High-frequency signal envelope line extraction method

Abstract

The invention provides a high-frequency signal envelope line extraction method, which comprises the following steps that: n pieces of voltage data in one high-frequency signal cycle are acquired every m high-frequency signal cycles, and n is greater than or equal to 2; performing Hilbert transform on the n pieces of voltage data in each high-frequency signal cycle to obtain n pieces of transformed voltage data in each high-frequency signal cycle; acquiring a high-frequency signal amplitude of each high-frequency signal cycle based on the n pieces of voltage data and the n pieces of transformed voltage data in each high-frequency signal cycle; and sequentially connecting the high-frequency signal amplitudes of all the high-frequency signal cycles to obtain an envelope line of the whole high-frequency signal. According to the invention, the technical problems of difficult signal processing and large amplitude phase delay of an envelope line extraction method in the prior art can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of signal processing, and in particular to a method for extracting an envelope of a high-frequency signal. Background Art

[0002] The zero-flux positioning speed measurement in the high-speed flying car cabin uses the zero-flux coil characteristics of the low vacuum pipe and obtains the position information of the spacecraft through high-frequency signal positioning. The receiving antenna obtains a high-frequency signal related to the position, one of which has a sine signal envelope and the other has a cosine signal envelope. In order to extract the envelope of the high-frequency signal, it is necessary to design a corresponding algorithm in the digital controller, which not only needs to meet the real-time requirements, but also needs to consider the processing performance of the controller.

[0003] The existing envelope extraction algorithm uses multiplication with the same frequency high-frequency signal and obtains the envelope through a low-pass filter. However, this extraction algorithm requires the controller to sample at a very high frequency and complete data processing in a very short time. It is relatively difficult to process high-frequency signals with higher frequencies, and the low-pass filter will produce a large amplitude phase delay. Summary of the invention

[0004] The present invention provides a method for extracting an envelope of a high-frequency signal, which can solve the technical problems of the envelope extraction method in the prior art, such as the difficulty in signal processing and the large amplitude phase delay.

[0005] The present invention provides a method for extracting a high-frequency signal envelope, the method comprising:

[0006] At every m high-frequency signal cycles, n voltage data within one high-frequency signal cycle are collected, where n≥2;

[0007] Performing Hilbert transformation on n voltage data in each high-frequency signal cycle respectively to obtain n transformed voltage data in each high-frequency signal cycle;

[0008] Acquire the high-frequency signal amplitude of each high-frequency signal cycle based on n voltage data in each high-frequency signal cycle and n transformed voltage data;

[0009] The high-frequency signal amplitudes of all high-frequency signal cycles are sequentially connected to obtain the envelope of the entire high-frequency signal.

[0010] Preferably, the n transformed voltage data within each high-frequency signal cycle are obtained by the following formula:

[0011] y(i)=Hilbert(x(i)),i∈[1 , n]

[0012] Wherein, y(i) represents the i-th transformed voltage data within the current high-frequency signal cycle, x(i) represents the i-th voltage data within the current high-frequency signal cycle, n represents the number of collected voltage data, and Hilbert() represents the Hilbert transform function.

[0013] Preferably, the high-frequency signal amplitude of each high-frequency signal cycle is obtained by the following formula:

[0014]

[0015] Wherein, Amp represents the high-frequency signal amplitude of the current high-frequency signal cycle.

[0016] Preferably, the voltage data is collected using an analog-to-digital chip.

[0017] Preferably, a digital controller is used to perform Hilbert transform on the n voltage data in each high-frequency signal cycle.

[0018] Preferably, the frequency m of the high-frequency signal at the sampling interval is determined according to the computing power of the digital controller.

[0019] Preferably, the calculation time of the high-frequency signal amplitude of each high-frequency signal cycle is less than or equal to the time of (m+1) high-frequency signal cycles.

