Cell switching in 6G networks for improved sustainability and handover management

Öz

Sustainability and latency are two critical parameters for future generations of cellular communication networks, such as the sixth generation (6G). Moreover, the "connecting the unconnected" initiative—enabling ubiquitous connectivity—is expected to play a vital role in 6G and beyond networks. In this regard, this work is positioned at the intersection of these concepts. More specifically, network energy consumption is minimized through the application of cell switching concepts, while simultaneously reducing the number of handovers. A mixed-integer programming (MIP) optimization problem was modelled, and a heuristic-based solution algorithm was developed. To address ubiquitous connectivity, high-altitude platform stations (HAPS) are integrated into the network architecture as IMT base stations (i.e., HIBS). The inclusion of HIBSs provides additional capacity for cell switching and traffic offloading purposes, while also enhancing connectivity through their extensive coverage footprints. The efficacy of the developed optimization problem and heuristic-based solution was validated through simulation studies, in which various users, terrestrial base stations, and HIBSs were incorporated into the system modelling. The results confirm that the proposed methodology effectively reduces both energy consumption and the number of handovers, with performance strongly influenced by the handover penalty and the number of users in the network. Overall, the findings suggest that the outcomes of this research can enable more efficient and sustainable industrial operations and management through minimized energy consumption and handovers along with the huge coverage of HIBSs.

Anahtar Kelimeler

• Telecommunications
• 6G Networks
• Sustainability
• Cell switching
• Handover
• Optimization

6G Ağlarında Geliştirilmiş Sürdürülebilirlik ve Hücre Değişimi Yönetimi için Hücre Kapatımı

Öz

Sürdürülebilirlik ve gecikme, altıncı nesil (6G) gibi geleceğin hücresel iletişim ağları için iki kritik parametre olarak öne çıkmaktadır. Ayrıca, "bağlantısızları bağlama" girişimi — her yerde bağlantı sağlama amacı — 6G ve sonrası ağlarda hayati bir rol oynaması beklenen bir konudur. Bu bağlamda, bu çalışma söz konusu kavramların kesişim noktasında konumlanmaktadır. Daha spesifik olarak, hücre kapatma kavramlarının uygulanması yoluyla ağın enerji tüketimi en aza indirilirken, aynı zamanda devir teslim (handover) sayısı da azaltılmaktadır. Bu amaçla, karma tamsayılı programlama (MIP) tabanlı bir optimizasyon problemi modellenmiş ve sezgisel tabanlı bir çözüm algoritması geliştirilmiştir. Her yerde bağlantı hedefini desteklemek için, ağ mimarisine Uluslararası Mobil Telekomünikasyon (IMT) baz istasyonları (yani HIBS – High-Altitude Platform Station-based IMT Base Stations) olarak yüksek irtifa platform istasyonları (HAPS) entegre edilmiştir. HIBS'lerin dahil edilmesi, geniş kapsama alanları sayesinde bağlantıyı artırırken, hücre değiştirme ve trafik boşaltma amacıyla da ek kapasite sağlamaktadır. Geliştirilen optimizasyon problemi ve sezgisel çözüm algoritmasının etkinliği, farklı kullanıcılar, karasal baz istasyonları ve HIBS'lerin dahil edildiği sistem modellemeleri üzerinden gerçekleştirilen simülasyon çalışmaları ile doğrulanmıştır. Sonuçlar, önerilen metodolojinin hem enerji tüketimini hem de devir teslim sayısını etkili bir şekilde azalttığını ve performansın özellikle devir teslim cezası ve ağdaki kullanıcı sayısından önemli ölçüde etkilendiğini göstermektedir. Genel olarak bulgular, bu araştırmanın çıktılarının HIBS'lerin geniş kapsama alanı avantajı ile birlikte enerji tüketimi ve devir teslimlerin en aza indirilmesi yoluyla daha verimli ve sürdürülebilir endüstriyel operasyonlar ve yönetim sağlanmasına katkıda bulunabileceğini ortaya koymaktadır.

Anahtar Kelimeler

• Telekomünikasyon
• 6G Ağları
• Sürdürülebilirlik
• Hücre Değişimi
• Devir Teslim (Handover)
• Optimizasyon

Kaynakça

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