Omnidirectional broadband high-gain rectification antenna

Abstract

The invention discloses an omnidirectional broadband high-gain rectification antenna which comprises an antenna unit radiation structure, an antenna unit radiation patch, an upper dielectric plate, a first rectification circuit, a second rectification circuit, a metal plate, a lower dielectric plate and an antenna unit feed structure. Wherein the first rectifying circuit and the second rectifying circuit are both printed on the upper surface of the upper-layer dielectric plate; the first rectifying circuit is connected with the first port of the antenna unit and is used for receiving radio frequency energy in the environment; and the second rectifying circuit is connected with the second port and the third port of the antenna unit and is used for receiving radio frequency energy from the fixed radio frequency source. The antenna can be applied to radio frequency energy collection and wireless energy transmission at the same time, and has the characteristics of omnidirectional broadband and high gain. The antenna can be widely applied to the field of microwave rectification antennas.

Description

Technical Field

[0001] The invention relates to the field of microwave rectennas, and in particular to an omnidirectional, broadband, high-gain rectenna. Background Art

[0002] Microwave wireless energy transmission technology provides a new way to solve the energy supply problem. By getting rid of the constraints of physical cables, it realizes contactless transmission of energy in space. This technology does not require the use of wires to transmit electrical energy. An energy receiver is directly installed at the working electronic device, and then the electromagnetic energy is transmitted to the receiver wirelessly through the transmitter. It can work conveniently in complex and changeable environments, and it does not pollute the environment. It provides an ideal solution for charging various electronic devices that are difficult to power manually.

[0003] In modern RF environments, due to the large number of RF signal sources and their wide distribution, such as wireless communication base stations, Wi-Fi routers, radio and television transmission towers, etc., the directions and frequencies of the signals transmitted by these signal sources are different. Omnidirectional rectennas can receive RF signals at various angles in the horizontal and vertical directions, avoiding the situation where directional antennas miss some signals due to pointing problems. For example, in an urban environment, the surrounding RF signals are chaotic, and omnidirectional antennas can ensure that signals coming from all directions have a chance to be collected, whether the signal comes from Wi-Fi devices in nearby buildings or from distant communication base stations. In addition, since the frequency of the signal source is widely distributed, in order to make the rectenna have more energy, the rectenna should cover the working frequency bands of some more popular signal sources as much as possible, such as: GSM-1800, UMTS-2100, ISM-2400, 5G-3500, ISM-5800 and WLAN communication bands.

[0004] Existing rectennas are deficient in bandwidth. Traditional rectenna designs are mostly based on specific narrowband frequencies, which is determined by the design of the antenna structure, matching circuit, and rectifier circuit. Narrowband rectennas can only utilize RF energy within a very narrow frequency band, resulting in a large amount of energy in other frequency bands being wasted. For example, in an urban environment, the RF signal spectrum is complex, and a narrowband rectenna may only be able to capture signals from a certain frequency band of a specific operator, and cannot fully utilize the energy in other frequency bands, greatly reducing the energy collection efficiency.

[0005] In wireless energy transmission scenarios, gain is an important performance indicator. In wireless energy transmission, the transmitted electromagnetic waves will decay rapidly as the distance increases. High-gain rectennas can effectively compensate for this energy attenuation. In the case of long-distance transmission, high-gain antennas can increase the effective receiving area and better receive the energy emitted by the transmitter.

[0006] Since RF energy harvesting and wireless energy transmission have different requirements for antenna performance indicators, in RF energy harvesting, due to the uncertainty of RF source position and frequency, broadband omnidirectional rectifying antennas are often our design goals. Existing rectifying antennas cannot be used for both RF energy harvesting and wireless energy transmission at the same time, and it is difficult to further optimize them. Summary of the invention

[0007] In view of this, the present invention proposes an omnidirectional wideband, high-gain rectifying antenna that can be used for both radio frequency energy collection and wireless energy transmission, including an antenna unit radiation structure, an antenna unit radiation patch, an upper dielectric plate, a first rectifying circuit, a second rectifying circuit, a metal plate, a lower dielectric plate, and an antenna unit feeding structure, wherein:

[0008] The receiving antenna is connected to the first rectifier circuit and the second rectifier circuit through an SMA connector;

[0009] The first rectifier circuit is a broadband high-efficiency rectifier circuit, and the first rectifier circuit is connected to the first port of the antenna unit and is used to receive radio frequency energy in the environment;

[0010] The second rectifier circuit is a power distribution insensitive rectifier circuit, and the second rectifier circuit is connected to the second port and the third port of the antenna unit, and is used to receive radio frequency energy from a fixed radio frequency source;

[0011] The first rectifier circuit and the second rectifier circuit are both printed or welded on the upper surface of the upper dielectric plate;

[0012] The metal plate is printed on the lower surface of the upper dielectric plate;

[0013] The receiving antenna is used to receive radio frequency energy and transmit the energy to the rectifier circuit. The rectifier circuit converts the radio frequency energy into direct current energy and outputs a direct current voltage on the rectifier circuit load.

