Digital lightning detection method and device thereof

Abstract

The invention relates to a digital lightning detection method and a device thereof. The method comprises the following steps: receiving an electromagnetic signal generated when cloud-to-ground flash lightning discharging to generate an electric detection signal; digitalizing the conditioned electric detection signal; filtering the digital signal; establishing a uniform time scale; establishing a lightning signal identification criterion and a digitized cloud-to-ground flash lightning signal identification model by a time determination method, a bipolar test method and a homopolar test method by considering transmission features of a lightning electromagnetic radiation waveform; establishing a time window preprocessing area, and acquiring a development trend of the input digital signal and the corresponding typical parameters; and computing and determining the parameters of the input digital signal in combination with data in the time window by the digitized cloud-to-ground flash lightning signal identification model . The device consists of an antenna, a signal conditioner, an analog to digital converter, a module of cloud-to-ground flash lightning signal identification model, a system control manager, an assistant control manager, a communication interface, an external memory and a clock.

Description

technical field [0001] The invention belongs to the field of lightning detection, and relates to a lightning detection method and a device thereof, in particular to a digital lightning detection method and a device thereof. It is a digital lightning detection method and device based on digital signal processing and capable of flexible adjustment. It is suitable for lightning detection in a large area. Background technique [0002] As we all know, when lightning occurs, powerful sound, light, and electrical signals will be generated. Due to their own characteristics, the sound and light signals have a short range and are not suitable for long-distance large-area lightning detection. However, the electromagnetic radiation field generated by lightning activities, especially the electromagnetic radiation field in the low frequency / very low frequency band where the main energy is concentrated, the electromagnetic radiation waves generated by it can travel hundreds of kilometers ...

AI Technical Summary

Problems solved by technology

Its shortcomings are: 1. It is difficult to realize when the criterion is complicated, and the discrimination rate of cloud flash and ground lightning is relatively low. In the detection system that only accepts ground lightning, it may also affect the detection efficiency; 2. After the circuit design is finalized, lightning The signal recognition model is inconvenient to change or adjust according to the change of usage conditions, resulting in the loss of some real lightning signals that do not meet the predetermined criterion conditions, thereby reducing the acceptance efficiency of the detection device; 3. The analog circuit has inherent instability , with the prolongation of the working time, its internal parameters will drift; 4. There is a "quiet time", and the analog device needs to use the track and hold circuit to detect the pre-selected electric detection signal, capture the useful electric detection signal, and complete the electric detection Analysis of signal characteristics, in this state it is usually not possible to respond to subsequent signals in a timely manner

The lightning signal detector described in this Chinese patent document uses a digital signal processor (DSP for short) as a system platform, uses a computer program language to describe the mathematical model of lightning signal recognition, and realizes the lightning signal recognition model and its signal processing on the DSP. Programmable features, compared to the complex criteria that are difficult to achieve in the past detection methods and devices, it can realize the complex model required by the system platform in the DSP through computer programming language, but its shortcomings are: 1. To realize the complex model, A large number of calculations are required, and sometimes complex algorithms have to be used to obtain more realistic results. However, using complex algorithms will occupy huge DSP resources, reduce system performance, affect signal response and processing speed, and there is a risk of data discarding and Possibility of pause in signal response

2. The user-selectable criterion described in it is only for the selection of the cloud flash criterion or the ground flash criterion, so that only the ground flash data or the cloud flash data or both data are obtained, and the identification criterion It is still fixed, and the criterion cannot be corrected or expanded in real time according to the actual situation, and there are limitations

3. The detector described in this patent has data compression and one-out-of-ten technology, but the data it obtains only contains characteristic data that can determine the type of lightning, and does not have the ability to record and transmit full waveform data

4. Its characteristic data does not have the function of local offline storage

[0005] Chinese patent 97109239.7 "Detection method for the arrival time of lightning electromagnetic wave" discloses a time calibration method for the characteristic frequency band of lightning electromagnetic wave, but its specific implementation method is to use an analog filter to band-pass filter the lightning electromagnetic wave, and there is a certain time drift

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