A Full Duplex RF Front End Employing an Electrical Balanced Duplexer and a Chebyshev Load-Balancing Filter

Dror Regev*, Itamar Melamed, Nimrod Ginzberg, Emanuel Cohen

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

Abstract

This paper presents a new Chebyshev load-balance (LB) circuit for electrical-balanced RF front-ends targeted for simultaneous transmit-receive (STR) operation. TX reflection of a commercial Wi-Fi antenna with near 3:1 VSWR and direct TX leakage of a commercial quadrature-hybrid are considered and cancelled concurrently in simulations and measurements. We analyze the reflective LB as the RF front-end optimal load and propose a theoretically lossless impedance-matching network that achieves self-interference cancellation (SIC) over more than ± 5 % bandwidth relative to the carrier. A PCB design with two transmission lines and lumped RLC elements is realized to demonstrate the potential of the architecture, achieving > 25 dB of total TX-RX isolation over 300 MHz around 2.65 GHz where the antenna reflection is 7 dBr. This is the first published work that reports cancellation of such a reflective antenna employing a low-cost LB circuit. The proposed Chebyshev LB is theoretically superior to the networks proposed in previous papers.

Original languageEnglish
Title of host publication2023 IEEE/MTT-S International Microwave Symposium, IMS 2023
PublisherInstitute of Electrical and Electronics Engineers Inc.
Pages378-381
Number of pages4
ISBN (Electronic)9798350347647
DOIs
StatePublished - 2023
Externally publishedYes
Event2023 IEEE/MTT-S International Microwave Symposium, IMS 2023 - San Diego, United States
Duration: 11 Jun 202316 Jun 2023

Publication series

NameIEEE MTT-S International Microwave Symposium Digest
Volume2023-June
ISSN (Print)0149-645X

Conference

Conference2023 IEEE/MTT-S International Microwave Symposium, IMS 2023
Country/TerritoryUnited States
CitySan Diego
Period11/06/2316/06/23

Keywords

  • duplexer
  • electrical-balance (EB)
  • full-duplex (FD)
  • impedance matching
  • self-interference cancellation (SIC)
  • simultaneous transmit receive (STR)
  • transmitter leakage

Fingerprint

Dive into the research topics of 'A Full Duplex RF Front End Employing an Electrical Balanced Duplexer and a Chebyshev Load-Balancing Filter'. Together they form a unique fingerprint.

Cite this