Simultaneous Wireless Information and Power Transfer in Cooperative Relay Networks With Rateless Codes

Abstract

This paper investigates the simultaneous wireless information and power transfer (SWIPT) in cooperative relay networks, where a relay harvests energy from the radio frequency (RF) signals transmitted by a source and then uses the harvested energy to assist the information transmission from the source to its destination. Both source and relay transmissions use rateless code, which allows the destination to employ any of the two information receiving strategies, i.e., the mutual information accumulation (IA) and the energy accumulation (EA). The SWIPT-enabled relay employs three different SWIPT receiver architectures, the ideal receiver and two practical receivers (i.e., the power splitting (PS) and the time switch (TS) receivers). Accordingly, three relaying protocols, namely, ideal protocol, PS protocol and TS protocol, are presented. In order to explore the system performance limits with these three protocols, optimization problems are formulated to maximize their achievable information rates.For the ideal protocol, explicit expressions of the optimal solutions are derived. For the PS protocol, a linear-search algorithm is designed to solve the non-convex problems. For the TS protocol, two solving methods are presented. Numerical experiments are carried out to validate our analysis and algorithms, which also show that, with the same SWIPT receiver, the IA-based system outperforms the EA-based system, while with the same information receiving strategy, PS protocol outperforms DRAFT 2 TS protocol. Moreover, compared with conventional non-SWIPT and non-rateless-coded systems, the proposed protocols exhibit considerable performance gains, especially in relatively low signal-to-noise ratio (SNR) regime. Besides, the effects of the source-destination direct link and the relay position on system performance are also discussed, which provides insights on SWIPT-enabled relay systems. Index TermsEnergy harvesting, wireless information and power transfer, cooperative relaying, rateless codes. I. INTRODUCTIONRecently, integrating energy harvesting (EH) technologies into communication networks has attracted much attention [1]-[6], as it provides an effective way to implement green communications and to extend the lifetime of energy-constrained systems, including wireless sensor networks (WSN) and wireless body area networks (WBAN), etc. In EH-enabled communication networks, EH nodes can harvest energy from surrounding environment to power their operations.Apart from the conventional energy sources, e.g., solar, wind and thermoelectric energy, etc, [1]- [3], energy can also be harvested from radio frequency (RF) signals transmitted from other nodes with fixed energy supply such as power gird or high capacity batteries [4]. In [5], it was pointed out that information and energy can be simultaneously received from the RF signals as both energy and information are carried in transmitted RF signals, referred to as simultaneous wireless information and power transfer (SWIPT) [5]- [6]. Compared with conventional EH methods, SWIPT i...

Outage probability of power splitting SWIPT two-way relay networks in Nakagami-m fading

“…Therefore, the outage probability of system can be obtained by substituting (14), (15), and (20) into (13) …”

“…Following these pioneering works, plenty of works have been done for various wireless networks, including cooperative relaying network [12][13][14][15][16], power allocation strategies [17][18][19], resource scheduling [20,21], and multiple-input multiple-out (MIMO) system [22][23][24] or multiple-input single-output (MISO) [25,26]. In [12], the authors analyzed the system maximal throughput for the time switching and power splitting protocols in AF relaying networks.…”

Secrecy in Wireless Information and Power Transfer for One-Way and Two-Way Untrusted Relaying with Friendly Jamming

“…Considering the proactive eavesdropper mode, the optimal solution can be obtained by instituting 1 = 1 and 2 = 2 into (20).…”

“…The authors in [16][17][18] studied SWIPT in relay channels with the goal of minimizing the outage probability by jointly optimizing time assignment ratio and power splitting ratio. The papers [19,20] considered the multirelay cooperative networks where the system throughput and SWIPT with rateless code were studied, respectively.…”

Successful transmission probability of cognitive device-to-device communications underlaying cellular networks in the presence of hardware impairments

“…In recent years, simultaneous information and power transfer (SWIPT) has become a promising technology, which allows a wireless equipment to perform energy harvesting (EH) and information processing at the same time by using the ambient radio frequency signals [1][2][3][4][5][6]. In particular, the work in [7] focused on the analysis of EE in multiple relay orthogonal frequency-division multiplexing (OFDM) systems, equipped with power supplies, so it needs energy harvested from signals transferred by transmitter.…”