Teledyne RF & Microwave's CCM19001 is a Differential Drive Digital QPSK (Quadrature Phase Shift Keying) modulator operating across the 17.0 to 19.0 GHz frequency range. The modulator utilizes differential drive digital inputs (180º apart) to drive both of the bi-phase modulators (mixers) integrated into the assembly. The modulator is a combination of a matched pair bi-phase modulators, which are in quadrature (90º) to each other. It is modulated by switching polarities of the DC voltage controls in 4 different logic states ("0,0", "0,1", "1,0" & "1,1") for 4 phase states. The QPSK modulator provides constant amplitude, 90º vector: 0 (ref.), 90º, 180º, 270º and operates across the -55º to 85º C temperature range.