In a half-duplex relaying, the capacity pre-log factor 1/2 is a major drawback in spectral efficiency. This paper proposes a linear precoding/decoding scheme and an alternate relaying protocol in a dual-hop half-duplex system where three relays help the communication between the source and the destination. In our proposed scheme, we consider a phase incoherent method in relays in which the source alternately transmits message signals to the different relays. In addition, we propose a linear interference alignment scheme which can suppress the inter-relay interference resulting from the phase incoherence of relaying. Based on our analysis of degrees of freedom and our simulation results, we show that our proposed scheme achieves additional degrees of freedom compared to the conventional half-duplex relaying.
Bibliographical noteFunding Information:
Manuscript received 29 August 2011; revised 1 March 2012. This research was supported in part by the KCC(Korea Communications Commission), Korea, under the R&D program supervised by the KCA(Korea Communications Agency) (KCA-2011-08913-04002), is funded in part by Korea University and is funded in part by King Abdullah University of Science and Technology. This is an expanded version of work which was presented at the International Conference on Information, Communications, and Signal Processing (ICICS 2011), Singapore, December 2011.
- Relay channel
- alternate transmission
- and phase incoherence
- degrees of freedom
- interference alignment
ASJC Scopus subject areas
- Computer Networks and Communications
- Electrical and Electronic Engineering