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Chaotic antenna array (CAA)s are phased antenna arrays in which individual elements are randomized in their array position, shape, and feed line length. These randomizations generate spatially dependent large scale phase errors (with respect to antenna elements of a uniform array) that enables distinct physical layer security solutions not available to other wireless systems. Herein, a preliminary study on one such novel method, developed to combat eavesdropping is presented. In the proposed method, the CAA equipped transmitter intentionally distorts its signals based on its own array factor (AF) which includes the phase errors. This distortion significantly hampers demodulation at an eavesdropper, while a legitimate receiver that is aware of the phase errors can compensate for the added distortion.
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This content will become publicly available on June 1, 2026
Physical Layer Security Using Joint Directional Modulation and Encoding for Distributed Receivers Serving Chaotic Antenna Arrays
Chaotic antenna arrays (CAAs) are phased antenna arrays with randomized antenna elements exhibiting unique and spatially dependent phase errors. CAAs are promising for generating strong RF fingerprints that can be used for device authentication. For the RF fingerprint to remain secure, it is crucial that the phase errors remain unknown to the user of the CAA. This on the other hand inhibits conventional beam steering that relies on a known antenna array structure. Additionally, the user with the CAA cannot employ known physical layer security methods that are based on phased antenna arrays. To alleviate this issue, we propose a novel security method in networks with distributed receivers. The approach combines i) distortion caused by changes in the array pattern with ii) encoding based on the phase difference at distributed locations, which makes the method resistant against eavesdropping. Mitigating the distortion and decoding the signal becomes only possible if the eavesdropper can obtain all signals received at all legitimate receivers.
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- Award ID(s):
- 2233774
- PAR ID:
- 10658971
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Wireless Communications Letters
- Volume:
- 14
- Issue:
- 6
- ISSN:
- 2162-2337
- Page Range / eLocation ID:
- 1658 to 1662
- Subject(s) / Keyword(s):
- chaotic antenna array, physical layer security, eavesdropping, wireless system, directional modulation, encoding
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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