This paper is a review of amateur-built high-directivity wire antennas, for wireless local area network (WLAN), operating at 2.4-GHz frequency range. Those antennas can be deployed for range extension and interference reduction, for example. Covered in this review are a biquad antenna with reflector, Yagi-Uda antenna, and helical antenna. The distinctive feature of these antennas is their ease ...

The Active Loop Antenna Model ALA100HG is a large aperture antenna designed to provide improved performance compared to traditional active and passive antennas. The ALA100HG has two modes of operation; at Medium and Low Frequencies the antenna is a high efficiency broadband Loop; for High frequencies the antenna has a response similar to a Longwire. The ALA100HG is primarily designed to reduce ...

wire ground systems (120 radials, 0.25 to 0.4 h long, buried 20 cm below the surface of the ground). In spite of the fact that MF radio broadcast services are to some extent (at least in Canada) moving to the VHF band, there is a continuing world wide interest in MF (even LF) antennas, particularly electrically short antennas, perhaps a growing interest as frequencies are vacated by some broadc...

The next generation of low-frequency radio astronomy interferometers will place great demands on the bandwidths of wire antennas. To explore novel antenna designs that meet this challenge, a genetic algorithm has been developed which optimizes the geometry of a given wire template with respect to cascaded noise temperature over the frequency band of operation. The application of this method to ...

this article presents an overview of the recent Frequency dependent and Frequency independent antenna theory. An antenna is defined by Webster’s Dictionary as “a usually metallic device (as a rod or wire) for radiating (transmitting) or receiving radio waves or EM wave.” The IEEE Standard Definitions of Terms for Antennas (IEEE Std 145–1983) defines the antenna as “a means for radiating or rece...

The computer program NEC-2, which calculates the currents on wire-grid models by the method of moments, is modified to analyse structures which consist of a collection of disconnected substructures. The matrix equation for the currents is solved by means of iteration between the substructures using the Siedel method. The convergence is accelerated using an extrapolation technique. For a structu...

Since the first demonstration of wireless technology in 1886 by Heinrich Hertz and its first practical radio application by Guglielmo Marconi in 1901, the antenna has been a key building block in the construction of wireless communications systems. In many instances, the antenna is not considered critical in the initial system design, however, it is the single device that allows RF energy to tr...