[0020] By applying the technical solution of the present invention, voltage data of one cycle of the high-frequency signal is collected, amplitude calculation is completed using (m+1) cycles, and the acquired amplitudes are connected in series to obtain the envelope of the high-frequency signal. This not only ensures the demand for high-frequency signal amplitude calculation, but also enables the amplitude calculation algorithm in the digital controller to be completed within (m+1) cycles, thereby ensuring the digital realization of the high-frequency signal envelope. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The included drawings are used to provide a further understanding of the embodiments of the present invention, which constitute a part of the specification, are used to illustrate the embodiments of the present invention, and together with the text description, explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 A flow chart of a high-frequency signal envelope extraction method provided according to an embodiment of the present invention is shown;

[0023] Figure 2a A schematic diagram of a sinusoidal high frequency signal provided according to an embodiment of the present invention is shown;

[0024] Figure 2bA schematic diagram of a cosine high frequency signal provided according to an embodiment of the present invention is shown;

[0025] Figure 3a shows a curve diagram of a high frequency signal provided according to an embodiment of the present invention;

[0026] Figure 3b Shown according to Figure 3a A curve diagram of the envelope of the high frequency signal extracted from ;

[0027] Figure 4 A schematic diagram of low computing frequency signal processing provided according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0028] It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0030] Unless otherwise specifically stated, the relative arrangement of the parts and steps described in these embodiments, numerical expressions and numerical values ​​do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0031] like Figure 1 As shown, the present invention provides a method for extracting a high-frequency signal envelope, the method comprising:

[0032] The n voltage data in one high-frequency signal cycle are collected every m high-frequency signal cycles, that is, only the n voltage data in the first high-frequency signal cycle are collected in every (m+1) high-frequency signal cycle; wherein n≥2; the voltage data are collected by using an analog quantity to digital quantity chip; and the number of high-frequency signal cycles m in the sampling interval is determined according to the computing power of the digital controller;

[0033] Performing Hilbert transformation on n voltage data in each high-frequency signal cycle to obtain n transformed voltage data in each high-frequency signal cycle; wherein the Hilbert transformation is performed on n voltage data in each high-frequency signal cycle by using a digital controller;

[0034] Acquire the high-frequency signal amplitude of each high-frequency signal cycle based on n voltage data in each high-frequency signal cycle and n transformed voltage data;

[0035] The high-frequency signal amplitudes of all high-frequency signal cycles are sequentially connected to obtain the envelope of the entire high-frequency signal.

[0036] The present invention collects voltage data of one cycle of the high-frequency signal, uses (m+1) cycles to complete amplitude calculation, and connects the acquired amplitudes in series to obtain the envelope of the high-frequency signal, which not only ensures the demand for high-frequency signal amplitude calculation, but also enables the amplitude calculation algorithm in the digital controller to be completed within (m+1) cycles, thereby ensuring the digital realization of the high-frequency signal envelope.

[0037] In the present invention, the voltage signal obtained by the cabin-borne zero-flux positioning speed measurement receiving antenna is shown in FIG2 , wherein the amplitude of the high-frequency signal presents a sine wave ( Figure 2a ) or a cosine signal ( Figure 2b ), whose amplitude is related to the position. As the position changes, the amplitude of the high-frequency signal is modulated. Therefore, by extracting the envelope of the high-frequency signal, the position information can be obtained.

[0038] The schematic diagram of envelope extraction is shown in Figure 3. The amplitude of each cycle of the high-frequency signal together constitutes the envelope. The frequency of the high-frequency signal is higher than the frequency of the envelope. The amplitude change within several high-frequency cycles will not be large. Therefore, the signal within one cycle is collected, and the amplitude calculation is completed using the time of multiple cycles, thereby realizing envelope extraction at low calculation frequency.

[0039] Among them, signal processing at low computing frequency is as follows Figure 4As shown, a high-speed analog-to-digital (AD) chip is used to collect n voltage data within one cycle (fundamental wave period) of the high-frequency signal, and the amplitude calculation algorithm is completed in the digital controller using the time of (m+1) high-frequency signal cycles, wherein the amplitude calculation algorithm adopts the amplitude calculation method based on Hilbert. Therefore, the high-frequency signal amplitude of the first cycle is calculated within each (m+1) high-frequency signal cycle, and all the amplitude results calculated in sequence are connected in series to obtain the envelope of the entire high-frequency signal.

[0040] According to an embodiment of the present invention, n transformed voltage data within each high-frequency signal cycle are obtained by the following formula:

[0041] y(i)=Hilbert(x(i)),i∈[1 , n]

[0042] Wherein, y(i) represents the i-th transformed voltage data within the current high-frequency signal cycle, x(i) represents the i-th voltage data within the current high-frequency signal cycle, n represents the number of collected voltage data, and Hilbert() represents the Hilbert transform function.

