockholm (SE)
Appl. No. 18/029,795
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed Oct. 2, 2020, PCT No. PCT/CN2020/119789
§ 371(c)(1), (2) Date Mar. 31, 2023,
PCT Pub. No. WO2022/067855, PCT Pub. Date Apr. 7, 2022.
Prior Publication US 2023/0370110 A1, Nov. 16, 2023
Int. Cl. H04B 1/525 (2015.01); H04B 1/04 (2006.01)
CPC H04B 1/525 (2013.01) [H04B 2001/0408 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A radio transmitter comprising:
a power amplifier;
a filter unit capable of filtering an output from the power amplifier during a downlink time division duplex (TDD) slot and filtering an uplink signal during an uplink TDD slot;
a circulator having a first port coupled to the power amplifier, a second port coupled to the filter unit, and a third port coupled to a switch;
the switch capable of coupling the third port of the circulator to a termination load during the downlink TDD slot and coupling the third port of the circulator to an uplink reception path during the uplink TDD slot; and
a reflection cancellation unit which is coupled between the switch and the termination load and is capable of generating a first reflection signal that propagates to the first port of the circulator via the switch and the third port of the circulator during the downlink TDD slot.