saraswathi priyadharshini a
@mitindia.edu
Madras Institute of Technology
Scopus Publications
Scopus Publications
A. Saraswathi Priyadharshini and S. Mary Saira Bhanu
Springer Science and Business Media LLC
A. Saraswathi Priyadharshini and P.T.V. Bhuvaneswari
Wiley
A. Saraswathi Priyadharshini and P. T. V. Bhuvaneswari
Springer Singapore
The adoption of UE-assisted, network-controlled, and hard handover (HO) procedure in LTE-A HetNet imposes several challenges such as performance degradation, complexity in network planning and maintenance. To alleviate these challenges, proper configuration of HO control parameters is needed to trigger the HO procedure in time. The control parameters need to be configured in consideration with various characteristics such as environmental, network, and user equipment (UE). Further, in the literature, analyzing the impact of configuring all the control parameters remains an open issue. Hence, in this work, the impact of control parameters involved in the Macro-Macro environment such as Hysteresis Margin, A3Offset, and Time-To-Trigger have been analyzed. The environmental impact has been analyzed both in urban and in rural scenarios. Also, the dependency of these control parameters with respect to the inter-site distance (ISD) between the base stations and UE mobility pattern is investigated.
Saraswathi Priyadharshini A and Bhuvaneswari P.T.V
Elsevier BV
Abstract In long term evolution - advanced (LTE-A) networks, user assisted and network controlled hard handover (HO) procedure is adopted. In the initial phase of the HO procedure, the transmission of measurement report (MR) is initiated only when the A3 event occurs and persists for the duration of time-to-trigger (TTT). An A3 event is a triggering event which occurs when the signal strength of target evolved NodeB (eNodeB) becomes an offset better than the serving eNodeB. The Hysteresis Margin (HM) and A3Offset (A3Off) are the offset parameters involved in A3 event. Configuration of these parameters plays vital role in HO performance improvement. Most of the configuration methods of these parameters in the literature rely on either optimization rules which is rather complicated for a network of a stochastic nature or on the dynamic characteristics which is not appropriate for the long-term stability of the network. Hence, in this research the cumulative effect of HO control parameters (HCP), such as HM, A3Off and TTT, with respect to inter-site-distance and angle of user equipment movement has been analyzed. From the analysis outcome, a regression based prediction model for HCP configuration has been developed. The presented model outperforms the methods in the literature in terms of serving eNodeB coverage region and HO success region.
A. Saraswathi Priyadharshini and P. T. V. Bhuvaneswari
Springer Science and Business Media LLC
Handover (HO) is the procedure performed to maintain the ongoing session of mobile User Equipment (UE). In Long Term Evolution-Advanced (LTE-A) network, the UE-assisted, network controlled hard HO procedure is suggested by 3GPP. The adoption of the traditional HO mechanism in Heterogeneous Network (HetNet) concept of LTE-A imposes several challenges such as increase in frequent and unnecessary handover rate. This leads to complexity in network planning and maintenance resulting in inefficient resource utilization. Further, the increase in radio link and HO failures are caused due to high-speed UEs. To overcome these challenges, the HO control parameters such as Hysteresis Margin, Cell Specific Offsets, Frequency-Specific Offsets, A3offset and Time-To-Trigger need to be properly configured in consideration with environmental, network and UE characteristics. Hence in this research, an attempt has been made to investigate the impact of these control parameters on HO performance in HetNet environment. Three types of analysis that includes (1) the impact of Inter-Site-Distance, (2) the impact of offloading and (3) the impact of velocity are carried out. The HO performance in terms of HO success rate has been analyzed for Macro–Pico and Pico–Macro scenarios. The results have confirmed that the considered control parameters have a high impact on HO performance.
A. Saraswathi Priyadharshini and P. T. V. Bhuvaneswari
IEEE
Several challenges are imposed by the Heterogeneous Network (HetNet) deployment in Long Term Evolution—Advanced network. Among those, Handover (HO) management plays a vital role in improving the overall network performance. The UE-assisted, network controlled and hard Handover (HO) procedure is adopted in LTE-A which increases the complexity in network planning and maintenance. Proper configuration of control parameters in HO procedure becomes mandatory for successful completion of HO procedure. Hence in this work, an investigation has been made to study the combined impact of the control parameters such as Hysteresis Margin, A3 Offset involved in Macro-Pico environment with respect to Inter-Site Distance (ISD) between the base stations and UEs with random movement.
A. Saraswathi Priyadharshini and P. T. V. Bhuvaneswari
IEEE
Adoption of traditional Handover (HO) procedure in LTE-A HetNet degrades HO performance when compared to the Homogeneous Network. To overcome this, triggering of HO procedure need to be executed in time which is achieved by properly configuring the HO control parameters taking into account the Environmental, Network and User Equipment (UE) characteristics. From the literature survey made, it is found that combined impact of all the control parameters on HO procedure have not been investigated. Hence in this work, an attempt has been made to investigate the combined impact of the control parameters such as Hysteresis Margin, A3Offset, Cell-Specific Offsets and Time-To-Trigger involved in HetNet environment of Macro-Pico deployment. The dependency of these control parameter configuration on HO performance with respect to Inter-Site Distance (ISD) between the base stations, Offloading benefits and UEs with random movement are investigated.
