Yakubu S. Baguda

Fuzzy logic partition-based call admission control for mobile WiMAX

The unpredictable nature of the wireless network and exponential growth in traffics with different quality of service requirements has led hardware complexity to escalate. In order to effectively control and manage the network traffics, there is a need for intelligent call admission control (CAC) in admitting traffics into the wireless network that provides necessary quality of service. In this paper, we propose a fuzzy logic partition-based call admission control (FZ CAC). The scheme primarily partitions the total link bandwidth into three which corresponds to constant bit rate (CBR), variable bit rate (VBR) and handover (HO) services. The fuzzy logic admission control scheme was implemented in the HO portion to intelligently keep dropping probability as low as possible based on the available bandwidth. Simulation results showed that the proposed approach outperformed both partition-based CAC (PB CAC) and conventional bandwidth allocation CAC (CB CAC).

Cross layer based biological inspired self-organized routing protocol for wireless sensor network

Currently, the field of wireless sensor networks (WSNs) is becoming increasingly important and a challenging research area. Advancements in sensor networks enable a wide range of environmental monitoring and object tracking applications. Moreover, multihop routing in WSN is affected by new nodes constantly entering or leaving the network. Therefore, nature based self-organized and independent mechanisms are required to tackle problems arising in WSN. The ant inspired routing has shown an excellent performance for WSNs. In this paper, a model of cross layer architecture based self-organized autonomous routing algorithm for WSN and its results are presented. Certain parameters like energy level, link quality and velocity are considered. Energy level and link quality metrics are trade in from physical layer to network layer for discovering an optimal route and also in initialization process. These decisions will come up with the optimal and organized route for WSN.

Assessing routing strategies for cognitive radio sensor networks

Interest in the cognitive radio sensor network (CRSN) paradigm has gradually grown among researchers. This concept seeks to fuse the benefits of dynamic spectrum access into the sensor network, making it a potential player in the next generation (NextGen) network, which is characterized by ubiquity. Notwithstanding its massive potential, little research activity has been dedicated to the network layer. By contrast, we find recent research trends focusing on the physical layer, the link layer and the transport layers. The fact that the cross-layer approach is imperative, due to the resource-constrained nature of CRSNs, can make the design of unique solutions non-trivial in this respect. This paper seeks to explore possible design opportunities with wireless sensor networks (WSNs), cognitive radio ad-hoc networks (CRAHNs) and cross-layer considerations for implementing viable CRSN routing solutions. Additionally, a detailed performance evaluation of WSN routing strategies in a cognitive radio environment is performed to expose research gaps. With this work, we intend to lay a foundation for developing CRSN routing solutions and to establish a basis for future work in this area.

Low Complexity PSO-Based Multi-objective Algorithm for Delay-Constraint Applications

There has been an alarming increase in demand for highly efficient and reliable scheme to ultimately support delay sensitive application and provide the necessary quality of service (QoS) needed. Multimedia applications are very susceptible to delay and its high bandwidth requirement. Consequently, it requires more sophisticated and low complexity algorithm to mitigate the aforementioned problems. In order to strategically select best optimal solution, there is dramatic need for efficient and effective optimization scheme to satisfy different QoS requirements in order to enhance the network performance. Multi-objective particle swarm optimization can be extremely useful and important in delay and mission-critical application. This is primarily due to its simplicity, high convergence and searching capability. In this paper, an optimal parameter selection strategy for time stringent application using particle swarm optimization has been proposed. The experimental result through well-known test functions clearly shows that multi-objective particle swarm optimization algorithm has extremely low computational time and it can be potentially applicable for delay sensitive applications.

Optimizing achievable throughput for cognitive radio network using swarm intelligence

Cognitive radio (CR) technology allows a secondary or cognitive user (CU) to opportunistically access frequency band of a primary user (PU) when it is not in use. However, a CU needs to perform spectrum sensing periodically to avoid causing harmful interference and thereby protecting the quality of service of PUs. A conventional frame structure for CR operation consists of sensing time slot and data transmission time slot which run consecutively. Basically, a longer sensing time produces a higher probability of detection and therefore, better PU protection. However, longer sensing time will reduce the amount of time for data transmission and hence affects the achievable throughput of a CU. In this paper, we study the fundamental tradeoff between sensing time and achievable throughput of the CUs. Based on energy detection scheme, we propose and investigate the feasibility of using Particle Swarm Optimization (PSO) in the design of sensing slot duration to maximize the achievable throughput for CUs for a given frame duration. The results show an encouraging 8.89% increase in throughput with respect to the probability of false alarm, a reduced sensing time by 80% while achieving 97.8% of normalized throughput for CU system with PSO.

