The propagation of ultra wide band (UWB) signals through walls is analyzed. For this propagation studies, it is necessary to consider not only propagation at a single frequency but in the whole band. The UWB radar output signal is formed by both transmitter and antenna. The effects of antenna receiving and transmitting responses for various antenna types (such as small and aperture antennas) ar...

The use of directional antenna in wireless ad hoc networks largely reduces radio interference, thereby improving the utilization of wireless medium and consequently the network throughput, as compared to omnidirectional antenna, where nodes in the vicinity of communication are kept silent. In this context, researchers usually assume that the gain of directional antennas is equal to the gain of ...

The radiation field from a transmitting antenna is characterized by the complex Poynting vector E x H* in which E is the electric field and H is the magnetic field. Close to the antenna the Poynting vector is imaginary (reactive) and (E,H) decay more rapidly than 1/r, while further away it is real (radiating) and (E,H) decay as 1/r . These two types of fields dominate in different regions in sp...

The radiation field from a transmitting antenna is characterized by the complex Poynting vector E x H* in which E is the electric field and H is the magnetic field. Close to the antenna the Poynting vector is imaginary (reactive) and (E,H) decay more rapidly than 1/r, while further away it is real (radiating) and (E,H) decay as 1/r . These two types of fields dominate in different regions in sp...

It is very common that when a broadcaster needs to install an FM transmitting antenna within a large metropolitan area he places it on the tallest structure or building available. When the rooftop is already occupied by a large number of other types of transmitting and receiving antennas, the panel dipole antenna should be chosen. This antenna is secured to the side walls of the upper floors wi...

This paper presents an analysis of the channel capacity for 2×2 multiple input multiple output (MIMO) antenna systems. In this research, channel capacity is simultaneously analyzed by arbitrary transmitting (Tx) and receiving (Rx) antenna correlation matrix with correlated fading channel matrix. The channel capacity for 2×2 MIMO system is calculated. Considered parameters include receiving sign...

Multiple-input multiple-output (MIMO) are used in wireless communications to achieve high data rates within the limited frequency spectrum. MIMO uses multiple transmitting and receiving antennas so as to utilize the advantages of spatial diversity. The performance analysis of MIMO system over AWGN and Rician fading channels using OSTBC4 as space time coding with Zero Forcing (ZF) receiver is pr...

0278-6648/03/$17.00 © 2003 IEEE IEEE POTENTIALS Antenna arrays are individual radiating elements combined so that they function and perform like a single large antenna. Besides high radiating beam directionality, antenna arrays offer the capability to scan the main beam and control sidelobe radiation elect r o n i c a l l y . Retrodirective antenna arrays, as the name suggests, have a special f...

In recent years, wireless communication technology has been studied intensively. In particular, MIMO which employs several transmit and receive antennas is a key technology for enhancing spectral efficiency. However, conventional MIMO architectures require some transceiver circuits for the sake of transmitting and receiving separate signals, which incurs the cost of one RF front-end per antenna...

The viability of a radiofrequency (RF) telemetry channel for reporting individual neuron activity wirelessly from an embedded antenna to an external receiver is determined. Comparing the power at the transmitting antenna required for the desired Channel Capacity, to the maximum power that this antenna can dissipate in the body without altering or damaging surrounding tissue reveals the severe p...