Accession Number : ADA263998


Title :   Widebanding Techniques for VHF Antennas - II


Descriptive Note : Technical rept. 10 Jan 1992-30 Mar 1993


Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF ELECTRICAL AND COMPUTER ENGINEERING


Personal Author(s) : Thiem, Keem B ; Janaswamy, Ramakrishna


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a263998.pdf


Report Date : Mar 1993


Pagination or Media Count : 141


Abstract : For a variety of mechanical and electrical reasons, the U.S. Army prefers to use a wire antenna for its mobile applications in the HF and VHF bands. However, due to the rapid fluctuation of impedance with frequency, a simple wire antenna is not suitable. This research will look into the aspects of electronic switching of the antenna length and electronic switching of the accompanying tuning network for frequency hopping applications. Two separate schemes will be studied. The first one involves a chosen wire antenna loaded with PIN diodes. The diodes will be selectively switched ON or OFF at different frequencies to control the input impedance of the antenna. In the second scheme, a monopole antenna of fixed length will be considered and data on its input impedance over many sub-bands within 30 to 90 MHz will be generated. Tuning networks composed of resistors, inductors and capacitors will be designed over each sub-band. The various networks will then be connected via PIN diodes and selectively switched to provide matching over a much wider band.


Descriptors :   *COMPUTER AIDED DESIGN , *ANTENNAS , *PIN DIODES , *ELECTRONIC SWITCHING , *ANTENNA CONFIGURATIONS , COMPUTER PROGRAMS , DIODES , FREQUENCY , TUNING , MONOPOLE ANTENNAS , RESISTORS , INDUCTORS , CAPACITORS , VERY HIGH FREQUENCY , SWITCHING , IMPEDANCE , LENGTH , NETWORKS , INPUT , HIGH FREQUENCY


Subject Categories : Electrical and Electronic Equipment
      Computer Programming and Software


Distribution Statement : APPROVED FOR PUBLIC RELEASE