A compact BiFET front-end module for 802.11a/b/g/n TX/RX and 802.16e RX using a triplexer filter

A compact front-end module (FEM) incorporating WiFi TX/RX paths and WiMAX RX paths is presented. The FEM is dual-band-transmit/tri-band-receive. By integrating InGaP HBT power amplifiers and pHEMT T/R switches on a single die, this functionality is achieved in a 1.4 × 4 × 5.4 mm surface mount module. Assembly involves only one wire-bonded GaAs die and three SMD components on a 4-layer FR-4 laminate. On Transmit, the FEM covers 2.4 – 2.484 GHz and 5.15 – 5.875 GHz with 4% EVM at +17 dBm output. Receive bands are 2.3 – 2.69 GHz, 3.4 – 3.8 GHz and 5.15 – 5.875 GHz. All receive bands are passive. Through the use of a triplexer filter, switches are eliminated from the 3.4 – 3.8 GHz receive path, achieving a typical insertion loss of 1.5 dB in that band. Design and performance of the key subcomponents are presented, as well as top level FEM performance.