Zorlu Hava Koşulları Altında Yer İstasyonu Seçimi Yoluyla Optik HAPS İletişiminde Gizlilik Başarımının Arttırılması

Yıl 2025, Cilt: 2 Sayı: 1, 1 - 10, 28.03.2025

Eylem Erdoğan , Evla Safahan Ahrazoglu , Emre Berker Bakırcı , İbrahim Altunbaş

Öz

Son zamanlarda, havasal iletimlerde bilginin ele geçirilebilmesi nedeniyle, karasal olmayan ağların (non-terrestrial networks, NTNs) fiziksel katman güvenliği hem akademide hem de endüstride artan bir ilgiyle karşılanmaktadır; özellikle de yetkisiz bir kullanıcının vericiye veya alıcıya yakın bir konumda bulunması durumunda güvenlik riskleri artmaktadır. Olası güvenlik açıklarını ele almak amacıyla, bu çalışmada optik haberleşme kullanan bir yüksek irtifa platform istasyonu (high altitude platform station, HAPS) sisteminin gizlilik performansı, bir gizli dinleyicinin varlığı altında incelenmiştir. Özellikle, kesinti ve ele geçirilme olasılıklarını dikkate alarak önerilen sistemin gizlilik-güvenilirlik dengesi değerlendirilmiş ve gizlilik kesinti olasılığı hesaplanmıştır. Önerilen senaryoda, HAPS’ın farklı yüksekliklerde konumlanmış birden fazla yer istasyonu ile iletişim kurduğu pratik bir durumu ele alarak, sistemde sis, bulutlar ve hava kirliliği gibi farklı zayıflatıcı etmenlerin etkisi incelenmiştir. Sonuçlar, hava koşullarının optik HAPS iletişimlerinin gizlilik performansını önemli ölçüde etkilediğini göstermektedir. Ancak, yer istasyonlarının daha yüksek irtifalarda konumlandırılması veya birden fazla yer istasyonu arasından seçim yapılması sistemin genel güvenlik performansını arttırabilmektedir.

Anahtar Kelimeler

HAPS sistemleri, optik haberleşme, fiziksel katman güvenlik

Improving Secrecy Performance in Optical HAPS Communications Through Site Selection Under Harsh Weather Conditions

Öz

The physical layer security of non-terrestrial networks (NTNs) has recently garnered increasing attention from both academia and industry as the information can be intercepted in aerial transmissions, especially when an illegitimate user positions itself near the transmitter or receiver. To address this vulnerability, we investigate the secrecy performance of a high altitude platform station (HAPS) system using optical communications in the presence of an aircraft eavesdropper. Specifically, we assess the secrecy-reliability trade-off by considering both outage and interception probability, and explore the secrecy outage probability. In the proposed setup, we evaluate a practical scenario in which the HAPS communicates with multiple ground stations located at different altitudes, examining the system’s physical layer security performance for different types of attenuators including fog, clouds and air pollution. The findings indicate that weather conditions significantly affect the secrecy performance of optical HAPS communications. However, placing ground stations at higher altitudes or selection among multiple ground stations can improve the overall security performance of the system.

Anahtar Kelimeler

HAPS systems, optical communication, physical layer security

Kaynakça

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