Broadband pulse generator with center frequency and pulse signal generation method

Abstract

The invention provides a broadband pulse generator with a center frequency and a pulse signal generation method. The broadband pulse generator comprises a step signal source; the signal mixing module comprises at least one transistor, the base electrode of the transistor is connected with the step signal source, and the collector electrode of the transistor is connected with the broadband pulse output end through a blocking capacitor unit; the signal oscillation circuit comprises an oscillation inductor unit and an oscillation capacitor unit which are connected in parallel, one end of the oscillation inductor unit is connected with the emitter of the transistor, and the other end is grounded; wherein the step signal source is used for generating a step signal so as to switch on the transistor, the transistor receives an oscillation signal generated by the signal oscillation circuit and mixes the step signal and the oscillation signal so as to output an ultra-wideband pulse signal with a center frequency to the wideband pulse output end, and the center frequency is the fundamental frequency of the oscillation signal; the fundamental frequency is determined by the inductance value of the oscillation inductance unit and the capacitance value of the oscillation capacitance unit.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of ultra-wideband pulse signals, and in particular to a wideband pulse generator with a center frequency and a pulse signal generating method. Background Art

[0002] In recent years, with the development of wireless communication technology, the application of ultra-wideband (Ul-Wideband, UWB) pulse signals has become more and more extensive. Ultra-wideband pulse signals have significant advantages in high-speed data transmission, radar systems and short-range communications due to their large bandwidth, high capacity, low power consumption and precise positioning. At present, the main methods for generating ultra-wideband pulse signals include but are not limited to the use of high-speed digital-to-analog converters (DACs), relaxation signal oscillation circuits and the use of nonlinear characteristics of radio frequency transistors, as follows:

[0003] High-speed digital-to-analog converter (DAC): A high-speed digital-to-analog converter can generate a wideband pulse signal. This method can achieve precise control of the signal and is suitable for high-order modulation technology. However, this method is limited by the sampling rate and can usually only generate signals within the Nyquist zone. In addition, due to the need for a large amount of logic resources and supporting circuits, the overall system is relatively complex and consumes high power.

[0004] Relaxation signal oscillation circuit: Relaxation signal oscillation circuit is a commonly used method to generate broadband pulse signals, especially suitable for microelectronics processes. This type of signal oscillation circuit can adjust the bandwidth of the output signal by changing the circuit parameters. However, the design and manufacture of the relaxation signal oscillation circuit have extremely high process requirements, which limits its application in conventional board-level circuits.

[0005] RF transistor: Utilize the nonlinear characteristics of RF transistors to generate broadband pulse signals. This method can achieve a wider bandwidth and lower phase noise. However, this solution is usually inefficient and the center frequency of the generated signal cannot be adjusted. Therefore, it is mainly used in some specific industrial radar scenarios.

[0006] In summary, although the existing ultra-wideband pulse generation technologies have their own advantages, they generally have problems such as non-adjustable center frequency, limited bandwidth, and high power consumption. Therefore, developing a broadband pulse generator that can not only ensure high performance but also flexibly adjust the center frequency is crucial to expanding the application scope of ultra-wideband technology. Summary of the invention

[0007] An embodiment of the present invention provides a broadband pulse generator with a center frequency. The broadband pulse generator has a simple structure and can mix a step signal with an oscillation signal generated by a signal oscillation circuit by using a transistor to output an ultra-wideband pulse signal centered on the fundamental frequency of the oscillation signal, thereby ensuring high performance and flexibly adjusting the center frequency.

[0008] To achieve the above-mentioned purpose, an embodiment of the present invention provides a broadband pulse generator with a center frequency, comprising: a step signal source; a signal mixing module, comprising at least one transistor, the base of the transistor is connected to the step signal source, and the collector of the transistor is connected to the broadband pulse output end through a DC blocking capacitor unit; a signal oscillation circuit, comprising an oscillation inductance unit and an oscillation capacitor unit in parallel, one end of the oscillation inductance unit is connected to the emitter of the transistor, and the other end is grounded; wherein the step signal source is used to generate a step signal to turn on the transistor, the transistor receives the oscillation signal generated by the signal oscillation circuit, and mixes the step signal and the oscillation signal to output an ultra-wideband pulse signal with a center frequency to the broadband pulse output end, the center frequency is the fundamental frequency of the oscillation signal, and the fundamental frequency is determined by the inductance value of the oscillation inductance unit and the capacitance value of the oscillation capacitor unit.

