eprintid: 10186233 rev_number: 9 eprint_status: archive userid: 699 dir: disk0/10/18/62/33 datestamp: 2024-01-30 12:19:03 lastmod: 2024-01-30 12:19:04 status_changed: 2024-01-30 12:19:03 type: article metadata_visibility: show sword_depositor: 699 creators_name: Xu, H creators_name: Wong, KK creators_name: Xu, Y creators_name: Caire, G title: Coding-Enhanced Cooperative Jamming for Secret Communication: The MIMO Case ispublished: inpress divisions: UCL divisions: B04 divisions: C05 divisions: F46 note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher's terms and conditions. abstract: This paper considers a Gaussian multi-input multi-output (MIMO) wiretap channel with a legitimate transmitter, a legitimate receiver (Bob), an eavesdropper (Eve), and a cooperative jammer. All nodes may be equipped with multiple antennas. Traditionally, the jammer transmits Gaussian noise (GN) to enhance the security. However, using this approach, the jamming signal interferes not only with Eve but also with Bob. In this paper, besides the GN strategy, we assume that the jammer can also choose to use the encoded jammer (EJ) strategy, i.e., instead of GN, it transmits a codeword from an appropriate codebook. In certain conditions, the EJ scheme enables Bob to decode the jamming codeword and thus cancel the interference, while Eve remains unable to do so even if it knows all the codebooks. We first derive an inner bound on the system’s secrecy rate under the strong secrecy metric, and then consider the maximization this bound through precoder design in a computationally efficient manner. In the single-input multi-output (SIMO) case, we prove that although non-convex, the power control problems can be optimally solved for both GN and EJ schemes. In the MIMO case, we propose to solve the problems using the matrix simultaneous diagonalization (SD) technique, which requires quite a low computational complexity. Simulation results show that by introducing a cooperative jammer with coding capability, and allowing it to switch between the GN and EJ schemes, a dramatic increase in the secrecy rate can be achieved. In addition, the proposed algorithms can significantly outperform the current state of the art benchmarks in terms of both secrecy rate and computation time. date: 2024-01-17 date_type: published publisher: Institute of Electrical and Electronics Engineers (IEEE) official_url: http://dx.doi.org/10.1109/tcomm.2024.3355308 oa_status: green full_text_type: other language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2215007 doi: 10.1109/TCOMM.2024.3355308 lyricists_name: Wong, Kai-Kit lyricists_name: Xu, Hao lyricists_id: KWONG98 lyricists_id: HXUCX90 actors_name: Wong, Kai-Kit actors_id: KWONG98 actors_role: owner full_text_status: public publication: IEEE Transactions on Communications citation: Xu, H; Wong, KK; Xu, Y; Caire, G; (2024) Coding-Enhanced Cooperative Jamming for Secret Communication: The MIMO Case. IEEE Transactions on Communications 10.1109/TCOMM.2024.3355308 <https://doi.org/10.1109/TCOMM.2024.3355308>. (In press). Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10186233/2/Wong_Coding-Enhanced%20Cooperative%20Jamming%20for%20Secret%20Communication_AAM2.pdf