Pulse emission source system for ground penetrating radar

Abstract

The invention relates to a pulse emission source system for ground penetrating radar, which comprises a signal source module, an avalanche transistor module and a shaping module, the signal source module, the avalanche transistor module and the shaping module are connected in sequence, the avalanche transistor module outputs 0-order Gaussian pulse signals, and the shaping module outputs 1-order Gaussian pulse signals. The pulse emission source circuit has the advantages that the avalanche transistor module and the shaping module are arranged, and the pulse emission source circuit capable of generating the pulse with the amplitude larger than + / -150 V and the pulse width of 1.4 ns is designed.

Description

Technical Field

[0001] The invention relates to the field of radar pulse emission sources, in particular to a pulse emission source system for ground penetrating radar. Background Art

[0002] With the development of ground penetrating radar, the pulse amplitude requirements for pulse emission sources are becoming higher and higher. Currently, there is a related project that needs to generate a first-order pulse signal with a pulse amplitude greater than ±150V and a pulse width of about 1.4ns, but at this stage there is no pulse emission source that can meet the above requirements. Summary of the invention

[0003] The purpose of the present invention is to provide a pulse emission source system for ground penetrating radar, which is designed to generate a pulse emission source circuit with a pulse amplitude greater than ±150V and a pulse width of 1.4ns by configuring an avalanche transistor module and a shaping module.

[0004] The objective of the present invention is achieved through the following technical solution: a pulse emission source system for ground penetrating radar, comprising a signal source module, an avalanche triode module and a shaping module, wherein the signal source module, the avalanche triode module and the shaping module are connected in sequence, and the avalanche triode module outputs a 0th order Gaussian pulse signal, and the shaping module outputs a 1st order Gaussian pulse signal.

[0005] Compared with the previous technology, the beneficial effects of the present invention are:

[0006] 1. A pulse emission source circuit that can provide a stable first-order pulse signal with a pulse amplitude greater than ±150V and a pulse width of 1.4ns, meeting the requirements of the project.

[0007] 2. In some embodiments, a pulse repetition frequency can be provided, and the waveform is more stable than that of avalanche transistors in series; in addition, the waveform tail is controllable. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a connection diagram of Embodiment 1 of the present invention;

[0009] Figure 2 This is a connection diagram of Embodiment 2 of the present invention;

[0010] Figure 3 This is a connection diagram of Embodiment 3 of the present invention;

[0011] Figure 4 This is a connection diagram of Embodiment 4 of the present invention;

[0012] Figure 5 is the target waveform diagram of the present invention;

[0013] Figure 6FIG. 4 is a waveform diagram of possible failures in the embodiment of the present invention. DETAILED DESCRIPTION

[0014] The present invention is described in detail below in conjunction with the accompanying drawings:

[0015] like Figure 1-4 As shown: A pulse emission source system for ground penetrating radar, characterized in that it includes a signal source module, an avalanche triode module and a shaping module, the signal source module, the avalanche triode module and the shaping module are connected in sequence, and the avalanche triode module outputs a 0th order Gaussian pulse signal, and the shaping module outputs a 1st order Gaussian pulse signal.

[0016] According to the different types of components and connection relationships, the present invention can be derived into the following embodiments:

[0017] Example 1

[0018] like Figure 1 As shown: the avalanche triode module includes a positive pulse avalanche triode group and a negative pulse avalanche triode group respectively connected to the signal source module, and the positive pulse avalanche triode group and the negative pulse avalanche triode group are both formed by N groups of avalanche triodes connected in series; wherein N is a positive integer greater than 1;

[0019] The shaping module is a balun circuit, which is respectively connected to a positive pulse avalanche triode group and a negative pulse avalanche triode group of the signal source module, and the balun circuit combines the positive pulse signal generated by the positive pulse avalanche triode group and the negative pulse signal generated by the negative pulse avalanche triode group to form a first-order Gaussian pulse signal.

[0020] This embodiment can generate a pulse signal with high voltage and stable pulse width; however, it also has certain limitations: 1. Due to the characteristics of avalanche transistors, the pulse repetition frequency is not high, and it can be conservatively estimated to be 100KHz; 2. When the balun circuit integrates positive and negative pulses, it is affected by time delay, temperature, system stability, etc., and cannot guarantee 100% good synthesis of first-order pulses, that is, the generation of Figure 6 The waveform shown.

[0021] Example 2

[0022] The avalanche triode module comprises a positive pulse avalanche triode group and a negative pulse avalanche triode group respectively connected to the signal source module, wherein the positive pulse avalanche triode group and the negative pulse avalanche triode group are both formed by connecting an avalanche triode and a step-type corresponding diode in series;

[0023] The shaping module is a balun circuit, which is respectively connected to a positive pulse avalanche triode group and a negative pulse avalanche triode group of the signal source module, and the balun circuit combines the positive pulse signal generated by the positive pulse avalanche triode group and the negative pulse signal generated by the negative pulse avalanche triode group to form a first-order Gaussian pulse signal.

