US 12,392,865 B2
Transmit power reduction for radio frequency transmitters
Herbert Knapp, Munich (DE); and Hao Li, Poing (DE)
Assigned to Infineon Technologies AG, Neubiberg (DE)
Filed by Infineon Technologies AG, Neubiberg (DE)
Filed on Dec. 10, 2021, as Appl. No. 17/547,907.
Prior Publication US 2023/0184885 A1, Jun. 15, 2023
Int. Cl. G01S 7/35 (2006.01); G01S 13/32 (2006.01); H03F 3/24 (2006.01)
CPC G01S 7/35 (2013.01) [G01S 7/358 (2021.05); H03F 3/245 (2013.01); G01S 13/325 (2013.01); H03F 2200/451 (2013.01)] 22 Claims
OG exemplary drawing
 
1. A method of operating a radar transmitter, the method comprising:
supplying a first radio frequency (RF) signal to a phase shifter, wherein the phase shifter comprises an in-phase (I) component RF path and a quadrature (Q) component RF path, wherein the I-component RF path and the Q-component RF path are configured to generate a phase shift to the first RF signal according to a first scale factor of the I-component RF path and a second scale factor of the Q-component RF path, wherein the phase shifter is configured to generate a second RF signal at an output terminal of the phase shifter, wherein the output terminal of the phase shifter is coupled to an input terminal of a power amplifier of the radar transmitter;
generating an enable signal for the power amplifier, wherein the enable signal is a binary digital control signal that alternates between a first value and a second value during operation of the radar transmitter;
passing the second RF signal from the phase shifter through the power amplifier by setting the enable signal for the power amplifier to the first value;
after passing the second RF signal, setting the enable signal for the power amplifier to the second value to reduce a gain of the power amplifier; and
based on setting the enable signal to the second value, reducing a power of the second RF signal by setting the first scale factor of the I-component RF path and the second scale factor of the Q-component RF path.