УДК 621.396

Восстановление радиоизображения, искажённого спектрально-локальными помехами и аппаратной функцией с неизвестными боковыми лепестками

 

А. В. Кокошкин, В. А. Коротков, К. В. Коротков, Е. П. Новичихин

Институт радиотехники и электроники им. В.А. Котельникова РАН, Фрязинский филиал

Статья поступила в редакцию 13 июля 2016 г.

 

Аннотация. В работе показано, что метод перенормировки с ограничением, в отличие от фильтра Винера,  успешно борется со спектрально-локальными помехами и значительно увеличивает качество восстановления изображений, искажённых аппаратной функцией с неизвестными боковыми лепестками.

Ключевые слова: аппаратная функция, неизвестные боковые лепестки, восстановление изображений.

Abstract. In the radio-wave systems there are often situations when the knowledge of the exact shape of the instrumental   function (IF) is impossible. This is especially true for the side lobes (SL) of IF. The following objective factors can be the reason of this situation:

1) design features of antenna systems which do not allow to carry out a sufficiently accurate three-dimensional measurement of the radiation pattern;

2) natural turbulence of the atmosphere, clouds and hydrometeors, causing multipath of the  radio wave propagation.

The absence of the necessary information about the side lobes can lead to significant errors when restoring the image distorted by the IF (Instrumental function).

In this work  we examine the effect of SL AF as the local spectral interference (LPS). It is shown that the renormalization method with restriction, unlike the Wiener filter, successfully fights with the local spectral interference, and significantly increases the quality of image restoration, distorted by the instrumental function with unknown side lobes.

The following conclusions can be drawn from this study:

1. Using the universal reference spectrum (URS) as a sample of the amplitude spectrum of the undistorted image can effectively filter out the spectral - local interference (SLI).

2. Using the method of renormalization limited (MRL) significantly increases the quality of image restoration, distorted by IF with unknown side lobes (SL).

3. Combined image distortion (IF with  unknown SL and SLI) is not an obstacle to the restoration of the image using the MRL.

4. The increase in the amplitude of the SL does not always reduce the quality of image reconstruction using MRL (as opposed to the method of Wiener and methods used in [6-8]).

5. In contrast to other methods , MRL works with obviously more difficult conditions, when the SL energy may exceed the energy of the ML (main lobe) in several times.

Key words: apparatus function, unknown side lobes, image restoration.