[0043] Among them, it can be determined that n≥2 according to Shannon's sampling law.

[0044] Among them, x(i) and y(i) can form an analytical signal in complex form: z(i)=x(i)+jy(i).

[0045] According to an embodiment of the present invention, the high-frequency signal amplitude of each high-frequency signal cycle is obtained by the following formula:

[0046]

[0047] Wherein, Amp represents the high-frequency signal amplitude of the current high-frequency signal cycle.

[0048] According to one embodiment of the present invention, the calculation time of the high-frequency signal amplitude of each high-frequency signal cycle is less than or equal to the time of (m+1) high-frequency signal cycles, thereby realizing amplitude extraction at a low calculation frequency, which can not only meet the needs of high-frequency signal amplitude calculation, but also ensure the calculation cycle of the digital controller.

[0049] In order to further understand the present invention, the following is combined with FIG. Figure 4 A high-frequency signal envelope extraction method of the present invention is described in detail.

[0050] In this embodiment, the high-frequency signal frequency is 50kHz, a high-frequency signal cycle time is 20us, the high-speed AD chip sampling period is set to 500kHz, and 10 points are collected in each high-frequency signal cycle, that is, n=10. Figure 4 The Hilbert-based amplitude calculation algorithm operates in the digital controller, and the operation cycle is about 40us.

[0051] Therefore, a method is adopted in which data within one high-frequency signal cycle is collected but the calculation period is lengthened. The data is collected normally for one high-frequency signal cycle, and five high-frequency signal cycles (100us) are used for calculation, i.e., m=4, which is equivalent to calculating only the amplitude of the first high-frequency signal cycle and delaying the output of four high-frequency signal cycles. The schematic diagram is shown in FIG3 .

[0052] In summary, the present invention provides a method for extracting the envelope of a high-frequency signal. For a high-frequency signal with a higher frequency, a high-speed acquisition chip is used to collect data points within one cycle, and a digital controller is used to calculate the amplitude information of the cycle within multiple cycles, thereby realizing amplitude extraction at a low calculation frequency, which can meet the needs of high-frequency signal amplitude calculation and ensure the calculation cycle of the digital controller.

[0053] Parts of the present invention that are not described in detail are well known to those skilled in the art.

[0054] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0055] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0056] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0057] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for extracting a high-frequency signal envelope, characterized in that: The method comprises: At every m high-frequency signal cycles, n voltage data within one high-frequency signal cycle are collected, where n≥2; Performing Hilbert transformation on n voltage data in each high-frequency signal cycle respectively to obtain n transformed voltage data in each high-frequency signal cycle; Acquire the high-frequency signal amplitude of each high-frequency signal cycle based on n voltage data in each high-frequency signal cycle and n transformed voltage data; The high-frequency signal amplitudes of all high-frequency signal cycles are sequentially connected to obtain the envelope of the entire high-frequency signal.

2. The method according to claim 1, characterized in that The n transformed voltage data within each high-frequency signal cycle are obtained by the following formula: y(i)=Hilbert(x(i)),i∈[1 , n] Wherein, y(i) represents the i-th transformed voltage data within the current high-frequency signal cycle, x(i) represents the i-th voltage data within the current high-frequency signal cycle, n represents the number of collected voltage data, and Hilbert() represents the Hilbert transform function.

3. The method according to claim 1, characterized in that The high-frequency signal amplitude of each high-frequency signal cycle is obtained by the following formula: Wherein, Amp represents the high-frequency signal amplitude of the current high-frequency signal cycle.

4. The method according to claim 1, characterized in that: The voltage data is collected using an analog-to-digital chip.

5. The method according to claim 1, characterized in that A digital controller is used to perform Hilbert transformation on n voltage data in each high-frequency signal cycle.

6. The method according to claim 5, characterized in that The frequency m of the high-frequency signal at the sampling interval is determined according to the computing power of the digital controller.

7. The method according to claim 1, characterized in that The calculation time of the high-frequency signal amplitude of each high-frequency signal cycle is less than or equal to the time of (m+1) high-frequency signal cycles.

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