Extended coverage

Abstract: How well a large wireless sensor network can be monitored or tracked while keeping long live is a challenging problem known as the energy aware coverage preserving. Several coverage solutions have been introduced based on node scheduling and quality coverage. Node scheduling based solutions usually rely on global clock synchronization and/or time delays to resolve conflicts when determining what nodes should be turned-off to save energy. If these time delays cannot be calculated accurately blind areas might emerge jeopardizing the network coverage quality. Other challenges to node scheduling based solutions include finding optimal wakeup strategies that avoid waking up more nodes than necessary; and keeping connectivity and coverage of the network while optimizing the number of nodes. This paper extends the coverage calculation method proposed by Tian and Georganas, referred here as C-PNSS scheme, and describes a novel distributed solution based on local information exchange without the uncertainty of self-schedule algorithms. A Decision algorithm and a new node wakeup scheme were devised to overcome existing problems in actual schemes. We implement our optimal coverage-preserving scheme (OCoPS) as an extension of LEACH. A set of simulation experiments was performed to evaluate OCoPS performance when compared to LEACH and C-PNSS schemes. The results indicate that our solution outperforms C-PNSS by over 20% on network lifetime and by over 25% on network lifetime when the coverage rate is higher than 80%. LEACH is outperformed by nearly over five times on network lifetime. The experimental results also show that our coverage scheme based on our extended coverage calculation method effectively limits the on-duty node number when compared to both LEACH and C-PNSS.

Abstract: This paper considers issues such as residential coverage and achievable bit rate using the Bluetooth personal area network (PAN) standard. Link budget analysis is performed by combining detailed link level physical layer simulations with site specific power predictions from a state-of-the-art indoor propagation model. Assuming a 1 mW transmit unit, coverage plots are generated at 2.4 GHz for an example single and multi-storey residential environment. The investigation considers Bluetooth data medium (DM) and data high (DH) packet types. Results for the transmission of symmetric asynchronous data link (ACL) packets are used to discuss the bit rate capabilities of various time-bounded and non-time bounded Bluetooth enabled consumer electronic devices. To meet the bit rate needs of future consumer electronic devices, QPSK, 16-QAM and 64-QAM are proposed as possible enhancements to the current GFSK mode. Using physical layer simulations, the coverage and data rate performance of these new modes are analysed and compared with those of standard Bluetooth. The use of linear receive architectures and coherent modulation, although adding significantly to the unit cost, is shown to significantly improve radio sensitivity. Results indicate that high bit rate QAM operation is now possible over an extended coverage area.

Abstract: A method, apparatus and system for extending wireless network coverage is generally presented. In this regard, an extender agent is introduced to determine whether a wireless communication(s) was intended for a client(s) on an extended coverage network serviced by a client receiving the communication.

Abstract: An HDTV broadcasting system that uses low-power repeaters arranged in a cellular fashion to extend the service area of a primary advanced TV (ATV) system is described. Examples of ATV extended coverage contours based on DigiCipher high-definition TV (HDTV) measured performance parameters and Federal Communications Commission (FCC) propagation tables are presented. >