Solving for A , antenna area, and replacing A into equation 9; after simplification it yields:. Solving for range R , we obtain the classic radar equation:. All quantities that influence the wave propagation of radar signals were taken into account at this equation. Before we attempt to use the radar equation in the practice for example to determine the efficiency of radar sets, some further considerations are necessary.
The smallest received power that can be detected by the radar is called P E min. Smaller powers than P E min aren't usable since they are lost in the noise of the receiver.
The minimum power is detected at the maximum range R max as seen from the equation. An application of this radar equation is to easily visualize how the performance of the radar sets influences the achieved range. All considerations, when calculating the radar equation, were made assuming that the electromagnetic waves propagate under ideal conditions without disturbing influences. In practice, a number of losses should be considered since they reduce the effectiveness of the radar considerably.
First, the radar equation is extended by including the loss factor L ges. High-frequency components, such as waveguides , filters and also a radome , generate internal losses.
For a given radar set this loss is relatively constant and also easily measured. Atmospheric attenuation and reflections at the Earth's surface are permanent influences. An extended but less frequently used form of the radar equation considers additional terms, like the Earth's surface but does not classify receiver sensitivity and atmospheric absorption.
In this equation, in addition to the already well-known quantities are:. The trigonometric representation shows the influence of the Earth's surface. The Earth plane surrounding radar antenna has a significant impact on the vertical polar diagram.
The combination of the direct and re-reflected ground echo changes the transmitting and receiving patterns of the antenna. This is substantial in the VHF range and decreases with increasing frequency. For the detection of targets at low heights, a reflection at the Earth's surface is necessary.
This is possible only if the ripples of the area within the first Fresnel zone do not exceed the value 0. Sure, he warns you when he is giving you his personal techniques, but you should always follow your primary guidance Aircraft manuals, government regulations, etc.
Please note: Gulfstream Aerospace Corporation has no affiliation or connection whatsoever with this website, and Gulfstream does not review, endorse, or approve any of the content included on the site. As a result, Gulfstream is not responsible or liable for your use of any materials or information obtained from this site. Radar Gain Radar. Eddie sez:. Last revision: Radar Gain. See Also:. Learning never stops. Copyright Code LLC. All Rights Reserved. Turning up the gain increases the amplification of the incoming signal, making weak echoes look stronger, but confusing the display with background speckle or noise, similar to the background crackling of an ordinary radio.
Turning down the gain will reduce the sensitivity of the receiver and reduce the noise, but care must be taken not to overdo as weak or distant echoes can be lost. Save my name, email, and website in this browser for the next time I comment. Marine Gyaan Encyclopedia is a free online resource aims to document all maritime subjects and queries to replace bulky reference books.
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