[0009] In some embodiments, the broadband pulse generator also includes: a broadband matching module, including at least one matching resistor, one end of the matching resistor is connected to the base of the transistor, and the other end is connected to the grounded end of the oscillation inductance unit; wherein the broadband matching module is used to match the impedance of the step signal source and the base of the transistor.

[0010] In some embodiments, the broadband pulse generator further includes: a power supply module, including a power supply unit and an energy storage inductor, wherein the power supply unit is connected to the collector of the transistor through the energy storage inductor; wherein the power supply module is used to provide the required voltage for the broadband pulse generator.

[0011] In some embodiments, the signal mixing module includes a first transistor and a second transistor, the base of the first transistor is connected to the step signal source, the emitter of the first transistor is connected to the base of the second transistor, the emitter of the first transistor is connected to the signal oscillation circuit, and the collectors of the first transistor and the second transistor are both connected to the broadband pulse output end through the DC blocking capacitor unit.

[0012] In some embodiments, the broadband matching module includes a first matching resistor and a second matching resistor, one end of the first matching resistor is connected to the base of the first transistor, and the other end is connected to the grounded end of the oscillating inductor unit; one end of the second matching resistor is connected to the base of the second transistor, and the other end is connected to the grounded end of the oscillating inductor unit.

[0013] In some embodiments, the first transistor and the second transistor are NPN transistors or PNP transistors.

[0014] In some embodiments, the oscillating capacitor unit includes a varactor diode.

[0015] In some embodiments, the parallel oscillating inductor unit and oscillating capacitor unit are packaged in 0201.

[0016] To achieve the above-mentioned purpose, an embodiment of the present invention provides a method for generating an ultra-wideband pulse signal, which is applied to a broadband pulse generator as described in any one of the above-mentioned embodiments, and the method includes: adjusting the inductance value of the oscillation inductance unit and the capacitance value of the oscillation capacitor unit so that the fundamental frequency of the oscillation signal is a preset first preset frequency, so that the broadband pulse output end of the broadband pulse generator outputs an ultra-wideband pulse signal with a center frequency, and the center frequency is the first preset frequency.

[0017] In some embodiments, one end of the matching resistor is connected to the base of the transistor, and the other end is connected to one end of the oscillation inductance unit that is grounded. After adjusting the inductance value of the oscillation inductance unit and the capacitance value of the oscillation capacitor unit so that the fundamental frequency of the oscillation signal is a preset first preset frequency, the method further includes: using a vector network analyzer to adjust the resistance of the matching resistor under preset excitation power conditions so that the scattering parameter of the broadband pulse generator is lower than a preset threshold value to match the impedance of the step signal source and the base of the transistor; configuring the step signal of the step signal source to excite the base of the transistor so that the broadband pulse output end of the broadband pulse generator outputs an ultra-wideband pulse signal with a center frequency.

[0018] The broadband pulse generator with a center frequency provided by the embodiment of the present invention can use a transistor as a part of a signal mixing module, the base of the transistor receives a signal from a step signal source, the emitter is connected to a signal oscillation circuit, the signal oscillation circuit is composed of an oscillation inductance unit and an oscillation capacitance unit, and is used to generate an oscillation signal, the collector of the transistor is connected to the broadband pulse output end through a DC blocking capacitor, and the output is an ultra-wideband pulse signal with the base frequency as the center; it can be understood that the step signal source can generate a square wave or narrow pulse signal with any duty cycle, and its high and low amplitudes determine the on and off states of the transistor, when the step signal is higher than the on threshold of the transistor, the transistor is turned on, and the signal oscillation circuit starts to work; conversely, when the step signal is lower than the threshold, the transistor is turned off, and the signal oscillation circuit stops working, wherein the signal oscillation circuit is composed of an oscillation inductance and an oscillation capacitance unit. The capacitor composition can change the fundamental frequency, that is, the center frequency, of the signal oscillation loop by adjusting the values ​​of inductance and capacitance. In the half cycle when the transistor is turned on, the step signal and the oscillation signal act on the transistor together. Due to the nonlinear characteristics of the transistor, the two will be mixed. The result of the mixing is a broadband signal that is symmetrically expanded according to the Fourier series with the fundamental frequency of the signal oscillation loop output as the center. In the half cycle when the transistor is turned off, there is no signal output to achieve the output of an ultra-wideband pulse signal with a center frequency. The signal oscillation loop can maintain a stable oscillation frequency to ensure the quality of the output signal. In addition, by adjusting the inductance and capacitance values ​​in the signal oscillation loop, the fundamental frequency of the signal oscillation loop can be changed, thereby adjusting the center frequency of the broadband pulse signal. This adjustment can be achieved by changing the external circuit parameters without the need for complex internal circuit reconstruction, thereby being able to flexibly adjust the center frequency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A circuit diagram of a broadband pulse generator with a center frequency provided by an embodiment of the present invention;

