A Method of Improving Target Resolution Using Time Diversity and Frequency Diversity

Abstract

The invention provides a method for improving the target resolution by means of time diversity and frequency diversity. The method comprises the following steps: 1 setting a radar transmitted pulse signal as a combination of long pulse and short pulse of different frequency F1 and F2; 2 emitting the radar transmitted pulse signal in different frequency F1 and F2 to realize frequency diversity; 3 receiving the echo, reflected by different targets, of the different frequency F1 and F2, and performing primary processing and storage; 4 using the radar transmitted pulse signal to perform time division radiation in different frequency for the same target in the different frequency F1 and F2, and realizing time diversity; 5 receiving the echo, reflected by means of irradiation to different targets again, of the different frequency F1 and F2, and performing primary processing and storage; 6 obtaining the number of the effective signals for the same target; and 7 performing extraction of the effective target, and acquiring the information of amplitude and time of the effective target. The method for improving the target resolution by means of time diversity and frequency diversity utilizes the frequency diversity and time diversity technology, and can reduce the fluctuating characteristic of the target and can improve the resolution of the target.

Description

technical field [0001] The invention relates to the technical field of surface surveillance radar signal processing, in particular to a method for improving target resolution by using time diversity and frequency diversity. Background technique [0002] With the development of the air transport industry, the scale of airlines is growing day by day, the annual throughput of airports is increasing year by year, and the increase in flight business volume leads to a corresponding increase in ground service vehicles. In airport ground operations, there are inevitably conflicts between aircraft and aircraft, and between aircraft and vehicles, which may cause congestion and confusion in ground traffic, which directly leads to a decline in airport operating efficiency and safety assurance. In addition, the low visibility caused by bad weather such as rain, snow or smog, as well as factors such as building occlusion, complex terrain, and the perspective of the controller will make gr...

AI Technical Summary

Problems solved by technology

Since the principle of the surface surveillance radar is equivalent to that of the primary radar, there is inevitably the problem of multiple reflections and indirect reflections of echoes caused by the complex terrain of the airport. False echoes caused by reflection; in addition, different meteorological conditions, especially severe meteorological conditions such as heavy rain, lead to complex transformation of clutter and introduce more interference, which makes the echo mixed with false echoes caused by various reasons. The target and a large number of clutter signals, the real target signal will have large fluctuations and flickering

[0004] The traditional scene surveillance radar uses a fixed frequency point to scan, so that the target can only be irradiated by a fixed frequency point at any time, the irradiation time is insufficient, and the clutter and false echo components in the echo are complex and difficult to distinguish; the traditional scene Surveillance radar has only one opportunity to scan for any target at any moment. When the antenna rotates and the beam scans, the target needs to wait until the next scanning cycle of the antenna before it can be irradiated. The probability of echo and clutter is relatively high, and it cannot form a cumulative irradiation effect on the target; the false echo caused by a single irradiation of the traditional surface surveillance radar is not easy to be filtered out, especially under severe weather conditions such as heavy rain, the clutter introduced The noise is relatively large, and it is not easy to be filtered out, resulting in large fluctuation characteristics of the target and flickering phenomenon, which brings great difficulties to the correct extraction of the target

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