Outage Probability Analysis and Power Splitter Designs for SWIPT Relaying Systems With Direct Link

Abstract

In this paper, we investigate the outage performance for simultaneous wireless information and power transfer (SWIPT) relaying systems in the presence of direct link between the source and the destination. For the SWIPT relaying system, we employ a power splitter (PS) at the relay, which splits the received signal into the information transmission and the energy harvesting parts. First, we provide an analysis of the outage probability as a closed-form based on a high signal-to-noise ratio approximation. From the analysis, it is recognized that the diversity order of the SWIPT relaying systems equals that of the non-SWIPT cases regardless of the energy harvesting efficiency. The closed-form outage expression also enables us to obtain a simple expression for the PS factor which minimizes the outage probability. Simulation results demonstrate the accuracy of the derived analysis and the efficiency of the proposed PS scheme.

Rate Optimization of Two-Way Relaying with Wireless Information and Power Transfer

“…The abscissa is the normalized distance d 1 /D between S 1 and Q. The results of "Opt" and "Sub (Tool)" are obtained by employing the convex optimization solver YALMIP [37] to find the solution of the joint optimization problem (13)-(16) and the suboptimal problem (17)- (19), respectively, the results of "Sub (Anal)" are obtained with the closed-form solution (24) for the suboptimal problem (17)- (19), and the results of "Equal" are obtained with (θ, δ) = (0.5, 0.5). It should be mentioned that the performance obtained with the analytically derived solution is indistinguishable from that obtained with the convex optimization solver for the suboptimal problem.…”

“…These splitting methods are investigated in cooperative networks with one-way relaying (OWR) protocols [11,[16][17][18][19]24,26] and with two-way relaying (TWR) protocols [12,13,15,23,25]. Here, amplify-and-forward (AF) relays are adopted in [11][12][13]15,24] for a lower complexity with the simple relay operation amplifying the received signal without information decoding, while decode-and-forward (DF) relays are adopted in [16][17][18][19]23,25] for a better performance with the complicated relay operation regenerating the relay signal after decoding the received signal.…”

“…The performance of the PS-SWIPT for the OWR protocol is also studied with a full-duplex DF relay [19] and with the AF relay when the direct link is available [24]. In addition, the optimization of the SWIPT parameters is also studied for the OWR with a DF relay by using statistical information [18].…”

“…In particular, various relaying protocols have been rebuilt to support energy harvesting devices in cooperative networks [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], where relays can be categorized into either energy harvesting nodes or energy transmission nodes. Energy harvesting relays are as low in complexity as communicating devices and harvest the energy in helping the data exchange of the devices in general [11][12][13][14][15][16][17][18][19][23][24][25][26].…”

“…Energy harvesting relays are as low in complexity as communicating devices and harvest the energy in helping the data exchange of the devices in general [11][12][13][14][15][16][17][18][19][23][24][25][26]. On the other hand, energy transmission relays are as highly complex as base stations so that the relays transfer the power and information to the communicating devices [20][21][22]; the relays even employ massive antennas to leverage the efficiency in the power and information transfer at a high cost in implementation [27,28].…”