阅读说明：本技术 一种具有谐波抑制功能的射频能量收集天线及其制作方法 (Radio frequency energy collection antenna with harmonic suppression function and manufacturing method thereof ) 是由 孙虎成 姚峰 于 2020-06-12 设计创作，主要内容包括：本发明公开了一种具有谐波抑制功能的射频能量收集天线及其制作方法。制作方法是使用HFSS软件在宽带天线的基础上进行天线仿真设计,通过多次调节宽带天线上与高次谐波相对应枝节长度,使相应高次谐波产生抑制,从而形成所需要的陷波天线。整流天线主要有陷波天线和整流电路组成,介质基板上下两面的金属结构是天线辐射单元,辐射单元是由上下相互平行的交叉枝节组成。本发明是一款能够提高能量收集效率和电压稳定输出的整流天线。(The invention discloses a radio frequency energy collecting antenna with a harmonic suppression function and a manufacturing method thereof. The manufacture method is to use HFSS software to carry out antenna simulation design on the basis of the broadband antenna, and the corresponding higher harmonic is suppressed by adjusting the length of the branch corresponding to the higher harmonic on the broadband antenna for many times, so as to form the required notch antenna. The rectifying antenna mainly comprises a trap antenna and a rectifying circuit, wherein metal structures on the upper surface and the lower surface of a dielectric substrate are antenna radiation units, and the radiation units are composed of cross branches which are parallel to each other from top to bottom. The invention relates to a rectification antenna capable of improving energy collection efficiency and voltage stable output.)

1. A manufacturing method of a radio frequency energy collection antenna with a harmonic suppression function comprises the following specific steps:

step 1, determining a preliminary shape structure and size of an antenna radiation unit;

step 2, optimizing the preliminary shape structure and size of the antenna radiation unit in the step 1 to obtain a broadband antenna;

step 3, the size of the broadband antenna is adjusted for multiple times, so that the broadband antenna generates suppression on the corresponding higher harmonic frequency points, and the shape structure and the size of the antenna with the harmonic suppression function are obtained;

and 4, printing the antenna radiation unit on the dielectric substrate according to the size obtained in the step 3 to obtain a notch antenna, and connecting the notch antenna with a rectifying circuit to obtain a notch rectifying antenna, namely a radio frequency energy collecting antenna with a harmonic suppression function.

2. The method for manufacturing a radio frequency energy harvesting antenna with harmonic suppression function according to claim 1, wherein the antenna radiating unit in step 1 is a log periodic antenna, and the relationship among the parameters of the antenna is as follows:

wherein the content of the first and second substances,L _n is the length of the antenna branch,d _n is the distance between two branches of the antenna,R _n the antenna stub is the vertical distance to the top corner,τa scale factor,Theta isA spacing factor,α isAt an angle.

3. The method for manufacturing a radio frequency energy harvesting antenna with harmonic suppression function according to claim 2, wherein the step of adjusting the broadband antenna in step 3 comprises:

firstly, on the basis of a broadband antenna, suppressing second harmonic, third harmonic and fourth harmonic to obtain a first antenna with a higher frequency band and a function of suppressing without trapped wave;

secondly, on the basis of the first antenna, the length of the antenna branch is adjusted, so that trapped waves are generated between the third harmonic and the fourth harmonic, and a second antenna is obtained;

thirdly, on the basis of the second antenna, the length of the antenna branch is adjusted, so that trapped waves are generated between the second harmonic and the third harmonic, and a third antenna is obtained;

fourthly, on the basis of the third antenna, the length of the antenna branch is adjusted to enable the frequency point | S of the second harmonic and the third harmonic₁₁And if the I is larger than-5 dB, the suppression is further enhanced, and a fourth antenna, namely the trap antenna with the harmonic suppression function, is obtained.

4. The method for manufacturing a radio frequency energy harvesting antenna with harmonic suppression function according to claim 3, wherein the frequency of the second harmonic is 4.9GHz, the frequency of the third harmonic is 7.35GHz, and the frequency of the fourth harmonic is 9.8 GHz.