[0024] In this embodiment, an avalanche transistor is used to generate the primary avalanche effect, and a step response diode is used for subsequent pulse waveform formation and waveform shaping. It can provide a good pulse repetition frequency, and the waveform is more stable than the series connection of avalanche transistors, and the waveform tail is controllable. According to the existing research and development conditions and technical accumulation, in high-frequency wall-penetrating radars, step response diodes are generally used. The solution of embodiment 2 is currently the best solution. Of course, it also has the following disadvantages: 1. The pulse amplitude cannot be continuously accumulated, and the amplitude is limited; when the balun integrates positive and negative pulses, it may not be able to synthesize the first-order pulse well due to the influence of time delay, temperature, system stability, etc.

[0025] Of course, both embodiments 1 and 2 can ensure a better synthesis effect of the first-order pulse by controlling and adjusting the time delay, temperature, and system stability.

[0026] Example 3

[0027] The avalanche transistor module is formed by N groups of avalanche transistors connected in series; wherein N is a positive integer greater than 1;

[0028] The shaping module is a radio frequency device connected to the avalanche transistor module.

[0029] Embodiment 3 uses avalanche transistors in series cascade to generate a 0th order Gaussian pulse signal, which is then converted into a 1st order Gaussian pulse signal through a radio frequency device. The 1st order pulse signal generated by it is more stable. However, there are also disadvantages: 1. The pulse repetition frequency is not high; 2. The pulse amplitude is reduced by half compared to the balun synthesis solution; 3. New radio frequency devices are introduced, which increases the workload.

[0030] Example 4

[0031] The avalanche transistor module is formed by connecting an avalanche transistor and a step-type corresponding diode in series;

[0032] The shaping module is a radio frequency device connected to the avalanche transistor module.

[0033] Embodiment 4 Avalanche transistors are used to generate the primary avalanche effect, and step response diodes are used for subsequent pulse waveform formation and waveform shaping. Its advantages and disadvantages are the same as those of embodiment 3, and will not be described in detail here.

[0034] It should be noted that in Examples 3 and 4, the radio frequency device is a coupler or a delay line.

[0035] In the above embodiments, the connection methods of the avalanche transistor and the step-type corresponding diode are all conventional technologies, so the present invention will not elaborate on them.

[0036] Finally, the present invention achieves the following objectives: a pulse emission source circuit is designed that can generate a pulse amplitude greater than ±150V and a pulse width of 1.4ns.

[0037] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A pulse emission source system for ground penetrating radar, characterized in that: It includes a signal source module, an avalanche triode module and a shaping module. The signal source module, the avalanche triode module and the shaping module are connected in sequence, and the avalanche triode module outputs a 0th order Gaussian pulse signal, and the shaping module outputs a 1st order Gaussian pulse signal.

2. A pulse emission source system for ground penetrating radar according to claim 1, characterized in that: The avalanche transistor module comprises a positive pulse avalanche transistor group and a negative pulse avalanche transistor group respectively connected to the signal source module, wherein the positive pulse avalanche transistor group and the negative pulse avalanche transistor group are both formed by N groups of avalanche transistors connected in series; wherein N is a positive integer greater than 1; The shaping module is a balun circuit, which is respectively connected to a positive pulse avalanche triode group and a negative pulse avalanche triode group of the signal source module, and the balun circuit combines the positive pulse signal generated by the positive pulse avalanche triode group and the negative pulse signal generated by the negative pulse avalanche triode group to form a first-order Gaussian pulse signal.

3. The pulse emission source system for ground penetrating radar according to claim 1, characterized in that: The avalanche triode module comprises a positive pulse avalanche triode group and a negative pulse avalanche triode group respectively connected to the signal source module, wherein the positive pulse avalanche triode group and the negative pulse avalanche triode group are both formed by connecting an avalanche triode and a step-type corresponding diode in series; The shaping module is a balun circuit, which is respectively connected to a positive pulse avalanche triode group and a negative pulse avalanche triode group of the signal source module, and the balun circuit combines the positive pulse signal generated by the positive pulse avalanche triode group and the negative pulse signal generated by the negative pulse avalanche triode group to form a first-order Gaussian pulse signal.

4. The pulse emission source system for ground penetrating radar according to claim 1, characterized in that: The avalanche transistor module is formed by N groups of avalanche transistors connected in series; wherein N is a positive integer greater than 1; The shaping module is a radio frequency device connected to the avalanche transistor module.

5. The pulse emission source system for ground penetrating radar according to claim 1, characterized in that: The avalanche transistor module is formed by connecting an avalanche transistor and a step-type corresponding diode in series; The shaping module is a radio frequency device connected to the avalanche transistor module.

6. The pulse emission source system for ground penetrating radar according to claim 1, characterized in that: The radio frequency device is a coupler or a delay line.

Images