[0014] The antenna unit radiation structure is formed by cross-jointing two single-sided printed circuit boards of the same size, and its patch structure is composed of irregular patches.

[0015] The antenna unit radiation patch is composed of a cross of rectangular metal patches with a square slot etched in the middle;

[0016] The antenna unit feeding structure consists of two traditional T-type power dividers.

[0017] In some embodiments, the broadband high-efficiency rectification circuit includes a first capacitor, a coupled-line broadband matching network, a voltage doubler rectification structure, a first harmonic suppression network, a first filter circuit, and a first resistor connected in sequence.

[0018] Among them, the coupled line broadband matching network is composed of five microstrip lines, the voltage doubler rectification structure includes a diode and a microstrip line, the first harmonic suppression network includes multiple microstrip lines, and the first filter circuit includes a capacitor and a microstrip line.

[0019] In some embodiments, the power distribution insensitive rectification circuit includes an orthogonal coupler, a capacitor, a parallel rectification structure, a second harmonic suppression network, and a second filtering circuit connected in sequence.

[0020] The orthogonal coupler is composed of eight microstrip lines, the parallel rectification structure includes a diode and a plurality of microstrip lines, the second harmonic suppression network is composed of six microstrip lines, and the second filtering circuit includes a capacitor and a plurality of microstrip lines.

[0021] Based on the above scheme, the present invention provides an omnidirectional, broadband, high-gain rectifying antenna, whose first port can realize broadband capture of radio frequency energy in the environment, and whose second port and third port can efficiently receive radio frequency energy emitted from a specific position; the rectifying antenna of the present invention receives radio frequency energy in the environment, and then transmits it to the rectifying circuit for rectification. Since the broadband omnidirectional antenna subunit and the rectifying circuit in the receiving antenna both have broadband characteristics, higher energy conversion efficiency can be achieved within a wider frequency range; the omnidirectional, broadband, high-gain rectifying antenna proposed by the present invention, which can be simultaneously applied to radio frequency energy collection and wireless energy transmission, has a wider bandwidth and higher gain than existing rectifying antennas. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural schematic diagram of an omnidirectional wide-band high-gain rectifying antenna of the present invention;

[0023] Figure 2 It is a schematic diagram of the splitting of the dual-polarization high-gain antenna subunit of the present invention;

[0024] Figure 3 It is a schematic diagram of the disassembly of the broadband omnidirectional antenna subunit of the present invention;

[0025] Figure 4 is a circuit diagram of a first rectifier circuit of the present invention;

[0026] Figure 5 is a circuit diagram of a second rectifier circuit of the present invention;

[0027] Figure 6 These are the simulation and test results of the S parameters of the receiving antenna of the embodiment of the present invention at 1.4-3.8 GHz.

[0028] Figure 7 These are the simulation and test results of the S parameters of the receiving antenna of the embodiment of the present invention at 5.6-6.0 GHz.

[0029] Figure 8This is the directional diagram of the receiving antenna port 1 of the embodiment of the present invention tested in a microwave darkroom when the operating frequency is 2.47 GHz.

[0030] Fig. 9 It is a simulation and test result diagram of the antenna gain of the receiving antenna port 1 of the embodiment of the present invention when the operating frequency is 1.4-3.8 GHz.

[0031] Fig.10 It is a simulation and test result diagram of the antenna gain of the receiving antenna port 2 of the embodiment of the present invention when the operating frequency is 5.6-6.0 GHz.

[0032] Fig.11 It is a simulation and test result diagram of the antenna gain of the receiving antenna port 3 of the embodiment of the present invention when the operating frequency is 5.6-6.0 GHz.

[0033] Fig.12 This is a test diagram of the rectifying efficiency of the rectifying antenna in the range of 1.4-3.8 GHz according to an embodiment of the present invention.

[0034] Fig.13 This is a test diagram of the rectifying efficiency of the rectenna of an embodiment of the present invention at 5.6-6.0 GHz.