5. A radio frequency energy collecting antenna with a harmonic suppression function comprises a medium substrate and a rectification circuit, wherein radiation units are arranged on the front side and the back side of the medium substrate, the radio frequency energy collecting antenna is characterized in that the radiation units are of a log periodic structure and comprise middle metal strips and symmetrical branches which are parallel up and down, the branches on the front side and the back side are symmetrically arranged in a crossed mode at intervals, the size of each radiation unit is determined by the method of claim 1, and the radiation units on the medium substrate are connected with the rectification circuit.

6. A radio frequency energy harvesting antenna with harmonic suppression function according to claim 5, wherein the dielectric substrate is Rogers Ro4350, 1.524mm thick, 3.66 dielectric constant, and 0.004 loss tangent.

Technical Field

The invention relates to the technical field of microwave technology and antenna, in particular to a radio frequency energy collecting antenna with a harmonic suppression function and a manufacturing method thereof.

Background

The radio frequency energy collection technology can trace back to the experiment for verifying the existence of electromagnetic waves in 80 Hz in the 19 th century at the earliest; modern technology originated in the 50 th 20 th century, followed by the 1969 in which William Brown designed microwave energy transmission as a power source for helicopters. The radio frequency energy collection technology is developed on the basis of wireless energy transmission, and both the radio frequency energy collection technology and the radio frequency energy collection technology adopt a process of converting radio frequency energy into a direct current power supply by adopting a rectifying antenna. The radio frequency energy collection technology is mainly a process of converting radio frequency energy in the environment into a direct current power supply after collecting the radio frequency energy, and the direct current power supply is supplied to corresponding electronic equipment for use. The technology can solve the technical problem of continuous power supply of intelligent equipment such as low-power wireless sensors, wearable products and the like, and can also provide a miniaturized and convenient power supply device for the following short-board problems of equipment of Internet of things such as intelligent home, biomedical and the like due to small battery size, short service life, high maintenance cost and the like. The nonlinear characteristic of a diode in a rectification circuit in the prior radio frequency energy collection technology can generate higher harmonic waves in the rectification process, so that the rectification efficiency can be reduced. This patent therefore proposes a rectenna with improved energy harvesting efficiency and voltage stabilization output, which simplifies the structure of the whole energy harvesting system while improving efficiency compared to other rectennas.

Disclosure of Invention

The present invention is directed to provide a radio frequency energy harvesting antenna with harmonic suppression function, which overcomes the above-mentioned shortcomings in the prior art.

Another objective of the present invention is to provide a method for manufacturing a radio frequency energy harvesting antenna with harmonic suppression function.

The purpose of the invention is realized by the following technical scheme:

a manufacturing method of a radio frequency energy collection antenna with a harmonic suppression function comprises the following specific steps:

step 1, determining the preliminary shape structure and size of an antenna radiation unit.

And 2, optimizing the preliminary shape structure and size of the antenna radiation unit in the step 1.

And 3, regulating the size of the broadband antenna for multiple times to inhibit the broadband antenna from corresponding higher harmonic frequency points, thereby obtaining the shape structure and size of the antenna with the harmonic suppression function.

And 4, printing the antenna radiation unit on the dielectric substrate according to the size obtained in the step 3 to obtain a notch antenna, and connecting the notch antenna with a rectifying circuit to obtain a notch rectifying antenna, namely a radio frequency energy collecting antenna with a harmonic suppression function.

In a further design scheme of the present invention, the antenna radiating unit in step 1 is a log periodic antenna, and the relationship of each parameter of the antenna is as follows:

wherein L is_nIs the length of the antenna branch, d_nIs the distance between two branches of the antenna, R_nThe antenna stub to vertex angle vertical distance, τ scale factor, θ spacing factor, α angle.

In a further design scheme of the present invention, the step of adjusting the broadband antenna in step 3 is:

firstly, on the basis of a broadband antenna, the second harmonic, the third harmonic and the fourth harmonic are all suppressed, and a first antenna with a high-order frequency band and a function of suppressing without a notch is obtained.