[0020] Figure 2 Another circuit diagram of a broadband pulse generator with a center frequency provided by an embodiment of the present invention;

[0021] Figure 3 Another circuit diagram of a broadband pulse generator with a center frequency provided by an embodiment of the present invention;

[0022] Figure 4 A time domain waveform diagram of a 10 MHz step signal provided by an embodiment of the present invention;

[0023] Figure 5 A spectrum diagram of a 240MHz LC signal oscillation circuit provided by an embodiment of the present invention;

[0024] Figure 6A broadband pulse waveform diagram under 10MHz step signal excitation conditions provided by an embodiment of the present invention;

[0025] Figure 7 A broadband pulse spectrum diagram under 10 MHz step signal excitation conditions provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] In some embodiments, although the functional modules are divided in the system schematic diagram and the logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the system or the order in the flowchart. The terms first, second, etc. in the specification, claims and the above drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0028] In addition, unless otherwise clearly specified and limited, the term "connected" should be understood in a broad sense. For example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or the two can communicate with each other; it can be a direct connection or an indirect connection through an intermediate medium.

[0029] In the description of the embodiments of the present invention, the description with reference to the terms "one embodiment / implementation", "another embodiment / implementation" or "certain embodiments / implementations", "in the above embodiments / implementations", etc. means that the specific features, structures, materials or characteristics described in combination with the embodiments or examples are included in at least two embodiments or implementations disclosed in the present invention. In the disclosure of the present invention, the schematic representation of the above terms does not necessarily refer to the same embodiment or implementation. It should be noted that although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in an order different from that in the flowchart.

[0030] In recent years, with the development of wireless communication technology, the application of ultra-wideband (Ul-Wideband, UWB) pulse signals has become more and more extensive. Ultra-wideband pulse signals have significant advantages in high-speed data transmission, radar systems and short-range communications due to their large bandwidth, high capacity, low power consumption and precise positioning. At present, the main methods for generating ultra-wideband pulse signals include but are not limited to the use of high-speed digital-to-analog converters (DACs), relaxation signal oscillation circuits and the use of nonlinear characteristics of radio frequency transistors, as follows:

[0031] High-speed digital-to-analog converter (DAC): A high-speed digital-to-analog converter can generate a wideband pulse signal. This method can achieve precise control of the signal and is suitable for high-order modulation technology. However, this method is limited by the sampling rate and can usually only generate signals within the Nyquist zone. In addition, due to the need for a large amount of logic resources and supporting circuits, the overall system is relatively complex and consumes high power.

[0032] Relaxation signal oscillation circuit: Relaxation signal oscillation circuit is a commonly used method to generate broadband pulse signals, especially suitable for microelectronics processes. This type of signal oscillation circuit can adjust the bandwidth of the output signal by changing the circuit parameters. However, the design and manufacture of the relaxation signal oscillation circuit have extremely high process requirements, which limits its application in conventional board-level circuits.

[0033] RF transistor: Utilize the nonlinear characteristics of RF transistors to generate broadband pulse signals. This method can achieve a wider bandwidth and lower phase noise. However, this solution is usually inefficient and the center frequency of the generated signal cannot be adjusted. Therefore, it is mainly used in some specific industrial radar scenarios.

[0034] In summary, although the existing ultra-wideband pulse generation technologies have their own advantages, they generally have problems such as non-adjustable center frequency, limited bandwidth, and high power consumption. Therefore, developing a broadband pulse generator that can not only ensure high performance but also flexibly adjust the center frequency is crucial to expanding the application scope of ultra-wideband technology.

