US 12,149,382 B2
Wireless circuitry with narrowband error vector magnitude (EVM) estimator
Andrea Camuffo, Munich (DE)
Assigned to Apple Inc., Cupertino, CA (US)
Filed by Apple Inc., Cupertino, CA (US)
Filed on Jul. 29, 2022, as Appl. No. 17/876,916.
Prior Publication US 2024/0039764 A1, Feb. 1, 2024
Int. Cl. H04L 25/02 (2006.01); H03F 1/32 (2006.01)
CPC H04L 25/0204 (2013.01) [H03F 1/32 (2013.01); H04L 25/0224 (2013.01)] 19 Claims
OG exemplary drawing
 
1. Circuitry comprising:
a first filter configured to receive a reference signal;
a second filter configured to receive a demodulated signal from an output of a radio-frequency amplifier;
a first signal extraction circuit coupled to an output of the first filter;
a second signal extraction circuit coupled to an output of the second filter;
a comparison circuit having a first input coupled to an output of the first signal extraction circuit, a second input coupled to an output of the second signal extraction circuit, and an output on which an estimated value is computed, the estimated value being used to adjust the radio-frequency amplifier;
a multiplexer having an output coupled to the radio-frequency amplifier;
a control circuit coupled to a first input of the multiplexer and configured to receive the estimated value; and
envelope tracking circuitry coupled to a second input of the multiplexer and configured to receive the reference signal.