[0035] Figure numerals: I, coupled line broadband matching network; II, voltage doubler rectification structure; III, first harmonic suppression network; IV, first filter circuit; C1, first capacitor; R1, first resistor; 1, first microstrip line; 2, second microstrip line; 3, third microstrip line; 4, fourth microstrip line; 5, fifth microstrip line; 6, sixth microstrip line; 7, seventh microstrip line; 8, eighth microstrip line; 9, ninth microstrip line; 10, tenth microstrip line; 11, eleventh microstrip line; 12, twelfth microstrip line; V, orthogonal coupler; VI, parallel rectification structure; VII, second harmonic suppression network; VIII, second filter circuit; 13, thirteenth microstrip line; 14, fourteenth microstrip line; 15, fifteenth microstrip line; 16, sixteenth microstrip line; 17, seventeenth microstrip line; 18, the eighteenth microstrip line; 19, the nineteenth microstrip line; 20, the twentieth microstrip line; 21, the twenty-first microstrip line; 22, the twenty-second microstrip line; 23, the twenty-third microstrip line; 24, the twenty-fourth microstrip line; 25, the twenty-fifth microstrip line; 26, the twenty-sixth microstrip line; 27, the twenty-seventh microstrip line; 28, the twenty-eighth microstrip line; 29, the twenty-ninth microstrip line; 30, the thirtieth microstrip line; 31, the thirty-first microstrip line; 32, the thirty-second microstrip line; 33, the thirty-third microstrip line; 34, the thirty-fourth microstrip line; 35, the thirty-fifth microstrip line; C3, the third capacitor; C4, the fourth capacitor; D3, the third diode; D4, the fourth diode; C5, the fifth capacitor; C6, the sixth capacitor; R2, the second resistor. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0037] It should be noted that, for the convenience of description, only the parts related to the relevant invention are shown in the drawings. In the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other.

[0038] It should be understood that the "device", "unit" and / or "module" used in this application is a method for distinguishing different components, elements, parts, parts or assemblies at different levels. However, if other words can achieve the same purpose, the word can be replaced by other expressions.

[0039] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "a kind" and / or "the" do not refer to the singular, but also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of clearly identified steps and elements, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements. The elements defined by the sentence "includes a..." do not exclude the existence of other identical elements in the process, method, commodity or device that includes the elements.

[0040] In the description of the embodiments of the present application, "plurality" means two or more than two. The following terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0041] Reference Figure 1 , is a schematic diagram of a split example of an optional example of the omnidirectional wideband high-gain rectenna proposed in the present invention. The rectenna proposed in this embodiment may include but is not limited to the following structures:

[0042] The receiving antenna is divided into two parts: a dual-polarization high-gain antenna subunit and a broadband omnidirectional antenna subunit. The two antenna units are embedded together through the design of protrusions and grooves on the dielectric plate.

[0043] The dual-linear polarization high-gain antenna subunit serves as a receiving antenna for wireless energy transmission, and includes, from top to bottom, a dual-linear polarization high-gain antenna unit radiation patch, an upper dielectric plate, a metal plate, a lower dielectric plate, and a dual-linear polarization high-gain antenna unit feeding structure.

[0044] The upper dielectric plate and the lower dielectric plate are annular dielectric substrates with an outer radius of R1 = 110 mm and an inner radius of R2 = 0.5 mm. The thickness of the upper dielectric plate is H1 = 1.5 mm, and the thickness of the lower dielectric plate is H2 = 0.5 mm. The material of the dielectric plate is F4B220, the dielectric constant εr is 2.2, and the loss tangent tanδ is 0.001.

[0045] like Figure 2 As shown, the dual-polarization high-gain antenna unit radiation patch is composed of two rectangular metal patches with a length of L1 = 54.2 mm and a width of L2 = 18.4 mm. A square slot with a length of S1 = 17.4 mm is etched in the middle of the radiation patch to increase the gain of the antenna and help combine the broadband omnidirectional antenna subunit.

[0046] The metal plate is the metal floor of the dual-polarization high-gain antenna subunit and the broadband omnidirectional antenna subunit. It is in the shape of a ring with an outer radius of R1=110mm and an inner radius of R3=1.5mm. There are four centrally symmetrical rectangular grooves with a length of L3=10mm and a width of W1=1mm etched around it for coupling feeding.

[0047] The dual-polarization high-gain antenna unit feeding structure is composed of two T-type power dividers, wherein the width of the microstrip line with a characteristic impedance of 71Ω is W2=0.85mm, and the width of the microstrip line with a characteristic impedance of 50Ω is W3=1.5mm.

