Patent ID: 8301084
Filing Date: 2012-10-30
Classification: H03H,H04B

Abstract:
1. A radio frequency (RF) transceiver front end circuit with a predefined operating frequency for connecting a transceiver to an antenna, the front end circuit comprising: an antenna port connectible to the antenna; a transmit port; a receive port; a power amplifier including a first power amplifier transistor having a base coupled to the transmit port, a collector, and an emitter; a power amplifier input matching network coupling the transmit port and the base of the first power amplifier transistor; a power amplifier control circuit with a first adjustable voltage source coupled to the base of the first power amplifier transistor, the power amplifier control circuit activating and setting a bias point of the first power amplifier transistor; a low noise amplifier including a first low noise amplifier transistor having a base, a collector coupled to the receive port, and an emitter; a low noise amplifier output matching network coupling the receive port and the collector of the first low noise amplifier transistor; a low noise amplifier control circuit with a second adjustable voltage source coupled to the base of the first low noise amplifier transistor, the low noise amplifier control circuit activating and setting a bias point of the first low noise amplifier transistor; a direct current bias switch coupled to the low noise amplifier and activated by the low noise amplifier control circuit; and a matching circuit including a power amplifier output matching segment coupled to the collector of the first power amplifier transistor and the antenna port, and a low noise amplifier input matching segment coupled to the base of the first low noise amplifier transistor and the antenna port, the power amplifier matching segment having shared components with the low noise amplifier segment.