Abstract :
A two bi-directional-way relaying method that enables simultaneous communication without inter-pair interference within two time slots is proposed. A common sensor node B exchanges information with two sensor nodes S1 and S2 via two relaying scenarios. In the first scenario, the relaying system contains two relays, R1 and R2, in two overlapping clusters. In the second scenario, the relaying system has only one relay, R, in the same cluster. Under the amplify-and-forward protocol, the authors propose the use of a pulse amplitude modulation signal, instead of a general complex signal, for presenting informational messages of all sources. The authors then propose a phase-shift transmission scheme. As a result, two-bi-directional relaying transmission is available within two time slots, but without any interference. Simulation results show that in terms of achievable rate, the proposed scheme outperforms the conventional method which uses a general complex signal and four time slots.
Keywords :
amplify and forward communication; protocols; pulse amplitude modulation; relay networks (telecommunication); amplify and forward protocol; bidirectional half duplex relaying scheme; bidirectional relaying transmission; informational message presentation; phase shift transmission scheme; pulse amplitude modulation signal; single user decoder;