[0035] Based on this, the present invention provides a broadband pulse generator with a center frequency. The broadband pulse generator has a simple structure and can mix a step signal and an oscillation signal generated by a signal oscillation circuit using a transistor to output an ultra-wideband pulse signal centered on the fundamental frequency of the oscillation signal, thereby ensuring high performance and flexibly adjusting the center frequency.

[0036] The embodiments of the present invention are further described below in conjunction with the accompanying drawings.

[0037] refer to Figure 1 , Figure 1A circuit diagram of a broadband pulse generator with a center frequency provided by an embodiment of the present invention. The embodiment of the present invention provides a broadband pulse generator with a center frequency, comprising: a step signal source, a direct current power supply Vdd; a signal mixing module, comprising at least one transistor, the base of the transistor is connected to the step signal source, and the collector of the transistor is connected to a broadband pulse output terminal via a direct current isolation capacitor unit (C1); a signal oscillation circuit, comprising an oscillation inductance unit (L2) and an oscillation capacitor unit (C2) connected in parallel, one end of the oscillation inductance unit is connected to the emitter of the transistor, and the other end is grounded; wherein the step signal source is used to generate a step signal to turn on the transistor, the transistor receives the oscillation signal generated by the signal oscillation circuit, and mixes the step signal and the oscillation signal to output an ultra-wideband pulse signal with a center frequency to the broadband pulse output terminal, wherein the center frequency is the fundamental frequency of the oscillation signal, and the fundamental frequency is determined by the inductance value of the oscillation inductance unit and the capacitance value of the oscillation capacitor unit.

[0038] In some embodiments, the broadband pulse generator with a center frequency provided by the embodiment of the present invention can use a transistor as part of a signal mixing module, the base of the transistor receives a signal from a step signal source, and the emitter is connected to a signal oscillation circuit, which is composed of an oscillation inductance unit and an oscillation capacitance unit for generating an oscillation signal, and the collector of the transistor is connected to the broadband pulse output end through a DC blocking capacitor, thereby outputting an ultra-wideband pulse signal centered on the base frequency.

[0039] Among them, it can be understood that the step signal source can generate a square wave or narrow pulse signal with any duty cycle, and its high and low amplitudes determine the on and off states of the transistor. When the step signal is higher than the on threshold of the transistor, the transistor is turned on and the signal oscillation circuit starts to work; conversely, when the step signal is lower than the threshold, the transistor is turned off and the signal oscillation circuit stops working. Among them, the signal oscillation circuit is composed of an oscillation inductor and an oscillation capacitor. By adjusting the values ​​of the inductor and the capacitor, the fundamental frequency of the signal oscillation circuit, that is, the center frequency, can be changed. In the half cycle when the transistor is turned on, the step signal and the oscillation signal act on the transistor together. Due to the nonlinear characteristics of the transistor, the two will be mixed. The result of the mixing is a broadband signal that is centered on the fundamental frequency output by the signal oscillation circuit and is symmetrically expanded according to the Fourier series. In the half cycle when the transistor is turned off, the transistor is neither turned on nor oscillated, and its output is approximately no signal. Therefore, within the full cycle range, the present invention is manifested as a broadband pulse signal generator with a center frequency.

[0040] In some embodiments, the signal oscillation circuit can maintain a stable oscillation frequency to ensure the quality of the output signal. In addition, by adjusting the inductance and capacitance values ​​in the signal oscillation circuit, the base frequency of the signal oscillation circuit can be changed, thereby adjusting the center frequency of the broadband pulse signal. This adjustment can be achieved by changing the external circuit parameters without the need for complex internal circuit reconstruction, thereby being able to flexibly adjust the center frequency. It can be understood that the structure of the present invention generates a fixed output frequency due to the low-noise transistor, the parallel L2 and C2 circuits forming a positive feedback oscillation circuit. The frequency of the base frequency can be adjusted according to the formula Calculation, L and C are inductance and capacitance values ​​respectively, the capacitor can be a common capacitor or a varactor diode, and the oscillation frequency can be flexibly adjusted by changing the capacitance of the capacitor. Among them, the transistor can be a transistor with high-frequency and low-noise output characteristics, such as a RF bipolar or field-effect transistor, and the inductor and capacitor can be corresponding components with high Q value and high self-resonance frequency characteristics.

