Hybrid Spectrum Allocation Scheme in Wireless Cellular Networks

Mobile services have seen a major upswing driven by the bandwidth hungry applications thus leading to higher data rate requirements on the wireless networks. Spectrum being the most precious resource in the wireless industry is of keen interest. Various spectrum assignment and frequency reuse schemes have been proposed in literature. However in future networks, dynamic schemes that adapt to spatio-temporal variation in the environment are desired. We thus present a hybrid spectrum assignment scheme which adapts its allocation strategies depending on user distribution in the system. Results show that the proposed dynamic spectrum assignment strategy improves spectrum utilization thereby providing a higher data rate for the users

A survey of self organisation in future cellular networks

This article surveys the literature over the period of the last decade on the emerging field of self organisation as applied to wireless cellular communication networks. Self organisation has been extensively studied and applied in adhoc networks, wireless sensor networks and autonomic computer networks; however in the context of wireless cellular networks, this is the first attempt to put in perspective the various efforts in form of a tutorial/survey. We provide a comprehensive survey of the existing literature, projects and standards in self organising cellular networks. Additionally, we also aim to present a clear understanding of this active research area, identifying a clear taxonomy and guidelines for design of self organising mechanisms. We compare strength and weakness of existing solutions and highlight the key research areas for further development. This paper serves as a guide and a starting point for anyone willing to delve into research on self organisation in wireless cellular communication networks

Hybrid Spectrum Allocation Scheme in Wireless Cellular Networks

Abstract-Mobile services have seen a major upswing driven by the bandwidth hungry applications thus leading to higher data rate requirements on the wireless networks. Spectrum being the most precious resource in the wireless industry is of keen interest. Various spectrum assignment and frequency reuse schemes have been proposed in literature. However in future networks, dynamic schemes that adapt to spatio-temporal variation in the environment are desired. We thus present a hybrid spectrum assignment scheme which adapts its allocation strategies depending on user distribution in the system. Results show that the proposed dynamic spectrum assignment strategy improves spectrum utilization thereby providing a higher data rate for the users

Resource Allocation in Self Organising Cellular Networks.

With the surge in smartphones and tablets, the future of wireless cellular communication systems is marked by a drastic change in user behaviour triggered by the unbridled growth of bandwidth hungry applications. This challenge as well as the limited spectral resources drives the need to further improve resource allocation schemes for cellular networks. This thesis focuses on resource allocation in self organised cellular networks. A distributed self organised channel assignment scheme has been proposed that is shown to achieve perfect orthogonality among neighbouring sectors and reveals the importance of localised rules in designing distributed self organised systems. We define a sectorial neighbourhood based on intercell interference consideration and apply a local coordination among these sectors to achieve a self organised assignment. This unique solution for spectrum assignment strategy is demonstrated as a dynamic spectrum allocation scheme as well as a combination of both the dynamic and static spectrum allocation schemes, verified by system level simulations. The marked improvement in system performance is however not evident for users located at cell edges. Due to the performance of these cell edge users, a self organised fractional frequency reuse scheme whose allocation adapts to the system dynamics is proposed. Current solutions that employ a Fractional Frequency Reuse (FFR) are first analysed to challenge the assumption of fixed cell edge region and power allocation irrespective of the unique user distribution in each cell and its neighbours. We define a unique property for each sector based on its user distribution called its Centre of Gravity (CoG). With the CoG, each sector is classified into states that enables us to apply cellular automata theory that results in a self organised fractional frequency reuse scheme. For mulithop communication links however, intercell interference analysis becomes more complicated due to interference introduced by relay nodes. We finally investigate FFR schemes in multihop communication links comparing the performance of existing FFR schemes in multihop links in terms of their spectral efficiency and area spectral efficiency. A new FFR scheme specifically tailored for multihop links is thus proposed by applying a reuse scheme both in the cell centre and edge regions but rotated at an angle of 120° in the centre region. Furthermore, the sectorial neighbourhood principle introduced earlier is further applied to ensure intercell interference is further minimised

