Patent ID: 8436694
Filing Date: 2013-05-07
Classification: H03F,H03H,H04B

Abstract:
1. A circuit for adaptive matching of a load impedance to a predetermined load-line impedance of a load-line connected to a power amplifier output, the circuit comprising: a variable impedance matching network coupled to the load impedance for transformation of the load impedance to a matched impedance, wherein the variable impedance matching network comprises at least one variable circuit element having an impedance that is controllable by a control setting input such that matching by the variable impedance matching network is controllable by a control setting applied to the control setting input; and a fixed impedance inverting network coupled to the variable impedance matching network for transformation of the matched impedance to the predetermined load-line impedance; wherein the variable impedance matching network is feed forward controlled by a control circuit, the control circuit comprising a look-up table with stored calibration data of the variable impedance matching network, wherein the calibration data is mapped to several different output power levels of the power amplifier.