Secondly, on the basis of the first antenna, the length of the antenna branch is adjusted, so that a trapped wave is generated between the third harmonic and the fourth harmonic, and the second antenna is obtained.

And thirdly, on the basis of the second antenna, the length of the antenna branch is adjusted, so that a trapped wave is generated between the second harmonic and the third harmonic, and the third antenna is obtained.

Fourthly, on the basis of the third antenna, the length of the antenna branch is adjusted to enable the frequency point | S of the second harmonic and the third harmonic₁₁And if the I is larger than-5 dB, the suppression is further enhanced, and a fourth antenna, namely the trap antenna with the harmonic suppression function, is obtained.

In a further embodiment of the invention, the frequency of the second harmonic is 4.9GHz, the frequency of the third harmonic is 7.35GHz, and the frequency of the fourth harmonic is 9.8 GHz.

The utility model provides a radio frequency energy collects antenna with harmonic suppression function, includes a medium base plate and rectifier circuit, the positive and negative face of medium base plate all is equipped with radiating element, its characterized in that, radiating element's structure is log periodic structure, including middle metal strip and the symmetry minor matters that is parallel from top to bottom, and the minor matters interval symmetry alternately sets up of positive and negative, radiating element's size is confirmed through above-mentioned method, radiating element on the medium base plate with rectifier circuit connects.

In a further design scheme of the invention, the dielectric substrate is Rogers Ro4350, the thickness is 1.524mm, the dielectric constant is 3.66, and the loss tangent is 0.004.

The invention has the following outstanding advantages:

(1) compared with the traditional receiving antenna, the antenna has the advantages of clear and simple structure and easiness in processing, and can conveniently realize the suppression of corresponding higher harmonic frequency points by adjusting the lengths of the antenna branches. The high-order harmonic waves are restrained, the radio frequency energy collected by the antenna can be effectively limited in the rectifying circuit to be rectified, and the radio frequency energy is not radiated outwards through the antenna. Meanwhile, a voltage stabilizing output circuit is loaded at the rear end of the rectifying circuit to promote the voltage output by rectification to be stably output.

(2) The invention carries out optimization design on the basis of the log periodic antenna, so that the log periodic antenna is more miniaturized, and the volume of the receiving antenna is smaller, so that the energy collecting system is more miniaturized, and the log periodic antenna is matched with the miniaturization requirement of electronic equipment in a modern wireless communication system.

(3) The rectifying antenna improves the efficiency of a radio frequency energy collecting system, and simultaneously removes the loading of a filter circuit in a rear-end rectifying circuit, thereby simplifying the system structure.

Drawings

FIG. 1 is a simplified structural diagram of basic parameters of a log periodic antenna in an embodiment;

FIG. 2 is a front view of an embodiment of a broadband antenna;

FIG. 3 is a side view of an embodiment of a broadband antenna;

FIG. 4 is a diagram of S parameter changes of the first antenna and the broadband antenna in the embodiment;

FIG. 5 is a diagram showing simulated S parameter changes of the first antenna and the second antenna in the embodiment;

FIG. 6 is a diagram showing simulated S parameter changes of the antenna II and the antenna III in the embodiment;

FIG. 7 is a diagram showing simulated S parameter changes of the third antenna and the fourth antenna in the embodiment;

FIG. 8 is a schematic diagram of a rectifier circuit in an embodiment;

FIG. 9 is a schematic diagram of a rectifier circuit in an embodiment;

FIG. 10 is a graph of energy collection efficiency of a notch rectifier circuit versus a broadband rectifier circuit in an embodiment;

FIG. 11 is a flow chart of a radio frequency energy harvesting system;

in the figure, 1-notch antenna, 2-rectifying circuit, 3-upper radiating element, 4-lower radiating element, 5-middle metal strip, 6-branch and 7-dielectric substrate.

Detailed Description

The invention is further explained below with reference to the drawings and examples.