A comprehensive survey of wireless body area networks on PHY, MAC, and network layers solutions

Recent advances in microelectronics and integrated circuits, system-on-chip design, wireless communication and intelligent low-power sensors have allowed the realization of a Wireless Body Area Network (WBAN). A WBAN is a collection of low-power, miniaturized, invasive/non-invasive lightweight wireless sensor nodes that monitor the human body functions and the surrounding environment. In addition, it supports a number of innovative and interesting applications such as ubiquitous healthcare, entertainment, interactive gaming, and military applications. In this paper, the fundamental mechanisms of WBAN including architecture and topology, wireless implant communication, low-power Medium Access Control (MAC) and routing protocols are reviewed. A comprehensive study of the proposed technologies for WBAN at Physical (PHY), MAC, and Network layers is presented and many useful solutions are discussed for each layer. Finally, numerous WBAN applications are highlighted

Use of wireless, ad-hoc networks for proximity warning and collision avoidance in surface mines

Despite the record of progress achieved in the United States with respect to reducing fatal and non-fatal injuries in surface mines, both the number and severity of these injuries remain unacceptable. A large fraction of these injuries in surface mines are caused by collisions involving large haulage equipment such as trucks, dozers, and front-end loaders. There are two main contributing factors for these collisions: (i) the massive size of these vehicles, which causes several blind spots surrounding the vehicle for the driver, and (ii) the sheer momentum of these vehicles, which makes it hard to maneuver these vehicles and often necessitates a long response time to avoid collisions. The objective of this work is to investigate the use of different kinds of wireless networks in a distributed ad-hoc mode for providing timely warning about nearby personnel and vehicles, and to evaluate their performance using tests in an actual surface mine.;The contributions of this work are as follows: (i) A zone-based proximity warning system was developed and tested using low power IEEE 802.15.4 radios for detecting obstacles and vehicles at small distances (\u3c10m), with the information of the exact zone they are in, around the vehicle. (ii) For timely warning about approaching vehicles at relatively larger distances (10-100m), a GPS system was integrated with Wi-Fi (IEEE 802.11a/b/p) radios in an ad-hoc mode, where information about approaching vehicles can be known as soon as they come into range. A communication range test was performed in an actual surface mine setting to characterize the distances at which the warnings can be reliably received using each of the IEEE 802.11 family of radios. Both the proximity warning system and the Wi-Fi-based collision avoidance system were evaluated for feasibility at an operating surface coal mine in the southern United States