On the Unique Channel Identification in Ambient Backscatter Communication Systems

Abstract

Channel coefficient estimation is a challenging problem in ambient backscatter communication systems. In this paper, unique identification of channel coefficients using the Expectation-Maximization (EM) method is investigated. It is proven that the EM method is not able to always yield unique solutions to channel coefficients and therefore the tag symbol estimation accuracy can be compromised. A correct derivation of the hybrid Cramer-Rao Bound (HCRB) is also provided.

Keywords:

• Ambient backscatter communication system
• Channel estimation
• Hybrid Cramer-Rao bound

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Qi Cheng

Qi Cheng obtained the bachelor of engineering degree from Anhui University, China, the master of engineering degree from the Institute of Electronics of the Chinese Academia, and the PhD degree from the University of Melbourne, Australia. He has been a research fellow at the University of Melbourne and taught a wide range of subjects in computer, electrical and telecommunication engineering, and assumed various academic administrative roles, at the Northern Territory University and Western Sydney University, all in Australia. He is currently a Lecturer at the Western Sydney University. Dr Cheng has published more than 40 technical papers in international conferences and journals. He has been TPC members and session chairs of various international conferences.

Ranjith Liyanapathirana

Ranjith Liyanapathirana is a Senior Lecturer in Telecommunications at the School of Engineering, Design and Built Environment, Western Sydney University, Australia. He received BScEng(Hons) degree in electronic and telecommunication engineering from the University of Moratuwa, Sri Lanka and MEng & PhD degrees in electrical engineering from Memorial University, St John's, Canada. His current areas of research interest include wireless sensor networks, biomedical engineering, infrastructure health monitoring and engineering education. He has published over 150 articles in IEEE/IET journals and peer-reviewed conferences. He is a Fellow of the Institution of Engineers (FIEAust), Life Senior Member of IEEE and Senior Member of ACS. E-mail: [email protected]