Full-duplex has emerged as a promising technology that enables a communication node to transmit and receive at the same time and same frequency band. One limitation of full-duplex is that the self-interference (SI) is very strong. In this paper, an effective SI cancellation scheme operated in the digital domain is proposed. It is facilitated by the property that the SI channel is reciprocal and the transmitted data is known by both the transmitter and the receiver. It converts the strong SI to the inter-symbol interference through a combination of the signals received in successive time slots. This conversion leads to a reduction in the number of independent signal flows but can be partially compensated for by transmitting more bits using spatial modulation and involving more time slots in the SI cancellation, which enhances the achievable rate. To achieve optimal performance, the transmitted symbols at one node need to be artificially rotated. We also derive a closed-form expression for an upper bound on the average bit error rate, and its error-free information transmission capability is investigated. Monte Carlo simulations over Rayleigh fading channels between two nodes are conducted and advantages are revealed.
Bibliographical noteFunding Information:
Manuscript received August 9, 2016; revised October 2, 2018; accepted October 12, 2018. Date of publication October 30, 2018; date of current version December 10, 2018. This work was supported in part by the National Natural Science Foundation of China under Grant 61622101 and Grant 61571020 and in part by the National Science and Technology Major Project under Grant 2018ZX03001031. The associate editor coordinating the review of this paper and approving it for publication was S. Mukherjee. (Corresponding author: Xiang Cheng.) P. Ju and X. Cheng are with the State Key Laboratory of Advanced Optical Communication Systems and Networks, School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, China (e-mail: firstname.lastname@example.org; email@example.com).
This work was supported in part by the National Natural Science Foundation of China under Grant 61622101 and Grant 61571020 and in part by the National Science and Technology Major Project under Grant 2018ZX03001031.
© 2018 IEEE.
- Full duplex
- multi-input multi-output (MIMO)
- self-interference (SI)
- spatial modulation