[0048] like Figure 3As shown, the broadband omnidirectional antenna subunit is used as a receiving antenna for collecting radio frequency energy, and is formed by cross-jointing two single-sided printed circuit boards of the same size. The antenna is printed on a square dielectric substrate with a thickness of H = 0.5mm, a length of L1 = 80mm, and a width of W1 = 27.5mm. The material of the dielectric substrate is F4B220, with a dielectric constant εr of 2.2 and a loss tangent tanδ of 0.015. A groove is cut in the middle of the dielectric plate so that the two dielectric plates can be cross-jointed. Square protrusions with a length of L2 = 6mm are designed on both sides of the dielectric plate to connect the floor and fix the radiation structure of the antenna unit. The patch structure is composed of irregular patches, including an inverted triangle with a long side length of L3 = 52mm and a height of W2 = 27mm; at both ends of the inverted triangle, there are short-circuited microstrip lines with a length of L4 = 27mm and a width of W3 = 0.2mm; a strip groove with a width of W4 = 2mm is etched in the middle; and a strip groove with a width of W5 = 0.95mm is etched on the left and right sides of the metal patch to achieve a better matching effect. Further, short-circuited microstrip lines with a length of L5 = 15mm and a width of W6 = 1.5mm are etched on both sides of the patch, connected to the metal floor of the lower layer of the receiving antenna, expanding the matching bandwidth of the broadband omnidirectional antenna subunit. Further, a rectangular groove with a length of L6 = 21mm and a width of W7 = 13mm is etched directly above the middle of the metal patch to reduce the blocking of the broadband omnidirectional antenna subunit metal patch on the electromagnetic radiation of the lower layer dual-polarization high-gain antenna unit.

[0049] In some possible embodiments, such as Figure 4 As shown, in order to combine the broadband omnidirectional antenna unit of the receiving antenna to realize broadband RF energy collection, a broadband voltage doubler circuit based on coupled lines to realize broadband matching is proposed, and its microstrip structure and components are printed and welded on the upper surface of the upper dielectric board. In this example, the input port of the rectifier circuit is connected to port 1 of the receiving antenna. The first rectifier circuit of the present invention is a broadband voltage doubler circuit based on coupled lines to realize broadband matching, including a coupled line broadband matching network I, a voltage doubler rectifier structure II, a first harmonic suppression network III, a first filter circuit IV, a first capacitor C1 and a first resistor R1.

[0050] The coupled line broadband matching network I is composed of microstrip lines (1, 2, 3, 4, 5), wherein the second microstrip line 2, the third microstrip line 3 and the fourth microstrip line 4 form a coupled line structure for broadband matching of the rectifier circuit. The first end of the first microstrip line 1 is connected to the first capacitor C1, and the first microstrip line 1 is parallel to the third microstrip line 3 and the fifth microstrip line 5; the second microstrip line 2 is perpendicular to the first microstrip line 1 and the third microstrip line 3, and the second microstrip line 2 is located between the first microstrip line 1 and the third microstrip line 3; the fourth microstrip line is perpendicular to the third microstrip line 3 and the fifth microstrip line 5, and the fourth microstrip line 4 is located between the third microstrip line 3 and the fifth microstrip line 5. The port is connected to the port 1 of the receiving antenna through an SMA connector, and is used to input the radio frequency energy received by the receiving antenna in the environment. The coupled line broadband matching network is used to achieve broadband impedance matching between the input source and the voltage doubler rectifier structure II.

[0051] The voltage doubler rectifier structure II includes a first diode D1, a second diode D2 and a sixth microstrip line 6. The anode of the first diode D1 is connected to the sixth microstrip line 6; the cathode of the first diode D1, the anode of the second diode D2 and the right end of the fifth microstrip line 5 are connected; the cathode of the second diode D2 is connected to the first harmonic suppression network III, and the end of the sixth microstrip line 6 is connected to the bottom metal plate through a metal via.

[0052] The first harmonic suppression network III is composed of microstrip lines (7, 8, 9, 10), the left end of the seventh microstrip line 7 is connected to the cathode of the second diode D2, and the right end of the seventh microstrip line 7 is connected to the eighth microstrip line 8; the ninth microstrip line 9 and the tenth microstrip line 10 are respectively vertically connected to the upper and lower sides of the eighth microstrip line 8, and the ninth microstrip line 9 and the tenth microstrip line 10 have the same structure, both of which are fan-shaped, and jointly achieve broadband harmonic suppression.

[0053] The first filtering circuit IV includes a second capacitor C2 and microstrip lines (11, 12). The left end of the eleventh microstrip line 11 is connected to the eighth microstrip line 8. The second capacitor C2 is connected between the eleventh microstrip line 11 and the twelfth microstrip line 12. The eleventh microstrip line 11 is perpendicular to the twelfth microstrip line 12. The end of the twelfth microstrip line 12 is connected to the bottom metal plate through a metal via.

