Counter-Intermodulation in the Context of CMOS Outphasing Transmitters

European Microwave Integrated Circuits Conference, pp. 288–291

Abstract

This work presents the design of a CMOS outphasing modulator based on an IQ-modulator topology with passive mixers. The implications from such an architecture on the phase-modulator performance are analysed. Particularly, the problem of counter-intermodulation in the context of outphasing modulation is studied. It is found that the generated distortion is a function of the outphasing angle. Based on the analysis, a 65-nm CMOS prototype is designed and fabricated. Measurements show an ACLR performance of -46.7 dB and -42.5 dB for a 64-QAM modulated signal with a 5MHz and 40MHz bandwidth, respectively.

Authors 3

1. Stefan Mueller Aachen Chair of High Frequency Electronics

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Chair of High Frequency Electronics,Germany

   Chair of High Frequency Electronics, RWTH Aachen University, Germany

2. Oner Hanay Aachen Chair of High Frequency Electronics

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Chair of High Frequency Electronics,Germany

   Chair of High Frequency Electronics, RWTH Aachen University, Germany

3. Renato Negra Aachen Chair of High Frequency Electronics

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Chair of High Frequency Electronics,Germany

   Chair of High Frequency Electronics, RWTH Aachen University, Germany