Resource allocation in self organising cellular networks

With the surge in smartphones and tablets, the future of wireless cellular communication systems is marked by a drastic change in user behaviour triggered by the unbridled growth of bandwidth hungry applications. This challenge as well as the limited spectral resources drives the need to further improve resource allocation schemes for cellular networks. This thesis focuses on resource allocation in self organised cellular networks. A distributed self organised channel assignment scheme has been proposed that is shown to achieve perfect orthogonality among neighbouring sectors and reveals the importance of localised rules in designing distributed self organised systems. We define a sectorial neighbourhood based on intercell interference consideration and apply a local coordination among these sectors to achieve a self organised assignment. This unique solution for spectrum assignment strategy is demonstrated as a dynamic spectrum allocation scheme as well as a combination of both the dynamic and static spectrum allocation schemes, verified by system level simulations. The marked improvement in system performance is however not evident for users located at cell edges. Due to the performance of these cell edge users, a self organised fractional frequency reuse scheme whose allocation adapts to the system dynamics is proposed. Current solutions that employ a Fractional Frequency Reuse (FFR) are first analysed to challenge the assumption of fixed cell edge region and power allocation irrespective of the unique user distribution in each cell and its neighbours. We define a unique property for each sector based on its user distribution called its Centre of Gravity (CoG). With the CoG, each sector is classified into states that enables us to apply cellular automata theory that results in a self organised fractional frequency reuse scheme. For mulithop communication links however, intercell interference analysis becomes more complicated due to interference introduced by relay nodes. We finally investigate FFR schemes in multihop communication links comparing the performance of existing FFR schemes in multihop links in terms of their spectral efficiency and area spectral efficiency. A new FFR scheme specifically tailored for multihop links is thus proposed by applying a reuse scheme both in the cell centre and edge regions but rotated at an angle of 1200 in the centre region. Furthermore, the sectorial neighbourhood principle introduced earlier is further applied to ensure intercell interference is further minimised.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Resource Allocation in Self Organising Cellular Networks.

With the surge in smartphones and tablets, the future of wireless cellular communication systems is marked by a drastic change in user behaviour triggered by the unbridled growth of bandwidth hungry applications. This challenge as well as the limited spectral resources drives the need to further improve resource allocation schemes for cellular networks. This thesis focuses on resource allocation in self organised cellular networks. A distributed self organised channel assignment scheme has been proposed that is shown to achieve perfect orthogonality among neighbouring sectors and reveals the importance of localised rules in designing distributed self organised systems. We define a sectorial neighbourhood based on intercell interference consideration and apply a local coordination among these sectors to achieve a self organised assignment. This unique solution for spectrum assignment strategy is demonstrated as a dynamic spectrum allocation scheme as well as a combination of both the dynamic and static spectrum allocation schemes, verified by system level simulations. The marked improvement in system performance is however not evident for users located at cell edges. Due to the performance of these cell edge users, a self organised fractional frequency reuse scheme whose allocation adapts to the system dynamics is proposed. Current solutions that employ a Fractional Frequency Reuse (FFR) are first analysed to challenge the assumption of fixed cell edge region and power allocation irrespective of the unique user distribution in each cell and its neighbours. We define a unique property for each sector based on its user distribution called its Centre of Gravity (CoG). With the CoG, each sector is classified into states that enables us to apply cellular automata theory that results in a self organised fractional frequency reuse scheme. For mulithop communication links however, intercell interference analysis becomes more complicated due to interference introduced by relay nodes. We finally investigate FFR schemes in multihop communication links comparing the performance of existing FFR schemes in multihop links in terms of their spectral efficiency and area spectral efficiency. A new FFR scheme specifically tailored for multihop links is thus proposed by applying a reuse scheme both in the cell centre and edge regions but rotated at an angle of 120° in the centre region. Furthermore, the sectorial neighbourhood principle introduced earlier is further applied to ensure intercell interference is further minimised

Path Loss Models for Low-Power Wide-Area Networks: Experimental Results using LoRa

More and more low-power wide-area networks (LPWANs) are being deployed and planning the gateway locations plays a significant role for the network range, performance and profitability. We choose LoRa as one LPWAN technology and evaluated the accuracy of the Received Signal Strength Indication (RSSI) of different chipsets in a laboratory environment. The results show the chipsets report significantly different RSSI. To estimate the range of a LPWAN beforehand, path loss models have been proposed. Compared to previous work, we evaluated the Longley-Rice Irregular Terrain Model which makes use of real-world elevation data to predict the path loss. To verify the results of that prediction, an extensive measurements campaign in a semi-urban area in Germany has been conducted. The results show that terrain data can increase the prediction accuracy

Business interoperability framework for integrated terrestrial-satellite network

This paper presents a framework for business interoperability with specific focus on the performance indicators and SLA models between terrestrial and satellite operators. It discusses relevant performance metrics currently used in satellite and terrestrial networks as well as the correlation between them and concludes that new KPIs and SLA models as enablers for service delivery over an integrated network are required. We further introduce a framework for criteria comparison on key issues to consider and what could be a bad fit and good fit for the integrated terrestrial-satellite architecture. We believe this guide will also help Virtual Network Operators (VNO) better informed of the opportunities and ease of service delivery over these networks