Single-chip Dual-Mode Power Amplifier MMIC using GaAs E-pHEMT for WiMAX/WLAN Applications

A single-chip dual-mode power amplifier monolithic microwave integrated circuit (MMIC) operating at 5 V single supply has been developed for both WLAN 2.45 GHz IEEE 802.11lb/g and WiMAX 3.5 GHz IEEE 802.16d WiMAX standards applications. The PA MMIC utilizes the GaAs E-pHEMT process (enhancement-mode pseudomorphic high electron-mobility transistor) of WINs Corp.. The PldB of dual-mode power amplifier are 30 dBm at 3.5 GHz and 27 dBm at 2.45 GHz. In WiMAX mode, under WiMAX IEEE 802.16-2004 OFDM modulation the EVM(error vector magnitude) is 2.7% at 24.4 dBm Pout with 25.6 dB of gain and over 15% of PAE (power added efficiency). In WLAN IEEE 802.11g mode, under OFDM 64 QAM/54 Mbps modulated signal the PA is 2.5% of EVM at 19 dBm Pout with 21 dB of gain. The dual-mode PA chip is implemented as a two-stage structure integrated with broad-band input-matching and inter-stage matching networks and external dual-band output-matching network.