AffiliationMicrowave Subsystems, Inc.
MetadataShow full item record
RightsCopyright © held by the author; distribution rights International Foundation for Telemetering
Collection InformationProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection.
AbstractThis paper addresses the future military munitions' system requirements for antennas in terms of the existing versus new fabrication technology. The antenna requirements of the future smart munitions will be GPS for precision guidance and TM for system performance testing. The environmental requirements remain the same; large temperature operating range with operation at high temperatures and high shock capable. As usual, the munitions are getting smaller, frequency bandwidth is getting larger, and the cost of the antennas must be minimized in production quantities. In particular this paper compares the existing antenna fabrication technology of Teflon based dielectric printed circuits versus multilayer alumina in the green state, a technology that has been perfected for fabricating microwave integrated circuits (MIC's). The trade-offs that will be addressed are temperature, shock, cost, tunability, loss, size, dielectric constant, and frequency bandwidth. There has been a significant effort to miniaturize the GPS and TM antenna using higher dielectric constant materials. The most popular direction of this effort has been to use ceramic impregnated Teflon. The ultimate temperature performance is the material with a dielectric constant around 2 since this material exhibits a very low coefficient of change with temperature. Materials are available with nominal dielectric constants of 6 and 10 to reduce the size of the antenna but the coefficient of change with temperature is very large and leaves these materials marginal for military temperature ranges. There have also been two other problems with Teflon based printed circuit boards, forming and bonding the boards in a 3D shape and homogeneity of the dielectric constant in the board and after bonding. These problems usually make tuning a requirement and drive the cost of antenna fabrication up. There has been a revolution in MIC's. The circuits are now being made with multiple layers of ceramic (alumina) with interlayer conductive connections and a nominal dielectric constant of 10. The layers are formed in the green state and fired at high temperature and the resulting alumina substrate has a very low coefficient of change with temperature and low loss. Since this procedure is now beyond development, the cost is low and the volume capability is high. Another significant point is that the part can be any shape since the substrate is done in the green state (formable) and then fired.
SponsorsInternational Foundation for Telemetering
Showing items related by title, author, creator and subject.
Contribution assessment of antenna structure and in-gap photocurrent in terahertz radiation of photoconductive antennaZhang, Jitao; Tuo, Mingguang; Liang, Min; Wang, Xiong; Xin, Hao; Univ Arizona, Dept Elect & Comp Engn (AMER INST PHYSICS, 2018-08-07)Photoconductive antenna (PCA) is one of the most widely used terahertz (THz) devices nowadays. Although PCAs have been extensively studied through both theoretical analysis and device design, there still lacks a common agreement upon the mechanism of THz radiation. One of the central questions is how to distinguish and assess the contribution of the antenna structure and in-gap photocurrent to the overall radiation of a PCA. In this work, a three-dimensional full-wave model was first used to quantify the overall far-field radiation of PCAs. The commercial solver (i.e., HFSS) and the Hertzian dipole approximation method were then applied to quantify the far-field radiation solely from the antenna structure and in-gap photocurrent, respectively. The contribution of the antenna structure and in-gap photocurrent can therefore be distinguished by comparing the simulation results among the three methods. The results suggest that, although the THz radiation originates from laser-excited photocurrent within the gap, the overall THz radiation of a PCA is predominated by the antenna structure. As a validation, the cancellation effect was predicated by numerical simulation of coplanar stripline PCA and confirmed with experiment using butterfly shaped stripline PCA. The presented work uncovers the details of the underlying radiation mechanism of the PCA. This could inspire PCA design that aims for engineering the radiation properties of a PCA for specific applications. Published by AIP Publishing.
ANTENNA CONTROL FOR TT&C ANTENNA SYSTEMSKaiser, Julius A.; Herold, Fredrick W.; Fredrick Herold and Associates, Inc. (International Foundation for Telemetering, 2000-10)A thinned array sensor system develops error voltages for steering dish antennas from signals arriving over a broad range of angles, thereby eliminating need for a priori knowledge of signal location.
DESIGN AND APPLICATION OF ANTENNA COUPLERS FOR CERTIFICATION OF AIRBORNE INSTRUMENTATION ANTENNASKujiraoka, Scott R.; Davis, Rick; Naval Air Warfare Center Weapons Division (International Foundation for Telemetering, 1999-10)Instrumentation antennas installed on missiles and airborne targets are required to be tested and certified prior to flight. The antenna coupler is a means of certifying that the antenna is in proper working condition prior to deployment, as damage to the antennas may have occurred during transportation or installation. This coupler also provides a low cost means to evaluate and monitor the antenna throughout the various stages of design and assembly. These antennas can contain arrays for telemetry, beacon tracking, global positioning systems and flight termination. A failure by any one of these arrays could result in the loss of data or improper operation of the flight vehicle. Description of the design and function of antenna couplers will be discussed.