A Half-Duplex Self-Protection Jamming Approach for Improving Secrecy of Block Transmissions in Underwater Acoustic Channels

Abstract

Block transmissions are commonly used in underwater acoustic communications due to the large delay spread of the underlying channels. In this paper, we propose a novel jamming protocol based on the half-duplex nature of the underwater transceivers and the block-based transmission structure, taking advantage of the large propagation delays of underwater acoustic channels to create interference at the eavesdropper without affecting the reception of the intended user. This half-duplex jamming protocol acts like a self-protection scheme, which does not need any helpers but instead relies on the legitimate receiver itself to transmit jamming signals for the improvement of secrecy rate. The simulation results evaluate the secrecy rate improvement as a function of the eavesdropper locations.Index Terms-Underwater acoustic communications, halfduplex, jamming, secrecy rate, physical layer security.which the relay was equipped with multiple antennas and proposed a system design for determining the antenna weights and transmit power of the source and relay, so that the system secrecy rate was maximized subject to a total transmit power constraint or the transmit power was minimized subject to a secrecy rate constraint. Further, the work in [5] addressed secure communications considering three cooperative schemes: decode-and-forward (DF), amplify-and-forward (AF), and cooperative jamming (CJ), and aimed at the determination of relay weights and the allocation of transmit power.Recently, using a full-duplex receiver as the jamming source without help from relays has received some attention. In [6], the approach that the full-duplex legitimate receiver could generate artificial noise to jam the eavesdropper was proposed, and the outage secrecy region was used to analyze the secrecy performance from the perspective of geometry. The work in [7] proposed to use both the transmitter and receiver for full duplex beamforming, to improve the throughput and secrecy under the constraint of the guaranteed secrecy and QoS for legitimate users. The joint time and power allocation in fullduplex (FD) wireless-powered communication network was studied in [8], where the average and peak transmit power were constrained to maximize the weighted sum-rate.However, the characteristics of underwater acoustic channels, such as large delay spread, limited acoustic link capacity, and multipath effect have differed the underwater acoustic communication significantly from the ground wireless communication [9], [10]. The approaches aforementioned are neither applicable nor effective to protect the underwater communication information. Until now, most work about underwater communication security is done on the network layer and little attention has been paid on the use of jamming signals to improve the physical layer security.

Maximizing secrecy rate of an orthogonal frequency division multiplexing‐based multihop underwater acoustic sensor network

“…Eavesdropping attacks on UWASNs are studied in References 37 and 38. Specifically, Reference 37 considers a single eavesdropper Eve that attempts to overhear the ongoing communication between the nodes of a UWASN, and computes the success probability of Eve (ie, the probability that Eve can decode what she hears).…”

“…Specifically, Reference 37 considers a single eavesdropper Eve that attempts to overhear the ongoing communication between the nodes of a UWASN, and computes the success probability of Eve (ie, the probability that Eve can decode what she hears). In Reference 38, the authors maximize the SR of a UWA channel that is under threat by a single eavesdropper Eve. Specifically, they suggest that the receiver node transmits a well‐crafted noise‐like signal that combines with transmitter's signal at Eve (which equivocates Eve)—thanks to the large propagation delays of the UWA channel.…”

A secure and energy-efficient opportunistic routing protocol with void avoidance for underwater acoustic sensor networks

“…A comprehensive discussion on the security attacks faced in UASNs is presented in Shahapur and Khanai [25]. A technique to improve the secrecy of block transmissions based on the half-duplex nature of the underwater transceivers in underwater acoustic channels is presented in Huang et al [26]. A few protocols are designed to handle the communication voids in the network [27,28].…”

Maximizing Secrecy Rate of an OFDM-based Multi-hop Underwater Acoustic Sensor Network

“…From a different perspective, there are few more works that deal with the passive eavesdropping attacks in singlehop UWASNs [9], [10]. The work [9] considers a 2-D region (a disk) comprising multiple UWASN nodes (and one Eve node) distributed according to a Poisson point process.…”