For a fixed integer k ≥ 0, a k-transmitter is an omnidirectional wireless transmitter with an infinite broadcast range that is able to penetrate up to k “walls”, represented as line segments in the plane. We develop lower and upper bounds for the number of k-transmitters that are necessary, and sometimes sufficient, to cover a given collection of line segments, polygonal chains and polygons.

background: the basic requirements for monitoring anesthetized patients during surgery are assessing cardiac and respiratory function. esophageal stethoscopes have been developed for this purpose, but these devices may not provide clear heart and lung sound due to existence of various noises in operating rooms. in addition, the stethoscope is not applicable for continues monitoring, and it is u...

Wireless designers constantly seek to improve the spectrum efficiency/capacity, coverage of wireless networks, and link reliability. Space-time wireless technology that uses multiple antennas along with appropriate signalling and receiver techniques offers a powerful tool for improving wireless performance Space-time block codes were designed to achieve the maximum diversity order for the given...

This paper investigates a secure wireless-powered multiantenna multicasting system, where multiple power beacons (PBs) supply power to a transmitter in order to establish a reliable communication link with multiple legitimate users in the presence of multiple eavesdroppers. The transmitter has to harvest radio frequency (RF) energy from multiple PBs due to the shortage of embedded power supply ...

Abstract: We evaluate the performance of a multi-beam transmitter system in an indoor environment where a diversity receiver is employed. The system’s performance is evaluated under four new multi-line spot diffusing geometries and is compared with the performance of a single line of diffusing spots and with the conventional diffuse system (CDS). The performance is analysed under the influence ...

A simple technique to estimate the position of a given mobile source inside a building is based on the received signal strength. For this methodology to have a reasonable accuracy, radio visibility of the mobile node by at least three access points is required. To reduce the number of required access points and therefore, to simplify the underlying coverage design problem, a new scheme is prese...

In this paper a novel spatial channel model is developed to provide insight into spatial aspects of multiple antenna communication systems. In particular, we uncouple the antenna configuration and scattering environment effects on the channel matrix, allowing for arbitrary antenna arrays to be studied in a variety environments. We use the underlying physics of free space wave propagation to mod...

FSO Communication is the three dimension global communication system with high bandwidth access. Intersatellite communication can be considered as one of the major robust technology of FSO communication. Investigation of various parameters related to intersatellite OWC can be virtually done by using optisystem software. The performance of the system can also be studied. This paper analyzed the ...

We consider a fading channel in which multiantenna transmitter communicates with multi-antenna receiver through reconfigurable intelligent surface (RIS) that is made of N passive scatterers impaired by phase noise. The beamforming vector at the transmitter, combining receiver, and shifts are optimized order to maximize signal-to-noise-ratio (SNR) receiver. By assuming Rayleigh (or line-of-sight...

Wireless sensor networks are becoming increasingly important in recent years due to their ability to detect and convey real-time in-situ scenes for many civil and military applications. A major technical challenge for a wireless sensor network lies in the energy constraint at each node, which poses a fundamental limit on the network lifetime. We consider two-tiered wireless sensor networks and ...