A 3 V GaAs MESFET monolithic transmitter for digital/analog dual-mode hand-held phones

A 3 V GaAs monolithic transmitter was developed for digital/analog dual-mod e hand-held phones. The transmitter was designed using a selectively ion-im planted GaAs MESFET library with a gate length of 0.5 mu m. In order to mee t the system requirements, we chose the circuit topology with a highly bala nced LO balun and an image suppressing driver amplifier. The transmitter ac hieves 25.5 dB conversion gain within 824 similar to 849 mHz RF frequency r ange, -40 dBc two-tone (Delta f-442.5 kHz) third-order intermodulation dist ortion (IMD3) at 0 dBm total output power, 5 dBm output 1-dB gain compressi on point, 60 mA current consumption, and 1.5x1.3 mm(2) small chip size. Suc h performances are sufficient enough to be used as a transmitter RF block f or 3 V operating dual-mode hand-held phones.