A Frequency Translator Using Dual-Gate GaAs FETs

An active 11.5 GHz frequency translator using four dual-gate FETs has been developed. Carrier and spurious sideband suppression of more than 20 dB has been achieved for translation frequency of up to 1 MHz. The same circuit can also be used as a high speed QPSK modulator with phase transition time of about 1 nanosecond.