Secure communication with joint resource allocation, relay and jammer selection in OFDM‐based cooperative networks

Abstract

Summary This paper considers an orthogonal frequency division multiplexing (OFDM) based cooperative network, where a source node communicates with a destination node with the help of multiple intermediate nodes, in the presence of an eavesdropper. Each intermediate node is assumed to be able to act as a relay or a jammer to improve the physical layer security. The problem of joint subcarrier allocation, power allocation, and mode selection to maximize the sum secrecy rate is investigated. We first reformulate the problem of subcarrier allocation and intermediate node mode selection as a three‐sided matching game and propose an algorithm that achieves a stable matching. Then, the sum secrecy rate is further improved by proposing a heuristic algorithm to switch the modes of the intermediate nodes. Finally, an iterative power allocation algorithm is proposed. It is verified by simulation results that the proposed algorithm outperforms various benchmark algorithms such as the equal subcarrier allocation algorithm, the pure relay selection algorithm, and the random relay selection algorithm, especially when the transmit power limit is high and the number of intermediate nodes is large.

A matching‐based context‐aware relay assignment scheme with power control in ad‐hoc wireless networks

“…where HH H is a (L + 1) × (L + 1) random non-negative definite matrix including real and non-negative eigenvalues 𝜈 i s, thus, the capacity can be written as Equation (11).…”

“…Since p c l and p s m are assumed to be integer and the optimization problem contains binary variable 𝛽 m,l , thus, the PT 1 formulation is an MINLP problem. From Equation (11) and Figure 3, it is observed that the capacity function in terms of SUs and DRs power has many local maxima, and the number of local optima usually increases exponentially with the problem dimensions. Some traditional techniques such as branch and bound, and brute-force could be used to reach the optimal solution, whereas they would cause prohibitive computational complexity.…”

“…𝜑 i is the total weight of agents in DRs set, and C s j ,𝜇(s j ) is the capacity as defined in Equation (11). MOS s j 𝜇(s j ) demonstrates the real score ranking from 1 to 5 as will be described shortly, which reflects the FRU received perception quality from lowest to highest levels.…”

“…Optimization solvers are mostly hard in computation that suffer from scalability problems, whereas the running time of stable matching schemes is polynomial. To decrease the complexity of computational, most of the works assume a subset of the joint optimization problems [7][8][9][10][11]. Because the relay selection and channel assignment are naturally combinatorial, matching-based approaches are adopted in some articles [12][13][14][15].…”

Subcarrier‐pair based joint resource allocation for secure cooperative OFDM system with multiple untrusted AF relays

“…Research in ref. [23] considered an OFDM system in the presence of an eavesdropper and used some intermediate node to act as cooperative jammer to improve the security, however, the relay‐aid cooperative jamming scheme were not effective in the presence of untrusted relay. The work in ref.…”