Handover failure avoidance in wireless heterogeneous network by using matlab simulation

During the ever emerging network with dense amount of interconnected devices environment, seamless, stable, sustainable and reliable network connection is very crucial in providing the best services to user’s specifically mobile data user. The success rate of mobile users’ handover from current serving cell to another target cell has to be at its optimum. However, with the advancement of this technology of ensuring the trade-off between handover failure and unnecessary handover is taken care of ensuring that only required handover is pursued in order to save the network resource utilization capacity. Hence, there is a need to have better system performance to ensure handover failure is avoided as much as possible. In general, there are several method that can be and has been well research to mitigate the issue on handover failure before which taken into account the RSS measure, time travelling estimation, handover necessity estimation, triggering condition and others. This study aims to enhance the current applied method which use time travelling estimation for a mobile users to stay inside the WLAN coverage area before it is being decided whether to handover or remain connected with the current serving network. The enhancement proposed the increase in overlapping area for a BS and MS to have sufficient time to initiate the handover so that handover failure can be avoided to lower than previous method. Consequently, the system model will compare the result from previous method and this newly proposed measure has improved the total handover failure occurrences by 50%, that every 100 failures from the previous method, this proposed method able to reduce the numbers of handover failure to only 50. However this result does not work with the speed on an MS greater than 30km/h. Hence with this result, it is proposed that for speed higher than 30km/h the same method remains in use to avoid any handover failure to the system

Target Network Selection Algorithm based on Required Dwell Time Estimation

In wireless communication of fourth generation the expectation to integrate a diverse heterogeneous wireless network leads to a worldwide seamless mobility. For seamless mobility in heterogenous wireless networks, selection of best target network from available network is primary goal for handovers. To achieve this goal, we devise a target network selection algorithm to enhance the user satisfaction level.The method relies on a dwell time and prediction of received signal strength. By observing the Predicted received signal strength for a specified dwell time duration, a mobile node is able to decide whether to tigger the handoff process or not. Once the handoff process is triggered. Target network is selected depending upon a cost function. The Simulated results shows that, the proposed algorithm improves the handover performance by measuring the received signal strength accurately. It also selects the optimum target network quantitatively. Therefore, results obtained through our proposed algorithm are more accurate as compared to existing handover algorithms

Predictive and core-network efficient RRC signalling for active state handover in RANs with control/data separation

Frequent handovers (HOs) in dense small cell deployment scenarios could lead to a dramatic increase in signalling overhead. This suggests a paradigm shift towards a signalling conscious cellular architecture with intelligent mobility management. In this direction, a futuristic radio access network with a logical separation between control and data planes has been proposed in research community. It aims to overcome limitations of the conventional architecture by providing high data rate services under the umbrella of a coverage layer in a dual connection mode. This approach enables signalling efficient HO procedures, since the control plane remains unchanged when the users move within the footprint of the same umbrella. Considering this configuration, we propose a core-network efficient radio resource control (RRC) signalling scheme for active state HO and develop an analytical framework to evaluate its signalling load as a function of network density, user mobility and session characteristics. In addition, we propose an intelligent HO prediction scheme with advance resource preparation in order to minimise the HO signalling latency. Numerical and simulation results show promising gains in terms of reduction in HO latency and signalling load as compared with conventional approaches

An Efficient Uplink Multi-Connectivity Scheme for 5G mmWave Control Plane Applications

The millimeter wave (mmWave) frequencies offer the potential of orders of magnitude increases in capacity for next-generation cellular systems. However, links in mmWave networks are susceptible to blockage and may suffer from rapid variations in quality. Connectivity to multiple cells - at mmWave and/or traditional frequencies - is considered essential for robust communication. One of the challenges in supporting multi-connectivity in mmWaves is the requirement for the network to track the direction of each link in addition to its power and timing. To address this challenge, we implement a novel uplink measurement system that, with the joint help of a local coordinator operating in the legacy band, guarantees continuous monitoring of the channel propagation conditions and allows for the design of efficient control plane applications, including handover, beam tracking and initial access. We show that an uplink-based multi-connectivity approach enables less consuming, better performing, faster and more stable cell selection and scheduling decisions with respect to a traditional downlink-based standalone scheme. Moreover, we argue that the presented framework guarantees (i) efficient tracking of the user in the presence of the channel dynamics expected at mmWaves, and (ii) fast reaction to situations in which the primary propagation path is blocked or not available.Comment: Submitted for publication in IEEE Transactions on Wireless Communications (TWC