[0054] In order to realize a broadband and high-efficiency rectifier circuit, the voltage doubler rectifier topology has a smaller impedance fluctuation with frequency than the single-tube series rectifier topology and the single-tube parallel circuit rectifier topology, and is more suitable for realizing a broadband rectifier circuit. In this example, two parallel fan-shaped branches are used to form a harmonic suppression network III to achieve broadband harmonic suppression, and the harmonics are reflected back into the voltage doubler rectifier structure II to improve the rectification efficiency of the circuit. The function of the first filter circuit IV is to filter out the harmonics that are not suppressed by the first harmonic suppression network III.

[0055] The diode model selected in this example is HSMS-2852 from Avago, and the dielectric substrate used is Arlon-AD255C, which has a thickness of 0.762mm, a relative dielectric constant of 2.55, and a loss tangent of 0.0018. The specific circuit dimensions are as follows: the length of the first microstrip line 1 = 5.4mm, width = 1mm; the length of the second microstrip line 2 = 3.3mm, width = 3mm; the length of the third microstrip line 3 = 4mm, width = 1mm; the length of the fourth microstrip line 4 = 3.3mm, width = 0.2mm; the length of the fifth microstrip line 5 = 6.3mm, width = 0.2mm; the length of the sixth microstrip line 9 = 3mm, width = 2.1mm; the length of the seventh microstrip line 7 = 6.3mm, width = 3.5mm m; the eighth microstrip line 8 has a length of 2 mm and a width of 2.1 mm; the ninth microstrip line 9 has a length of 14.41 mm and an angle of 30°; the tenth microstrip line 10 has a length of 14.41 mm and an angle of 30°; the eleventh microstrip line 11 has a length of 6.4 mm and a width of 2.1 mm; the twelfth microstrip line 12 has a length of 1.5 mm and a width of 2.1 mm; the first capacitor 13 has a length of 47 pF; the second capacitor 14 has a length of 47 pF; the first resistor R1 has a length of 1100 Ω. The overall size of the circuit is 50 mm × 45 mm.

[0056] In some feasible embodiments, in order to combine the dual-polarization high-gain antenna unit of the receiving antenna to achieve high-gain, polarization-insensitive wireless energy transmission, a rectifier circuit insensitive to input power distribution is proposed, that is, a second rectifier circuit, which is printed and welded on the upper surface of the upper dielectric board, such as Figure 5 As shown, it includes an orthogonal coupler V, a parallel rectification structure VI, a second harmonic suppression network VII, a second filtering circuit VIII, a third capacitor C3 and a fourth capacitor C4.

[0057] In this example, the input port of the rectifier circuit is connected to port 2 and port 3 of the receiving antenna through an SMA connector. When the dual-polarization high-gain antenna unit of this example is used for wireless energy transmission, the different polarization angles between the transmitting ends will cause different energy proportions allocated to port 2 and port 3.

[0058] The orthogonal coupler is composed of microstrip lines (13, 14, 15, 16, 17, 18, 19, 20). The function of the orthogonal coupler V is to evenly distribute the radio frequency energy received by the receiving antenna port 2 and the port 3 to the two subsequent sub-rectifiers. The thirteenth microstrip line 13, the fourteenth microstrip line 14, and the fifteenth microstrip line 15 are connected in sequence, and the sixteenth microstrip line 16, the seventeenth microstrip line 17, and the eighteenth microstrip line 18 are connected in sequence; the nineteenth microstrip line 19 is perpendicular to and connected to the fourteenth microstrip line 14 and the fifteenth microstrip line 15, and is located on the left side of the fourteenth microstrip line 14 and the fifteenth microstrip line 15; the twentieth microstrip line 20 is perpendicular to and connected to the fourteenth microstrip line 14 and the fifteenth microstrip line 15, and is located on the right side of the fourteenth microstrip line 14 and the fifteenth microstrip line 15.

[0059] The parallel rectification structure is composed of a third diode D3, a fourth diode D4, and microstrip lines (21, 22, 23, 24, 25, 26). The left side of the twenty-first microstrip line 21 is connected to the third capacitor C3, and the right side is connected to the twenty-second microstrip line 22; the cathode of the third diode D3 is connected to the upper side of the twenty-second microstrip line 22, and the anode is connected to the lower end of the twenty-third microstrip line 23; the twenty-third microstrip line 23 is perpendicular to the twenty-second microstrip line 22, and the upper end of the twenty-third microstrip line 23 is connected to the underlying metal plate through a metal via; the structure of the lower half is similar to that of the upper half, so it is not described in detail.

