Patent ID: 8270926
Filing Date: 2012-09-18
Classification: H04B

Abstract:
1. A radio front end comprises: a transformer having a first winding and a second winding, wherein the first winding is operably coupled to an antenna and the second winding is operably coupled to a power amplifier and a low noise amplifier, wherein the power amplifier is enabled when the radio front end is in a transmit mode and the low noise amplifier is enabled when the radio front end is in a receive mode; and an adjustable load operably coupled to the second winding to compensate for differing loads on the second winding in transmit mode when the power amplifier is enabled and receive mode when the low noise amplifier is enabled, wherein the adjustable load is operable to provide a first impedance based on a first impedance selection signal when the radio front end is in a transmit mode and the power amplifier is enabled and provides a second different impedance based on a second impedance selection signal when the radio front end is in a receive mode and the low noise amplifier is enabled such that impedance at the first winding is substantially similar in the transmit mode when the power amplifier is enabled and in the receive mode when the low noise amplifier is enabled.