A 0.05-26 GHz Direct Conversion I/Q Modulator MMIC

Abstract

An integrated I/Q modulator is presented, implementing a static frequency divider for local oscillator (LO) quadrature phase splitting, Gilbert cell switching mixers for direct upconversion, and fabricated in a high speed Indium-Phosphide HBT process. LO quadrature is fine-tuned by a control voltage with 0.18 degrees/mV for 2.14 GHz operation. Single-sideband conversion gain ranges from -14 to -23 dB across the LO frequency range of 50 MHz to 26 GHz. Single-carrier W-CDMA ACPR ranges from -64 dBc to -53 dBc for approximately -20 dBm output power. Output intercept point (OIP3) ranges from +14 dBm at 50 MHz to +4.6 dBm at 26 GHz.