[0041] refer to Figure 1 In some embodiments, the broadband pulse generator further includes: a broadband matching module, including at least one matching resistor (R), one end of the matching resistor is connected to the base of the transistor, and the other end is connected to the grounded end of the oscillating inductor unit; wherein the broadband matching module is used to match the impedance of the step signal source and the base of the transistor, wherein it can be understood that the main function of the broadband matching module is to match the impedance between the step signal source and the base of the transistor, ensuring that the signal can be efficiently transmitted from the signal source to the transistor, reducing reflection and loss, and by matching the impedance, the reflection and loss of the signal during the transmission process can be reduced, and the energy transmission efficiency can be improved, and the impedance matching helps to improve the signal quality and reduce distortion, so that the transistor can respond to the change of the step signal more accurately.

[0042] refer to Figure 1 In some embodiments, the broadband pulse generator further includes: a power supply module, including a power supply unit and an energy storage inductor (L1), the power supply unit is connected to the collector of the transistor through the energy storage inductor; wherein, the power supply module is used to provide the required voltage for the broadband pulse generator. It can be understood that the power supply module is responsible for providing the required voltage for the broadband pulse generator and stabilizing the supply voltage through the energy storage inductor (L1). The energy storage inductor (L1) can smooth the power supply voltage fluctuations and provide a more stable voltage for the transistor to ensure the reliable operation of the circuit.

[0043] refer to Figures 2 to 3 , Figure 2 Another circuit diagram of a broadband pulse generator with a center frequency provided by an embodiment of the present invention, Figure 3 Another circuit diagram of a broadband pulse generator with a center frequency provided by an embodiment of the present invention, wherein: Figure 2 The medium-broadband pulse generator is a forward-opening Darlington structure broadband pulse generator. Figure 3 A Darlington structure broadband pulse generator with negative opening in the middle; in some embodiments, the signal mixing module includes a first transistor and a second transistor, the base of the first transistor is connected to the step signal source, the emitter of the first transistor is connected to the base of the second transistor, the emitter of the first transistor is connected to the signal oscillation loop, and the collectors of the first transistor and the second transistor are connected to the broadband pulse output terminal through a DC blocking capacitor unit.

[0044] In some embodiments, the broadband matching module includes a first matching resistor and a second matching resistor, one end of the first matching resistor is connected to the base of the first transistor, and the other end is connected to the grounded end of the oscillating inductor unit; one end of the second matching resistor is connected to the base of the second transistor, and the other end is connected to the grounded end of the oscillating inductor unit.

[0045] In some embodiments, the first transistor and the second transistor are NPN transistors or PNP transistors, wherein it can be understood that the corresponding Figure 2 , in the first transistor and the second transistor respectively Figure 2 In the case of Q1 and Q2, the broadband pulse generator is a forward-opened Darlington structure broadband pulse generator. By adopting the Darlington structure, the driving capability of the output current can be significantly increased and the signal strength can be improved; further, through the first matching resistor and the second matching resistor, the impedance between the signal source and the transistor base can be effectively matched, signal reflection can be reduced, and signal transmission efficiency can be improved.

[0046] In some embodiments, corresponding to Figure 3 , in the first transistor and the second transistor respectively Figure 3 In the case of Q1 and Q2, the broadband pulse generator is a negative-open Darlington structure broadband pulse generator, and the signal mixing module, broadband matching module and the negative-open Darlington structure broadband pulse generator are connected. Figure 2 Similar, but the transistor type is PNP transistor. The use of PNP transistor can process negative pulse signals, which can expand the selection range of signal sources, and can also achieve broadband matching through matching resistors to reduce signal reflection.

[0047] In some embodiments, in addition to the above two Darlington structure broadband pulse generators, a mixed structure of NPN and PNP transistors can also be used, or the transistors can be replaced with field effect transistors with similar performance to adapt to different application scenarios and technical requirements.

[0048] In some embodiments, the oscillation capacitor unit includes a varactor diode, and the capacitance value of the oscillation capacitor unit can be flexibly adjusted through the varactor diode, thereby adjusting the center frequency.

