Ultralow-sidelobe pulse compression method

Abstract

The invention relates to the technical field of digital signal processing, and discloses an ultralow-sidelobe pulse compression method. The method specifically comprises the following steps: S1, a transmitter designs a weighted window function w(t) according to a transmitted linear frequency modulation signal s (t), and converts the transmitted signal into s(t)*w(t); S2, a corresponding pulse compression matched filter h(t) and a corresponding sidelobe suppression filter w(t) are designed at a receiver according to the transmitted signal, wherein the sidelobe suppression filter w(t) is designed according to the weighted window function w(t); S3, the pulse compression result y(t)=[s(t)*w(t)]*[h(t)*w(t)] of an echo signal is calculated according to the matched filter h(t) and the sidelobe suppression filter w(t) at the receiver; S4, the weighted window function at the transmitter is cancelled, an equivalent filter hw(t) is designed at the receiver, and an equivalent filter hw(n) is calculated according to a frequency domain implementation method; and S5, the transmitter transmits the linear frequency modulation signal s(t), the receiver designs a pulse compression equivalent filter hw(n), and ultralow sidelobe is obtained. By adding window functions at the transmitter and the receiver respectively, sidelobe is reduced effectively.

Description

technical field [0001] The invention relates to the technical field of digital signal processing, in particular to an ultra-low sidelobe pulse compression method. Background technique [0002] Surface surveillance radar is a radar that monitors ground moving targets or fixed obstacles such as aircraft and vehicles in the flight area of ​​the airport. It helps the controllers of towers and aprons to clearly understand the positions of ground aircraft and vehicles with the help of surface surveillance radar displays, and provides complex information for airports. The changing situation provides 24 / 7 status awareness. [0003] The surface surveillance radar requires a coverage range of 6km and a distance resolution of 12m. According to the calculation of the radar equation, in order to increase the radar range, it is necessary to increase the radar transmission energy. Wide transmit signal, and the increase of pulse power is limited by the hardware system, and only increasing ...

AI Technical Summary

Problems solved by technology

Weighting the window function can reduce the side lobe, but it will inevitably widen the main lobe, sacrificing a certain range resolution and signal-to-noise ratio. The broadening of the main lobe will reduce the resolution of the radar detection distance, and the loss of signal-to-noise ratio will be reduced. Radar Range

In order to reduce the influence of the sidelobe after matched filtering on the system performance, it is necessary to obtain the optimal amplitude-frequency characteristic function, which can minimize the impact on the distance resolution and signal detection ability while suppressing the sidelobe signal causing interference.

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