Hotspots of radio galaxies are regions shock-driven particle acceleration. Multiple hotspots have long been identified as potential indicators jet movement or precession. Two frequent explanations describe a secondary hotspot either the location prior termination point, deflected backflow-driven shock: so-called Dentist's Drill and Splatter Spot models. We created high-resolution simulations pr...

Radio spectrum is one of the most scarce and variable resources for wireless communications. Therefore, the proliferation of devices and rapid growth of wireless services continue to strain the limited radio spectrum resource. Cognitive Radio (CR) paradigm is a promising technology to solve the problem of spectrum scarcity. In this paper, a new fair-efficient spectrum sharing scheme is proposed...

Cognitive radio plays a vital role in wireless communication. The cognitive radio composed of a transceiver which is used to check the channel vacancy for communication and avoids busy channels by shifting into unused channel. The scope for spectrum vacancy and area of coverage is increased by using cognitive radio. In cooperative relay network to transmit the primary traffic the primary users ...

Radio local area networks (LAN s) would provide flexible, portable communications within factories and office buildings. Such networks will be required for autonomous vehicles and portable equipment. This paper summarizes the results of extensive radio channel measurements recently made in five operating factory buildings and addresses multiple-access considerations for the design of indoor rad...

Cyber-Physical Systems (CPS) are emerging as a new computing paradigm that combines distributed sensing and actuation. These systems are expected to be deployed in large scale of hundreds to thousands of nodes, which introduces challenges regarding scalability of communication. CPS with high spatial density can lead to low link qualities, high congestion, and ultimately, low packet rate. Resear...

Impulse radio, a form of ultra-wide band signaling, has properties that make it a viable candidate for short range communications in dense multipath environments. This paper describes the characteristics of impulse radio, gives analytical estimates of its multiple access capability, and presents propagation test results and their implications for the design of the radio receiver.

Impulse radio is an ultrawideband system with attractive features for baseband asynchronous multiple-access, multimedia services, and tactical wireless communications. Implemented with analog components, the continuous-time impulse radio multiple-access model utilizes pulse-position modulation and random time-hopping codes to alleviate multipath effects and suppress multiuser interference. We i...

This paper describes overview and definitions about Multiple Input Multiple Output (MIMO) formats which can be used in hybrid Free Space Optics/Radio Frequency (FSO/RF) links. Free space optical links allow obtain high speed data transmission without optical fibers. This type of communication is dependent on weather properties and line of sight is needed. This fact has negative influence on inf...