[0060] The second harmonic suppression network VII is composed of microstrip lines (27, 28, 29, 30, 31, 32), and its function is to reflect the first harmonic back into the parallel rectifier structure VI to improve the rectification efficiency of the circuit. The left end of the twenty-seventh microstrip line 27 is connected to the right end of the twenty-second microstrip line 22, the right end of the twenty-seventh microstrip line 27 is connected to the left end of the twenty-eighth microstrip line 28, and the twenty-ninth microstrip line 29 is vertically connected to the left side of the twenty-eighth microstrip line 28; the structure of the lower half is similar to that of the upper half, so it will not be described in detail.

[0061] The second filtering circuit VIII is composed of microstrip lines (33, 34, 35), a fifth capacitor C5, a sixth capacitor C6, and a second resistor R2, and its function is to filter out harmonics that are not suppressed by the second harmonic suppression network VII. The thirty-fourth microstrip line 34 is perpendicular to the twenty-eighth microstrip line 28, and its end is connected to the metal plate through a metal via, and the lower end of the thirty-fourth microstrip line 34 is connected to the twenty-eighth microstrip line 28 through the fifth capacitor C5; the thirty-third microstrip line 33 is perpendicular to and connected to the twenty-eighth microstrip line 28 and the thirty-first microstrip line 31, and the thirty-third microstrip line 33 is also connected to the second resistor R2; the thirty-sixth microstrip line 36 is perpendicular to the thirty-first microstrip line 31, and the thirty-sixth microstrip line 36 is connected to the thirty-first microstrip line 31 through the sixth capacitor C6, and the end of the thirty-sixth microstrip line 36 is connected to the metal plate through a metal via.

[0062] The diode model selected in this example is Infineon's BAT15-03w, and the dielectric substrate used is Arlon-AD255C, which has a thickness of 0.762mm, a relative dielectric constant of 2.55, and a loss tangent of 0.0018. The specific circuit dimensions are as follows: the length of the thirteenth microstrip line 13 = 4mm, the width = 2.15mm; the length of the sixteenth microstrip line 16 = 4mm, the width = 2.1mm; the length of the nineteenth microstrip line 19 = 6.7mm, the width = 2.15mm; the length of the fourteenth microstrip line 14 = 10.1mm, the width = 3.52mm; the length of the seventeenth microstrip line 17 = 10.1mm, the width = 3.52mm; the length of the twentieth microstrip line 20 = 6.7mm, the width = 2 .15mm; the length of the fifteenth microstrip line 15 is 3mm, the width is 2.15mm; the length of the eighteenth microstrip line 18 is 3mm, the width is 2.15mm; the length of the twenty-first microstrip line 21 is 4.1mm, the width is 1mm; the length of the twenty-second microstrip line 22 is 2.1mm, the width is 2.1mm; the length of the twenty-third microstrip line 23 is 3mm, the width is 2.1mm; the length of the twenty-fourth microstrip line 24 is 4.1mm, the width is 1mm; the length of the twenty-fifth microstrip line 2 Line 25 has a length of 2.1 mm and a width of 2.1 mm; the twenty-sixth microstrip line 26 has a length of 3 mm and a width of 2.1 mm; the twenty-seventh microstrip line 27 has a length of 2.9 mm and a width of 1 mm; the twenty-eighth microstrip line 28 has a length of 4 mm and a width of 1 mm; the twenty-ninth microstrip line 29 has a length of 9.4 mm and a width of 1 mm; the thirtieth microstrip line 30 has a length of 2.9 mm and a width of 1 mm; the thirty-first microstrip line 31 has a length of 4 mm and a width of 1 mm m; length of the thirty-second microstrip line 32 = 9.4 mm, width = 1 mm; length of the thirty-fourth microstrip line 34 = 9.3 mm, width = 1 mm; length of the thirty-third microstrip line 33 = 3 mm, width = 2.1 mm; length of the thirty-sixth microstrip line 36 = 3 mm, width = 2.1 mm; third capacitor C3 = 47 pF; fourth capacitor C4 = 47 pF; fifth capacitor C5 = 47 pF; sixth capacitor C6 = 47 pF; load resistor R2 = 330 Ω. The overall size of the circuit is 50 mm × 40 mm.

