K-means clustering for SAT-AIS data analysis

The paper deals with a problem of automatic identification system (AIS) data analysis, especially eliminating the impact of AIS packet collision and detecting existing outliers in AIS data. To solve this problem, a clustering-based approach is proposed. AIS is a system that supports the exchange of information between vessels about their trajectories, e.g. position, speed or course. However, SAT-AIS, which enables the system to work on a global scale, struggles against packet collisions due to the fact that the satellite, which receives AIS data from ships, has a field of view that covers multiple areas that are not synchronized among themselves. As a result, the received data is difficult to process by AIS receivers, because most of the messages have a character of noise. In this paper, results of a computational experiment using k-means algorithm for packet recovery and for dealing with noise have been presented. The outcome proves that a clustering-based approach could be used as an initial step in AIS packet reconstruction, when the original data is incorrect.

Partial Packets in Wireless Networks: A Review

Data transmission in wireless networks is vulnerable to errors, due to the nature of wireless characteristics. As a result, corrupted packets are a common case in wireless data transmissions. Many techniques have been proposed to tackle these issues and one of the recommended techniques is the partial packet recovery (PPR) scheme. There are various existing PPR methods that have been proposed, in the last two decades, in wireless networks. In addition, recent works have shown the possibility of network coding along with its capabilities in recovering the partial packets. This paper presents a review study of PPR approaches in wireless networks. We classify the approaches into several groups based on the soft information in the PHY layer. Furthermore, we describe the PPR techniques that have used in each of these groups. Our studies found that there are twenty-four protocols have been proposed using PPR to improve the performance in wireless networks.

An Overview of Data Dissemination in Wireless Sensor Network Using an Instantly Decodeable Network Coding

Wireless Sensor Networks (WSNs) are networks of small, cheap, independent battery-powered sensor nodes, finds applications in agriculture, health care, intrusion detection, asset tracking, habitat monitoring and in many other fields. It is sometimes necessary to disseminate data via wireless links after the deployment of sensors so as achieve the objectives of sensors configurations parameters adjustment or distribution of commands management and queries to sensors. The present study considered how Shortest Path Minded Sensor Protocols for Information via Negotiation (SPIN)-Recursive (SPMS-Rec), reduces the energy dissipated in the event of failures by requiring intermediate relay nodes to try alternate routes, is suitable for data dissemination. Despite to the power constraints and memory limitations of sensory nodes, ‘Instantly Decodable Network coding’ (IDNC) was considered because of its practicality, relevance and numerous desirable properties such as instant packet recovery, simple XOR-based packet encoding and decoding, and zero buffer memory to store un-decoded packets. The paper concludes with reference and suggestions of possible future research areas.