A two port parametric amplifier has a first port that receives an input signal to be amplified and upconverted and a second port that receives a local oscillator signal. The amplified upconverted input signal is emitted as an output at upper and lower sideband frequencies. The amplifier further has a pair of varactor diodes connected between the first port and the second port. The diodes are connected in parallel from the first port and in series from the second port.