Combined Human, Antenna Orientation in Elevation Direction and Ground Effect on RSSI in Wireless Sensor Networks

In this paper, we experimentally investigate the combined effect of human, antenna orientation in elevation direction and the ground effect on the Received Signal Strength Indicator (RSSI) parameter in the Wireless Sensor Network (WSN). In experiment, we use MICAz motes and consider different scenarios where antenna of the transmitter node is tilted in elevation direction. The motes were placed on the ground to take into account the ground effect on the RSSI. The effect of one, two and four persons on the RSSI is recorded. For one and two persons, different walking paces e.g. slow, medium and fast pace, are analysed. However, in case of four persons, random movement is carried out between the pair of motes. The experimental results show that some antenna orientation angles have drastic effect on the RSSI, even without any human activity. The fluctuation count and range of RSSI in different scenarios with same walking pace are completely different. Therefore, an efficient human activity algorithm is need that effectively takes into count the antenna elevation and other parameters to accurately detect the human activity in the WSN deployment region.Comment: 10th IEEE International Conference on Frontiers of Information Technology (FIT 12), 201

Uplink Channel Allocation Scheme and QoS Management Mechanism for Cognitive Cellular-Femtocell Networks

Cognitive radio and femtocell are promising technologies which can satisfy the requirements of future mobile communications in terms of dynamic spectrum sharing and high user density areas. Providing quality-of-service (QoS) guaranteed realtime services is challenging issue of future cognitive cellular-femtocell mobile networks. In this paper, we introduce a user’s QoS management mechanism used to protect SINR of macro users from QoS violation caused by femtocell users. We design a novel uplink channel allocation scheme (denoted as “flexible scheme”) for real-time connections. The scheme uses the information of interference level and channel occupancy collected at  cognitive femtocell access points and their covering macro base station (MBS) and apply relevant selection criteria to select an appropriate channel which causes the minimums interference to macro users of the covering MBS. Performance results prove that comparing with femtocell-access-point (FAP)-based and MBS-based uplink channel allocation schemes, the novel “flexible scheme” can provide lower unsuccessful probability of new connection requests

Priority Based Routing for Forest Fire Monitoring in Wireless Sensor Network, Journal of Telecommunications and Information Technology, 2014, nr 3

Recently, forest fire monitoring system in wireless sensor networks has received much attention. The conventional scheme receives fire alert data quickly to inform about fire forest event. However, since two or more nodes may detect a fire, high priority fire detection data frequently collide. In this paper, a new forest fire monitoring system is proposed in order to reduce high priority fire detection data dropped rate, by specifying a high priority received data immediately after fire detection and just before the destruction by fire. Furthermore, the node only transmits high priority data to a node, which has a low possibility of destruction by fire for low end-to-end delay of high priority fire detection data. The simulation results show that proposed scheme can reduce high priority data dropped ratio and the end-to-end delay, and have less effect of wind direction compared with the conventional scheme

Monetary Fair Battery-based Load Hiding Scheme for Multiple Households in Automatic Meter Reading System, Journal of Telecommunications and Information Technology, 2016, nr 1

Automatic Meter Reading (AMR) system is expected to be used for real time load monitoring to optimize power generation and energy efficiency. Recently, it has been a serious problem that user’s lifestyle may be revealed by a tool to estimate consumer’s lifestyle from a real-time load profile. In order to solve this issue, Battery-based Load Hiding ( BLH ) algorithms are proposed to obfuscate an actual load profile by charging and discharging. Although such BLH algorithms have already been studied, it is important to consider multiple households case where one battery is shared among them due to its high cost. In this paper, a monetary fair BLH algorithm for multiple households is proposed. In presented scheme, the core unit calculates the difference between the charged amount and discharged one for each household. If the difference is bigger than the predefined threshold (monetary unfair occurs), the most disadvantageous and advantageous households are given priority to discharge and charge the battery and other households should charge to achieve monetary fairness. The efficiency of the scheme is demonstrated through the computer simulation with a real dataset