A. Saraswathi Priyadharshini and P. T. V. Bhuvaneswari
IEEE
The adoption of UE-assisted, network controlled and hard Handover (HO) procedure in LTE-A HetNet impose several challenges. It results in tremendous increase in HO failure, frequent and unnecessary HO when compared to Homogeneous Network. To overcome these challenges, the HO procedure need to be triggered in time by proper configuration of HO control parameters in consideration with the Environmental, Network and User Equipment (UE) characteristics. Further, in literature analyzing the combined impact of all the control parameters of HO procedure remains an open issue. Hence in this work, an attempt has been made to investigate the combined impact of the control parameters such as Hysteresis Margin, A3Offset and Time-To-Trigger involved in Macro-Macro environment. The dependency of these control parameter configuration on HO performance with respect to Inter-Site Distance (ISD) between the base stations and UEs with random movement are investigated.
A. Saraswathi Priyadharshini and P. T. V. Bhuvaneswari
IEEE
Network controlled and UE assisted hard Handover (HO) procedure is adopted in 3GPP LTE-Advanced systems. Hysteresis Margin (HM) and A3offset are the major parameters based on which the entering condition of A3event is initiated. In order to mitigate the initiation of HO procedure due to momentary signal fading, persistence of A3event entering condition need to be verified for a period of Time-To-Trigger (TTT). These three parameters are configured by the base station (eNodeB) in the Measurement Configuration (MC) phase. In order to accomplish successful handover (HO), the impact of HM, A3offset along with TTT need to be analyzed. Hence in this research, the above analysis has been extended to different ISD for varying user velocity. From the simulation results obtained, it is found that i) as ISD increases, percentage of A3offset and HM combinations which results in HO success decreases and ii) smaller TTT holds good for larger ISD and vice versa.
P.T.V Bhuvaneswari, S. Indu, N. Lathiffa Shifana, D. Arjun, and A. Saraswathi Priyadharshini
IEEE
Introduction of heterogeneous network concept is a major advancement in LTE and LTE-A. For its implementation in real time, certain modifications need to be done in the existing conventional cell selection scheme. The proposed research concentrates on cell selection mechanism, by developing a dynamic biasing based Cell Range Expansion (CRE) technique for Pico cells. It is based on SINR performance of the UEs and the load existing in the network. In the proposed research, study on mobility of the User Equipment (UE) in a random deployment scenario has been carried out to determine the placement of pico cells within macro cell. Also, the SINR performance, for various transmission power levels have been investigated to compute the coverage range of the pico cells.
S. Gayathri, A. Saraswathi Priyadharshini, and P. T. V. Bhuvaneswari
IEEE
In this paper various activities such as sitting, standing and walking are recognized and classified using multivariate linear regression algorithm. Accuracy of recognition has been found to vary in a free living environment compared to the laboratory conditions. Hence the proposed work has considered free living environment. Zephyr BioHarness which has 3-axis accelerometer sensor is used for data acquisition. The proposed algorithm has been simulated in MATLAB. From the results obtained the accuracy of sitting activity is found to be 99.5 ± 0.3%, for standing activity 99.6 ± 0.4% and for walking activity 96.4 ± 0.2%. This shows more accuracy of 6%,7%,4%for sitting, standing and walking activities with the work taken for comparison.
S Marcia, A. Saraswathi Priyadharshini, R. Meenupriya, and P. T. V. Bhuvaneswari
IEEE
This paper investigates the sensing characteristics of the gas sensor. When Gas Sensor is subjected to ethanol gas, the corresponding analog voltage output is obtained. This analog voltage output is proportional to the concentration of the ethanol gas in the vicinity of the sensor. In order to enhance the accuracy of sensing, various analysis such as range analysis, orientation analysis and concentration analysis are performed. Based on the experimental results obtained, the optimal values for sensing in real time is determined. Further the response and recovery time of gas sensing characteristics is also measured to validate the usage of gas sensor in multi-sensing scenario.
P.T.V. Bhuvaneswari, S. Gayathri, and A. Saraswathi Priyadharshini
IEEE
Estimation of human activities using regression techniques has been performed in this paper. The activities considered for investigation are sitting, standing and walking. As the number of independent variable considered in the proposed work is more than two, Multiple Variate Regression (MVR) technique is applied to estimate the activities. From the performance analysis, it is found that this technique results in an overall accuracy of 99.8% of the activity sitting, 99.85% of the activity standing and 99.95% for the activity walking. However, the process involved in estimation is found to be time consuming. As the process is carried out in real time, in order to reduce the time consumption, the study is extended to Multiple Linear Regression (MLR) technique. From the analysis, it is found that MLR technique yields better result when compared to the MVR technique in terms of time consumption without compromising accuracy.