A diplexer-matching dual-band power amplifier LTCC module for IEEE 802.11a/b/g wireless LANs

We have developed a compact dual-band (2.4/5 GHz) power-amplifier module with a concurrent two-stage InGaP/GaAs HBT for triple-mode (IEEE 802.11a/b/g) WLANs. The proposed diplexer-matching network is three-dimensionally implemented in an LTCC substrate (5/spl times/5 mm). The module exhibits an output power of 20 dBm at 2.4 GHz, and 18 dBm at 5.25 GHz with an error vector magnitude of 4-5% for a 54-Mbps OFDM signal. Our approach of using a concurrent dual-band PA reduces the size and cost by almost half compared with using a conventional parallel PA.