Optical nanoantennas have been studied as a means to manipulate nanoscale fields, local field enhancements, radiative rates, and emissive directional control. However, a fundamental function of antennas, the transfer of power between a coupled load and far-field radiation, has seen limited development in optical antennas owing largely to the inherent challenges of extracting impedance parameter...

The recent research has proved that the Multiple-input-multiple-output (MIMO) systems can substantially increase the channel capacity by employing multiple antennas at both the transmitter and receiver, without increasing either transmitter power or bandwidth. Hence it is very much essential to know all the aspects of MIMO system. Usually, in any MIMO system the antenna design plays a major rol...

Laboratory testing of digital beamforming processor is required to test and optimize the beamformer algorithm, code and hardware before integrating with antenna and testing the beamformer in an anechoic chamber. Development of a stimulus generator, for carrying out such an exercise, itself can be quite an involved task for a digital beamformer employing a large phased array antenna. This paper ...

We introduce an opportunistic scheduling to enhance the physical layer security with transmit antenna selection (TAS) in multiuser environment. We consider a wireless communication system composed of a single transmitter and multiple legitimate users in the presence of several eavesdroppers with each node having multiple antennas under quasi-static Rayleigh fading channel. The transmitter selec...

A multiple-input multiple-output (MIMO) system for trans-horizon radio communications within the high-frequency (HF) band (3 to 30 MHz) is presented. The diversity of transmitted polarizations is proposed as an alternative to spatial diversity in order to limit the aperture of antenna arrays at both ends of the radio link. In a theoretical step providing the estimation of capacity gain for diff...

This paper represents a study of simulation of a Dielectric Resonator Antenna (DRA) based on its rectangular shape for Artificial Neural Network (ANN). The DRA is intended to be used as the radiating element of a transmitting array of active integrated antennas; its input impedance must exhibit a proper resistive load at the fundamental resonance frequency, as well as a dominant reactive behavi...

The enhanced Loran signal transmits the through atmospheric channel. Considering obstacles and other factors, radio wave will be affected by path loss, shadow fading multipath fading. Therefore, power at different distances from transmitting point is different. scaled model antenna used to transmit receive signal, receiver receive. According of received receiver, propagation distance can deduce...

A simple propagation model for the VHF and UHF bands is presented. The model is a computational form of the data provided by the FCC F(50,50) propagation curves, and it is aimed to be used by practicing engineers. It allows the estimation of median path loss, received power, or electrical field strength which usually is sufficient in many practical applications. The model is independent of freq...

Recently, space-division multiple-access (SDMA) schemes [1], [2] have been proposed to increase the capacity of wireless communication systems by simultaneously transmitting and receiving multiple co-channel signals through different spatial channels. In this paper, we address the uplink (remote users to the base station antenna array) blind channel and sequence identification problem for an SD...

rr HE AEROVOX RESEARCH WORKER for July, 1949 contained a discussion of the fundamental properties of the half -wave dipole antenna and defined three basic configurations in which multiple dipoles are used to obtain desirable directional effects in transmitting or receiving radio signals. These arrangements included; collinear dipoles, broadside dipoles, and end -fire dipoles of both the driven ...