[0063] The bandwidth of the rectifying antenna is 1.55-3.61GHz and 5.73-5.83GHz, and the characteristic impedance of the input port of the rectifying antenna is 50Ω. Port 1 can realize broadband capture of radio frequency energy in the environment within the 1.55-3.61GHz frequency band, and ports 2 and 3 can efficiently receive radio frequency energy emitted from a specific location within the 5.73-5.83GHz frequency band. The present invention can collect radio frequency energy in widely popular commercial frequency bands such as GSM-1800, UMTS-2100, ISM-2400, 5G-3500 and WLAN. At the same time, the dual-polarization high-gain antenna subunit in the receiving antenna is combined with a power distribution insensitive rectifier circuit to avoid energy loss caused by polarization adaptation between the receiving antenna and the transmitting source in wireless energy transmission.

[0064] Based on the above structure, the present invention also provides relevant data simulation results.

[0065] Figure 6 and Figure 7 They are the simulation and test results of the parameters of the receiving antenna of the embodiment of the present invention at 1.4-3.8GHz and 5.6-6.0GHz. The values ​​of the return loss of port 1 in the 1.48-3.68GHz band are all less than -10dB, which can indicate that the rectifying antenna receiving antenna has ultra-wideband characteristics in the low frequency band. The return loss of port 2 and port 3 at 5.8GHz is less than -10dB. The transmission coefficient between the three ports of the receiving antenna is less than -25dB within the working frequency band, ensuring that the three ports of the receiving antenna work independently and do not interfere with each other.

[0066] Figure 8 These are simulation and test results of the directional pattern of the receiving antenna at 2.7 GHz when port 1 is excited according to an embodiment of the present invention.

[0067] Fig. 9 The simulation and test results of the gain curve of the receiving antenna of the embodiment of the present invention at 1.4-3.6GHz when port 1 is excited. The vertical axis numbers in the figure represent the gain of the antenna in dBi. The antenna gain has a gain range of 1.2-3.8dBi in the 1.55-3.61GHz band. Combining the two figures, it can be seen that the omnidirectional broadband antenna unit of the receiving antenna has good omnidirectional characteristics in the working frequency band.

[0068] Fig. 9 and Fig.10 The following are the simulation and test results of the antenna gain of the receiving antenna of the embodiment of the present invention at 5.6-6GHz when it is excited at port 1 and port 2 respectively. The ordinate numbers in the figure represent the gain of the antenna in dBi. The antenna gain is 12.7dBi at 5.8GHz, which shows that the dual-polarization high-gain antenna unit of the antenna has good high-gain characteristics.

[0069] Fig.12 and Fig.13 The test results of the rectenna efficiency of the receiving antenna of the embodiment of the present invention at 1.4-3.8GHz and 5.6-6.0GHz are shown respectively. The results show that when the input power is 8dBm, the rectification efficiency of the rectifier circuit in the working frequency band of 1.55-3.61GHz basically reaches more than 50%, and it also has good broadband rectification efficiency at other input power points, indicating that the rectenna has the characteristics of efficient conversion of RF energy into DC energy.

[0070] The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. An omnidirectional broadband high-gain rectifying antenna, characterized in that: It includes an antenna unit radiation structure, an antenna unit radiation patch, an upper dielectric plate, a first rectifier circuit, a second rectifier circuit, a metal plate, a lower dielectric plate, and an antenna unit feeding structure, wherein: The antenna unit radiation structure includes two cross-jointed circuit boards, and an irregular patch structure is provided on the circuit boards; The antenna unit radiation patch includes two cross-connected rectangular patches, and a square slot is provided in the rectangular patch; The first rectifier circuit and the second rectifier circuit are both printed on the upper surface of the upper dielectric plate; The first rectifier circuit is connected to the first port of the antenna unit and is used to receive radio frequency energy in the environment; The second rectifier circuit is connected to the second port and the third port of the antenna unit and is used to receive radio frequency energy from a fixed radio frequency source.

2. The omnidirectional broadband high-gain rectifying antenna according to claim 1, characterized in that: The first rectifier circuit includes a coupled line broadband matching network, a voltage doubler rectifier structure, a first harmonic suppression network, a first filter circuit, a first capacitor and a first resistor. The first capacitor, the coupled line broadband matching network, the voltage doubler rectifier structure, the first harmonic suppression network, the first filter circuit and the first resistor are connected in sequence.

3. The omnidirectional broadband high-gain rectenna according to claim 2, characterized in that: The coupled-line broadband matching network comprises a first microstrip line, a second microstrip line, a third microstrip line, a fourth microstrip line and a fifth microstrip line, wherein: The first microstrip line, the second microstrip line, the third microstrip line, the fourth microstrip line and the fifth microstrip line are connected in sequence; The first microstrip line, the third microstrip line and the fifth microstrip line are parallel; The second microstrip line is perpendicular to the first microstrip line and the third microstrip line respectively; The fourth microstrip line is perpendicular to the third microstrip line and the fifth microstrip line respectively.

