Balanced FET up-converter for 6 GHz, 64-QAM radio

A 70-MHz to 6-GHz balanced FET converter is described that has a third-order intercept point of 26 dBm, a conversion gain of 3 dB, and 33 dB of local oscillator suppression. Its highly linear performance makes it suitable for 64-QAM radio. Bit error rates (BERs) lower than 10/sup -27/ were measured at the 2.7 dBm RMS (64-QAM) output level. The upconverter shows two advantages compared with a balanced diode converter: (1) a 2-dB intermediate frequency to 6 GHz gain compared with a 6-dB loss; and (2) a higher output level for the same linearity requirement.<>