Load modulated balanced mm-Wave CMOS PA with integrated linearity enhancement for 5G applications

Chandrakanth R. Chappidi, Tushar Sharma, Zheng Liu, Kaushik Sengupta

Research output: Chapter in Book/Report/Conference proceedingConference contribution

35 Scopus citations


The paper presents an mm-Wave load modulated balanced amplifier (LMBA) architecture across 30-40 GHz. The architecture is implemented with a transformer-based hybrid at input and output to allow wideband power combining and achieve high isolation with a control PA for load-modulation and back-off efficiency enhancement across 30-40 GHz. To overcome the compressive behaviour of an LMBA and enhance linearity, an integrated adaptive biasing is integrated on-chip allowing superior ACLR performance across 30-40 GHz. Under CW excitation, the two-stage LMBA demonstrates output power of 18.5-20 dBm, output drain efficiency >30% across 30-40 GHz. The modulation capabilities of LMBA are tested using a 64 QAM signal with a data rate of 6 Gbps wherein PA demonstrates EVM of -26.4 dB and ACLR of -29 dBc at an average output power of 10.6 dBm. To the best of the authors' knowledge, this is the first load-modulated balanced PA at mmWave in silicon.

Original languageEnglish (US)
Title of host publicationIMS 2020 - 2020 IEEE/MTT-S International Microwave Symposium
PublisherInstitute of Electrical and Electronics Engineers Inc.
Number of pages4
ISBN (Electronic)9781728168159
StatePublished - Aug 2020
Externally publishedYes
Event2020 IEEE/MTT-S International Microwave Symposium, IMS 2020 - Virtual, Los Angeles, United States
Duration: Aug 4 2020Aug 6 2020

Publication series

NameIEEE MTT-S International Microwave Symposium Digest
ISSN (Print)0149-645X


Conference2020 IEEE/MTT-S International Microwave Symposium, IMS 2020
Country/TerritoryUnited States
CityVirtual, Los Angeles

All Science Journal Classification (ASJC) codes

  • Radiation
  • Condensed Matter Physics
  • Electrical and Electronic Engineering


  • 5G
  • Hybrid
  • Load modulation
  • Nun-Wave
  • Power amplifier
  • Transformer


Dive into the research topics of 'Load modulated balanced mm-Wave CMOS PA with integrated linearity enhancement for 5G applications'. Together they form a unique fingerprint.

Cite this