Instead of steering an antenna array (in which case we want to receive or transmit primarily in a particularly direction), suppose instead we want to ensure that a minimum of energy goes in particular ...
A weighting method is a means of selecting the weights that multiply the signals from the antennas in an antenna array:
The weights used in the antenna array are fundamental in controlling the beha ...
We'll now derive the most important function in array theory - the Array Factor. Consider a set of N identical antennas oriented in the same direction, each with radiation pattern given by:
Assume ...
Using antenna arrays for diversity reception is one of the most straightforward uses of antenna arrays. Because the power level of a received signal can vary significantly with small changes in distan ...
An antenna array (often called a 'phased array') is a set of 2 or more antennas. The signals from the antennas are combined or processed in order to achieve improved performance over that of a single ...
How do NFC antennas work? This page will discuss that in a simple manner. We'll try to explain why NFC antennas aren't really antennas at all (like the dipole antenna or the Horn Antenna). But first, ...
On this page, we'll discuss the telescope from an antenna theory perspective.
Telescopes aren't really antennas. Antennas are connected to a receiver or transmitter, and collect or transmit radiate ...
Vivaldi antennas are simple planar antennas that are very broadband. The polarization is linear, and the basic antenna structure is shown in Figure 1:
Figure 1. Basic Geometry of a Vivaldi Antenn ...
The world of electromagnetics and radiation is governed by Maxwell's Equations, a set of complicated vector differential equations for determining Electric and Magnetic fields. On this page, we are in ...
To give an idea of the radiated fields from a horn antenna, a specific example will be given. The waveguide dimensions are given by a=3.69 inches, b=1.64 inches, inches, A=30 inches, and B=23.8 inche ...
Introduction to Horn Antennas
Horn antennas are very popular at UHF (300 MHz-3 GHz) and higher frequencies (I've heard of horn antennas operating as high as 140 GHz). Horn antennas often have a dir ...
On the previous page on slotted waveguides, it was shown that for a single waveguide strip, the radiation pattern tends to have a very wide beamwidth in the E-plane and a relatively small beamwidth in ...
The most common slotted waveguide resembles that shown in Figure 1:
Figure 1. Geometry of the most common slotted waveguide antenna.
The front end (the open face at the y=0 in the x-z plane) is ...
Slotted antenna arrays used with waveguides are a popular antenna in navigation, radar and other high-frequency systems. They are simple to fabricate, have low-loss (high efficiency) and radiate linea ...
IFA Basics
The inverted-F antenna is shown in Figure 1. While this antenna appears to be a wire antenna, after some analysis of how this antenna radiates, it is more accurately classified as an ape ...