4. The omnidirectional broadband high-gain rectifying antenna according to claim 3, characterized in that: The voltage doubler rectifier structure comprises a first diode, a second diode and a sixth microstrip line, wherein: The cathode terminal of the first diode, the anode terminal of the second diode and the second end of the fifth microstrip line are connected; The cathode terminal of the second diode is connected to the first harmonic suppression network; The sixth microstrip line is connected to the positive terminal of the first diode; The sixth microstrip line is also connected to the metal plate through a metal via.

5. The omnidirectional broadband high-gain rectifying antenna according to claim 4, characterized in that: The first harmonic suppression network includes a seventh microstrip line, an eighth microstrip line, a ninth microstrip line and a tenth microstrip line, wherein: The first end of the seventh microstrip line is connected to the cathode end of the second diode, and the second end of the seventh microstrip line is connected to the first end of the eighth microstrip line; The second end of the eighth microstrip line is connected to the first filtering circuit; The ninth microstrip line and the tenth microstrip line are respectively vertically connected to two sides of the eighth microstrip line; The ninth microstrip line has the same structure as the tenth microstrip line.

6. The omnidirectional broadband high-gain rectifying antenna according to claim 5, characterized in that: The first filtering circuit includes a second capacitor, an eleventh microstrip line and a twelfth microstrip line, wherein: The first end of the eleventh microstrip line is connected to the second end of the eighth microstrip line; The second end of the eleventh microstrip line is connected to the first end of the first resistor; The third end of the eleventh microstrip line is connected to the first end of the second capacitor; The second end of the second capacitor is connected to the twelfth microstrip line; The twelfth microstrip line is connected to the metal plate through a metal via.

7. The omnidirectional broadband high-gain rectifying antenna according to claim 6, characterized in that: The second rectifier circuit includes an orthogonal coupler, a parallel rectifier structure, a second harmonic suppression network, a second filter circuit, a third capacitor and a fourth capacitor, wherein: The first end of the orthogonal coupler is connected to the first end of the parallel rectification structure through a third capacitor, and the second end of the orthogonal coupler is connected to the second end of the parallel rectification structure through a fourth capacitor; The parallel rectification structure, the second harmonic suppression network and the second filtering circuit are connected in sequence.

8. The omnidirectional broadband high-gain rectifying antenna according to claim 7, characterized in that: The orthogonal coupler comprises a thirteenth microstrip line, a fourteenth microstrip line, a fifteenth microstrip line, a sixteenth microstrip line, a seventeenth microstrip line, an eighteenth microstrip line, a nineteenth microstrip line, and a twentieth microstrip line, wherein: The thirteenth microstrip line, the fourteenth microstrip line and the fifteenth microstrip line are connected in sequence; The sixteenth microstrip line, the seventeenth microstrip line and the eighteenth microstrip line are connected in sequence; The nineteenth microstrip line is vertically connected to the fourteenth microstrip line and the seventeenth microstrip line, and the twenty-third microstrip line is vertically connected to the fourteenth microstrip line and the seventeenth microstrip line; The fifteenth microstrip line is also connected to the third capacitor; The eighteenth microstrip line is also connected to the fourth capacitor.

9. The omnidirectional broadband high-gain rectifying antenna according to claim 8, wherein the parallel rectifying structure comprises a twenty-first microstrip line, a twenty-second microstrip line, a twenty-third microstrip line, a twenty-fourth microstrip line, a twenty-fifth microstrip line, a twenty-sixth microstrip line, a third diode and a fourth diode, wherein: A first end of the twenty-first microstrip line is connected to the third capacitor; The second end of the twenty-first microstrip line is connected to the first end of the twenty-second microstrip line; The second end of the twenty-second microstrip line is connected to the second harmonic suppression network; The third end of the twenty-second microstrip line is connected to the negative terminal of the third diode; The positive terminal of the third diode is connected to the twenty-third microstrip line, and the twenty-third microstrip line is connected to the metal plate through a metal via; A first end of the twenty-fourth microstrip line is connected to the fourth capacitor; The second end of the twenty-fourth microstrip line is connected to the first end of the twenty-fifth microstrip line; The second end of the twenty-fifth microstrip line is connected to the second harmonic suppression network; The third end of the twenty-fifth microstrip line is connected to the cathode end of the fourth diode; The positive terminal of the fourth diode is connected to the twenty-sixth microstrip line, and the twenty-sixth microstrip line is connected to the metal plate through a metal via.

10. The omnidirectional, broadband, high-gain rectifying antenna according to claim 1, characterized in that: The antenna unit feeding structure is composed of two T-type power dividers.

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