Siemens-albis, Ag

Albert Schenkel

Urs Leuenberger

Pierino Pacozzi

Rolf Baechtiger

A method for correction errors in radar systems that operate using a crossfeed principle (CFR), in which echo signals are directly received from flying objects, such as an aircraft. In particular, the present invention is used in connection with low-flying objects, in which radar signals are indirectly reflected from the surface of the earth to an antenna of the radar system. Correction terms are determined and weighted, using correction factors, so as to improve the capability of the crossfeed radar system to accurately determine the exact elevation of the flying object. The correction factors that are used to improve the accuracy of the radar system are based upon sea state numbers, or Beaufort numbers, which vary in relation to the shape and/or structure of the reflecting surface.

Correcting errors in crossfeed radar systems

Radar systems that operate in accordance with the crossfeed method require an exact balancing of the individual Doppler frequency evaluation channels in the receiver. According to the invention, a special method is used first to make the amplitude levels in the individual channels equal to one another and then to determine and balance the phase differences between the channels. A radar system using this method is also described.

Method for balancing channels in a multichannel pulse radar system and a

Radar tracking or homing units employing three or more primary radiators and utilizing an arrangement of a sum-difference network and signal processing stage to form sum, difference and cross-related or cross-term signals and to effect correction of errors introduced due to the presence or apparent presence of two targets with the resolvable radar volume, using a stipulated method of signal processing.

Method of and apparatus for angular measurement in target tracking radar

An arrangement for correcting deviations from the true bearing due to the effects of specular reflecting surfaces in target tracking radar installations having at least three primary feeds. At least two of the primary feeds are aligned such that a plane formed by the longitudinal axes of their radiation characteristics is disposed at least approximately perpendicular to the specular reflecting surface. At least one further primary feed is arranged such that the longitudinal axis of its radiation characteristic is located externally of such plane. A summation-difference network produces from the echo signals received by the primary feeds, apart from a summation signal, also two difference signals, and a cross-term signal formed in at least one measurement interval. From these signals there is produced an angle error signal which is divided into two components. In a signal processing stage there is obtained a correction signal in order to correct the angle error signal falsified by the specular reflection effects.

Growing community of inventors

Zurich, Switzerland

Albert Schenkel