Abstract

The design, fabrication and performance results of a fully monolithic linear vector modulator are described. The circuit is designed for a 5.0 - 5.6 GHz frequency range. The insertion loss of the device is typically 4 dB with input and output return losses better than 7 dB and 15 dB respectively. The RMS amplitude error is typical 0.4 dB and the RMS phase error typical 2.3 degrees over 255 states. These figures can be improved by correcting the systematic amplitude and phase errors of the device by a look-up table. The RMS amplitude error is reduced to 0.2 dB while the RMS phase error is less than 1.2 degrees.