Topic
High-frequency direction finding
About: High-frequency direction finding is a research topic. Over the lifetime, 7 publications have been published within this topic receiving 60 citations.
Papers
1 Jan 1966
TL;DR: The principles underlying high-frequency direction finding are summarised and relevant literature is reviewed in this paper, with the principal sources of error including propagation effects, and the statistical problem of combining bearings into a fix are discussed.
Abstract: The principles underlying high-frequency direction finding are summarised and relevant literature is reviewed. Various forms of direction finder are briefly described. The principal sources of error, including propagation effects, and the statistical problem of combining bearings into a fix are discussed. It is generally accepted that improved accuracy is most likely to be obtained with wide-aperture systems, combined with greater use of information about the ionosphere and the propagation modes involved: this view is supported by the literature reviewed.
22 citations
Patent•
27 Sep 1971
TL;DR: In this article, a radio direction finder system incorporating relatively small antennas is provided with a signal processing arrangement for artificially synthesizing variably shaped high frequency direction finding antenna receptivity patterns useful in a first mode for searching for the general location of a broadcasting high frequency transmitter and in a second mode for precisely tracking such a transmitter for navigation purposes.
Abstract: A radio direction finder system incorporating relatively small antennas is provided with a signal processing arrangement for artificially synthesizing variably shaped high frequency direction finding antenna receptivity patterns useful in a first mode for searching for the general location of a broadcasting high frequency transmitter and in a second mode for precisely tracking such a transmitter for navigation purposes.
18 citations
Book•
10 Oct 2012
TL;DR: This research examines the performance of a high frequency direction finding (HFDF) system using structurally integrated (SI) antennas installed on an airborne platform which allows the aircraft structure to become the receiving element.
Abstract: Estimating the angle of arrival (AOA) of a high frequency (HF) signal in the 2-32 MHz band is challenging, especially if the antenna array is installed on a platform with dimensions on the order of one wavelength. Accurate AOA estimates are necessary for search and rescue operations and geolocating RF emitters of interest. This research examines the performance of a high frequency direction finding (HFDF) system using structurally integrated (SI) antennas installed on an airborne platform which allows the aircraft structure to become the receiving element. Two simulated HFDF systems are analyzed at center frequencies of fc = 4 MHz and fc = 11 MHz. The relationship between the number of SI antennas used and the AOA accuracy is examined by simulating systems using NA = 4, NA = 8, and NA = 16 antennas. Simulation is performed using the SI array to synthesize the pattern of a 3loop cube, or vector, antenna. The maximum likelihood algorithm is used to produce AOA estimates. An array of SI antennas, with a dedicated receiver channel for each antenna, produce more accurate AOA estimates at fc = 11 MHz versus fc = 4 MHz. The accuracy improves as NA increases, regardless of center frequency. Linearly combining the outputs of the feed points to match an arbitrary antenna pattern in order to perform AOA estimation is an unnecessary step resulting in a suboptimal array for HFDF purposes.
13 citations
Book•
1 Oct 1996
TL;DR: The story of the development and operation of Huff Duff and its use in combat by the U.S. Navy is described in detail in revealing detail in this article, where the authors reveal that the war against U-boats in the Atlantic was won in part by a high-frequency direction finder that could pinpoint the location of radio transmitters.
Abstract: The war against U-boats in the Atlantic was won in part by a high-frequency direction finder -- called Huff Duff or HF/DF for short -- that could pinpoint the location of radio transmitters. The story of HF/DF's development and operation in combat by the U.S. Navy is told here for the first time in revealing detail.
7 citations
Patent•
3 Jul 1991
6 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2012 | 1 |
| 2000 | 1 |
| 1998 | 1 |
| 1996 | 1 |
| 1991 | 1 |
| 1971 | 1 |