Self-optimized autonomous routing protocol for wireless sensor networks with cross layer architecture

Presently, the field of wireless sensor networks (WSNs) is an important and challenging research area. Advancements in sensor networks enable a wide range of environmental monitoring and object tracking applications. Moreover, multihop routing in WSN is affected by new nodes constantly entering or leaving the network. Therefore, nature based self-optimized and independent mechanism is required to tackle problems arise in WSN. The ant inspired routing has shown an excellent performance for WSNs. In this paper, the model of self-optimized autonomous routing algorithm BIOSARP with cross layer architecture for WSN and its results are presented. Certain parameters like energy level, delay and velocity are considered while making decisions. Energy level and velocity metrics are trade in from physical layer to network layer while discovering an optimal route and also in initialization process. These robust decisions will come up with the optimized route for WSN.

Threshold-Based Cross Layer Design for Video Streaming over Lossy Channels

Video applications are highly affected by delay and it eventually requires more effective mechanism to potentially support these applications over wireless channels. Thus, the high demand and need to include different kind of devices with different quality of service (QoS), throughput and heterogeneous terminals with range of capabilities and user preference is very crucial and challenging issue to tackle. In traditional layered approach, all the layers are independent, well defined and designed mainly for specific task. The ability to access multimedia content requires adaptation of media content based on the user interactivity. It is extremely important to provide adequate QoS to support these applications especially in wireless communication media due to the fact that the channel condition changes very rapidly as a result of fading, interference, mobility, handoff and shadowing. There is a dramatic need to bridge the gap between the media content and techniques used to access and deliver increases rapidly. In this paper, we present a basic cross layer design (B-CLD) strategy which adapt with the channel condition and predetermine threshold value. The threshold value has been used to serves as the maximum boundary which the key parameters are compared in order to strategically becides the policy to use. Based on simulation result, the proposed cross layer design scheme outperform non-cross layer design or conventional approach in terms of video quality. More importantly, the delay is relatively low when compared to non CLD approach.

Enhancing Video Quality over IEEE 802.11e WLAN Using Cross Layer Design

The emergence of new multimedia applications with different QoS requirement has lead to serious challenge in maintaining video quality over error-prone transmission environment. However, IEEE 802.11e has been developed to ultimately support delay sensitive application over wireless LAN, but due to high error rate, packet loss, delay and dynamic nature of the environment makes it difficult to achieve the necessary QoS support and requirement. More importantly, with rapid increasing demand for multimedia applications and services, there is dramatic need for more efficient and strategic scheme. Therefore, we proposed a novel cross layer approach using IEEE 802.11e to enhance its capability to effectively support video transmission over wireless LAN. The scheme has been verified and simulated using NS2 simulator.

H264/AVC features & functionalities suitable for wireless video transmission

There has been an alarming increase in demand for multimedia applications due to explosive growth in communication, commerce and entertainment services. Nowadays devices such PDA, laptops and phone have more processing and computing capability. Consequently, this will eventually allow more effective and efficient video streaming and mobile applications over wireless network. Perhaps the development of H.264/AVC has had tremendous impact on the multimedia industry such that it will continue to play an integral role in future and next generation wireless systems due its remarkable features and functionalities which are exceptional. Perhaps it is very important to note that using it alone would not have much profound impact on the video quality unless good parameters and features are selected to enhance the performance. This paper critically examines and explores the features of the H.264/AVC which can significantly improve the perceived video quality in a wireless network. More importantly, the significance of some parameters has been experimented to clearly demonstrate the capability and potential application of H.264/AVC.

Biologically-Inspired Optimal Video Streaming over Wireless LAN

There is dramatic need to achieve optimal performance in wireless multimedia network due to its heterogeneous nature, media content and different quality of service (QoS) requirements from different applications. It is very obvious that supporting multimedia applications and services over wireless is very challenging task, and it requires low complexity and highly efficient scheme to cope with the unpredictable channel condition. In this paper, we develop a biologically-inspired strategy for optimal video streaming application. The optimal parameters configuration selected provide the best QoS settings to enhance the video streaming quality over wireless LAN. The scenario has been simulated in NS-2 environment, it clearly shows that the video quality has been improve by selecting minimum configuration to ultimately support video application. The PSO-based approach outperforms other techniques used to compare the performance of the develop scheme in terms of perceived video quality by more than 0.5dB. The experimental simulation has been used to verify the efficiency and potential application of the PSO in wireless multimedia communication.