[0049] In some embodiments, the parallel-connected oscillating inductor unit and oscillating capacitor unit are packaged in 0201. The oscillating inductor unit and oscillating capacitor unit in 0201 package are helpful to reduce the overall size and parasitic parameters of the circuit and facilitate integration.

[0050] To achieve the above-mentioned purpose, an embodiment of the present invention provides a method for generating an ultra-wideband pulse signal, which is applied to a broadband pulse generator such as any one of the above-mentioned embodiments, and the method includes: adjusting the inductance value of the oscillation inductance unit and the capacitance value of the oscillation capacitor unit so that the fundamental frequency of the oscillation signal is a preset first preset frequency, so that the broadband pulse output end of the broadband pulse generator outputs an ultra-wideband pulse signal with a center frequency, and the center frequency is the first preset frequency.

[0051] In some embodiments, one end of the matching resistor is connected to the base of the transistor, and the other end is connected to the grounded end of the oscillating inductor unit. After adjusting the inductance value of the oscillating inductor unit and the capacitance value of the oscillating capacitor unit so that the fundamental frequency of the oscillation signal is a preset first preset frequency, the method also includes: using a vector network analyzer to adjust the resistance of the matching resistor under preset excitation power conditions so that the scattering parameter of the broadband pulse generator is lower than the preset threshold value to match the impedance of the step signal source and the base of the transistor; configuring the step signal of the step signal source to excite the base of the transistor so that the broadband pulse output end of the broadband pulse generator outputs an ultra-wideband pulse signal with a center frequency.

[0052] refer to Figures 4 to 7 , Figure 4 A time domain waveform diagram of a 10 MHz step signal provided by an embodiment of the present invention; Figure 5 A spectrum diagram of a 240MHz LC signal oscillation circuit provided by an embodiment of the present invention; Figure 6 A broadband pulse waveform diagram under 10MHz step signal excitation conditions provided by an embodiment of the present invention; Figure 7 A broadband pulse spectrum diagram under 10MHz step signal excitation conditions is provided for one embodiment of the present invention; in some embodiments, the goal of adjusting the oscillation inductance unit and the oscillation capacitor unit is to adjust the inductance value (L) of the oscillation inductance unit and the capacitance value (C) of the oscillation capacitor unit so that the fundamental frequency of the oscillation signal reaches a preset first preset frequency (for example, 240MHz), thereby ensuring that the output signal of the broadband pulse generator has a center frequency. Specifically, the oscillation frequency is fine-tuned by adjusting the value of the variable capacitor C2 in the oscillation capacitor unit, and small-sized inductors and capacitors in 0201 packages are used to reduce the influence of parasitic parameters, so that the actual oscillation frequency is as close to the theoretical calculated value as possible.

[0053] In some embodiments, the goal of broadband matching is to ensure that the input impedance of the broadband pulse generator matches the characteristic impedance of the transmission line by adjusting the matching resistor R to reduce signal reflection. Specifically, the resistor R can be connected in parallel with the base of the transistor, and the S11 parameter (reflection coefficient) can be measured using a vector network analyzer at a preset excitation power (e.g., 15 dBm). The value of the resistor R is adjusted until the S11 parameter is lower than a preset threshold (e.g., -10 dB) to ensure that the frequency range covers 20 MHz to 2 GHz. The above process is as follows: Figure 5 As shown in the figure, the spectrum of the LC oscillation circuit at 240MHz is shown in the figure.

[0054] Furthermore, the present invention can excite the base of the transistor by configuring a step signal of a specific frequency (eg, 10 MHz), such as Figure 4 The step signal shown generates an ultra-wideband pulse signal with a center frequency. Specifically, a narrow pulse signal with a high of 2.5V and a low of 0V is configured as the step signal source, and the signal frequency is 10MHz. When this step signal excites the base of the transistor, a broadband pulse signal with a center frequency (240MHz) is observed behind the DC blocking capacitor C1. The result of this process can be observed by Figure 6 (Time Domain Waveform) and Figure 7 (Spectrum diagram) to confirm, it can be seen that the method in the embodiment of the present invention can effectively generate a stable center frequency, and at the same time ensure the effective transmission of the signal through broadband matching. The final ultra-wideband pulse signal meets the design requirements in both time domain and frequency domain.

