Micro-Electromechanical impedance control for Electrical Balance Duplexing

Chunqing Zhang, Leo Laughlin, Mark Beach, Kevin Morris, John Haine

Research output: Chapter in Book/Report/Conference proceedingConference Contribution (Conference Proceeding)

155 Downloads (Pure)


The Electrical Balance Duplexer (EBD) implements a form of self-interference cancellation, and can provide high Tx-Rx isolation whilst allowing simultaneous transmit (Tx) and receive (Rx) trough a single antenna in In-Band Full-Duplex (IBFD) radio transceivers. This paper presents a novel Micro-ElectroMechanical Systems (MEMS) based implementation of the tunable balancing impedance component of the EBD. A prototype MEMS tunable impedance demonstrates excellent tuning range and accuracy, and can operate over wide frequency ranges, balancing the EBD at 800 MHz and 1900 MHz to provide >40 dB isolation over a 20 MHz bandwidth. However, the MEMS tunable impedance is observed to introduce non-linear distortion into the system. This non-linearity does not significantly degrade the Tx error vector magnitude, however it has a substantial detrimental impact on the performance of a second stage of linear active cancellation, which achieved just 16 dB of additional cancellation at a Tx power of 23 dBm.
Original languageEnglish
Title of host publicationEuropean Wireless 2016: 22th European Wireless Conference
Subtitle of host publication18-20 May 2016, University of Oulu, Finland
EditorsMarcos Katz
PublisherVDE Verlag
Number of pages6
ISBN (Electronic)9783800742219
Publication statusPublished - 20 May 2016
EventEuropean Wireless 2016; 22th European Wireless Conference. VDE, 2016. - Oulu, Finland
Duration: 18 May 201620 May 2016


ConferenceEuropean Wireless 2016; 22th European Wireless Conference. VDE, 2016.


Dive into the research topics of 'Micro-Electromechanical impedance control for Electrical Balance Duplexing'. Together they form a unique fingerprint.

Cite this