The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
An important idea for improving the practical performance of direction finding (DF) systems involves the use of calibration tables. These are generally based on experimental measurements of systemic errors obtained using a known signal to illuminate the antenna. However, the accuracy of the calibration data, and therefore that of the system, is affected by various error mechanisms. This paper uses...
The additional estimation error introduced by the use of finite ground planes is evaluated numerically for two types of conventional direction finding (DF) systems. The analysis reveals that commonly accepted ground plane dimensions result in degraded estimation accuracy when the incoming signals are of unknown polarization.
The polynomial and Pade rational function fitting models were employed to interpolate the scanned wide-angle ARC of radiating element in array environments as spatial dependence. Its efficiency and applicability was also proved in the calculation of mutual coupling between elements in large arrays with sparse samples of scanned ARC. A data compression ratio of 9 has been achieved.
Our work has demonstrated that the Fourier decomposition method to predict mutual coupling between elements in a strongly-coupled array is effective and accurate. In principle, this method is applicable to any type of elements in a large array where the edge effects can be ignored. Further research will be conducted toward developing interpolation method of ARC over phase shift U and V to reduce the...
This paper describes how variations in elevation angle of incoming signals can affect the accuracy of Adcock direction finders (ADFs) in estimating the azimuth direction of arrival (DOA). In accordance with Adve and Sarkar [2000], Maxwellpsilas equations are solved to calculate the mutual coupling characterizing a typical ADF. The voltages at the antenna elements are calculated under several plane-wave...
Tactical ground-based electronic warfare systems have conflicting requirements for wide frequency coverage, good sensitivity and direction finding accuracy, and small size and weight. An experimental multi-band direction finding (DF) antenna was developed to investigate the feasibility of constructing a compact lightweight antenna array by superposing three sub-arrays in the same plane. Experimental...
Direction finding (DF) techniques based on a circular array of monopoles or dipoles have the advantage of being able to provide unambiguous direction of arrival (DOA) estimates over 360 degrees. Of the various implementation approaches that are possible, the Adcock direction finder (ADF) is commonly used at UHF and lower frequency ranges. One of the physical constraints is that the diameter of the...
A Vivaldi TSA array has been designed and analysed. It can operate over 4-16GHz and be capable of scanning to 50deg. This study shows that the strong mutual coupling between elements plays a constructive role in the array performance of active impedance matching. The introduction of corrugated edge to the TSA element has no effect on the active matching but the scan gains are improved. Further research...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.