[0055] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the above-mentioned implementation mode. Technical personnel familiar with the field can also make various equivalent deformations or substitutions without violating the spirit of the present invention. These equivalent deformations or substitutions are all included in the scope defined by the claims of the present invention.

Claims

1. A broadband pulse generator having a center frequency, characterized in that: include: Step signal source; A signal mixing module, comprising at least one transistor, wherein the base of the transistor is connected to the step signal source, and the collector of the transistor is connected to the broadband pulse output terminal via a DC blocking capacitor unit; A signal oscillation circuit, comprising an oscillation inductance unit and an oscillation capacitance unit connected in parallel, wherein one end of the oscillation inductance unit is connected to the emitter of the transistor, and the other end is grounded; Among them, the step signal source is used to generate a step signal to turn on the transistor, the transistor receives the oscillation signal generated by the signal oscillation circuit, and mixes the step signal and the oscillation signal to output an ultra-wideband pulse signal with a center frequency to the wideband pulse output end, the center frequency is the fundamental frequency of the oscillation signal, and the fundamental frequency is determined by the inductance value of the oscillation inductance unit and the capacitance value of the oscillation capacitance unit.

2. The broadband pulse generator with a center frequency according to claim 1, characterized in that: The broadband pulse generator also includes: A broadband matching module, comprising at least one matching resistor, one end of which is connected to the base of the transistor, and the other end of which is connected to a grounded end of the oscillating inductor unit; The broadband matching module is used to match the impedance of the step signal source and the base of the transistor.

3. The broadband pulse generator with a center frequency according to claim 1, characterized in that: The broadband pulse generator also includes: A power module, comprising a power unit and an energy storage inductor, wherein the power unit is connected to the collector of the transistor via the energy storage inductor; Wherein, the power supply module is used to provide the required voltage for the broadband pulse generator.

4. The broadband pulse generator with a center frequency according to claim 2, characterized in that: The signal mixing module includes a first transistor and a second transistor, the base of the first transistor is connected to the step signal source, the emitter of the first transistor is connected to the base of the second transistor, the emitter of the first transistor is connected to the signal oscillation circuit, and the collectors of the first transistor and the second transistor are both connected to the broadband pulse output end through the DC blocking capacitor unit.

5. The broadband pulse generator with a center frequency according to claim 4, characterized in that: The broadband matching module includes a first matching resistor and a second matching resistor, one end of the first matching resistor is connected to the base of the first transistor, and the other end is connected to the grounded end of the oscillating inductor unit; one end of the second matching resistor is connected to the base of the second transistor, and the other end is connected to the grounded end of the oscillating inductor unit.

6. The broadband pulse generator with a center frequency according to claim 4, characterized in that: The first transistor and the second transistor are NPN transistors or PNP transistors.

7. The broadband pulse generator with a center frequency according to claim 1, characterized in that: The oscillating capacitor unit includes a varactor diode.

8. The broadband pulse generator with a center frequency according to claim 1, characterized in that: The parallel oscillating inductance unit and oscillating capacitance unit are packaged in 0201.

9. A method for generating an ultra-wideband pulse signal, characterized in that: The method is applied to the broadband pulse generator according to any one of claims 1 to 7, and the method comprises: The inductance value of the oscillation inductance unit and the capacitance value of the oscillation capacitor unit are adjusted so that the fundamental frequency of the oscillation signal is a preset first preset frequency, so that the broadband pulse output end of the broadband pulse generator outputs an ultra-wideband pulse signal with a center frequency, and the center frequency is the first preset frequency.

10. The method for generating an ultra-wideband pulse signal according to claim 9, characterized in that: One end of the matching resistor is connected to the base of the transistor, and the other end is connected to a grounded end of the oscillating inductor unit. After adjusting the inductance value of the oscillating inductor unit and the capacitance value of the oscillating capacitor unit so that the fundamental frequency of the oscillation signal is a preset first preset frequency, the method further includes: Using a vector network analyzer to adjust the resistance of the matching resistor under a preset excitation power condition so that the scattering parameter of the broadband pulse generator is lower than a preset threshold value to match the impedance of the step signal source and the base of the transistor; The step signal of the step signal source is configured to excite the base of the transistor, so that the broadband pulse output end of the broadband pulse generator outputs an ultra-wideband pulse signal with a center frequency.

Images