Joint Power Allocation and Strategy Selection for Half-Duplex Relay System

Abstract

Decode-and-Forward (DF) and Compress-andForward (CF) are two efficient cooperation strategies for relay networks. Combination of DF and CF strategies is promising to improve the achievable rate of cooperative communication systems. To thoroughly aggregate the advantage of DF and CF strategies, we put forward a joint Power Allocation and Strategy Selection (PASS) scheme for half-duplex relay channel. The PASS scheme is shown to achieve a higher rate compared with regular hybrid DF/CF scheme. The rate gain obtained in the static relay channel results from actively adjusting and optimizing the relay power followed by selecting the better strategy between DF and CF. Particularly, when the relay receives and transmits in sequential time slots, we characterize the positive rate improvement area of PASS scheme analytically and give a near optimal setting for approaching the best rate performance. The PASS scheme is extended to fading relay channels. We show that the rate increment obtained from the PASS scheme is further magnified by employing an advanced relay power allocation technique over channel states. The corresponding optimal power allocation is established based on the concavity of the rate achieved by the PASS scheme in static relay channel. Numerical results are presented to validate the analysis.

A Comprehensive Survey on Cooperative Relaying and Jamming Strategies for Physical Layer Security

“…Based on the transmission and reception capability, there are two types of relays: half-duplex (HD) relays [51], [52], [53] and full-duplex (FD) relays [54], [55], [56]. A HD relay needs two orthogonal channel uses to transmit and receive information, whereas a FD relay can simultaneously transmit and receive information, allowing the spectrum to be more efficiently utilized.…”

Parallelised relaying protocol with opportunistic priority assignment for enhanced spectral efficiency in cross‐relay interference

“…Therefore, the relaying system has been considered as one of the core technologies for the fifth generation cellular mobile communications [3], and its applications can be extended to device‐to‐device [4], vehicle‐to‐everything [5], and internet of things [6]. In order to improve the spectral efficiency, various conventional relaying schemes have been investigated [7–11]. In [7–10], several different approaches have been proposed for optimal power allocation with channel state information (CSI) between the source and the relay to maximise the signal‐to‐noise ratio (SNR).…”

“…In order to improve the spectral efficiency, various conventional relaying schemes have been investigated [7–11]. In [7–10], several different approaches have been proposed for optimal power allocation with channel state information (CSI) between the source and the relay to maximise the signal‐to‐noise ratio (SNR). In [11], an opportunistic relay selection scheme was proposed to improve the data rate.…”

Inter-Relay Interference Mitigation for Chirp-Based Two-Path Successive Relaying Protocol

“…In the cooperative relay schemes, there are two main issues: relay power allocation and relay selection [12]. In the relay power allocation technique, since the relay power controls not only the transmission coverage but also the transmission performance, various research has been done to optimize the relaying power [13,14]. In the relay selection technique, since a wireless channel environment is randomly fluctuated, an opportunistic relay selection (ORS) protocol that selects the optimal relay among multiple relays based on channel state has been proposed [15].…”