High-sensitivity ultra-wideband receiving antenna

Abstract

The invention belongs to the technical field of wireless communication, and particularly discloses a high-sensitivity ultra-wideband receiving antenna, which comprises a substrate; the absorbers are formed on the front surface and the back surface of the substrate through copper-clad etching; the width of at least part of each absorber is gradually reduced; the receiver array is formed on the front surface of the substrate through copper-clad etching; the receiving body array comprises a plurality of receiving conductors, all the receiving conductors are sequentially arranged in the direction perpendicular to the extending direction, and the lengths of the receiving conductors in the extending direction are distributed in a geometric progression mode; the feed points are arranged on the substrate and are respectively connected with the wide ends of the absorbers; the feed point is used for transmitting a radio frequency signal received by the receiver array and led out by the absorber; the antenna has the advantages that the broadband antenna is integrated on one board, and multi-antenna switching is omitted; the equal-ratio array seamless frequency splicing is realized, and the gain is flat; trapezoidal absorption is matched with low standing waves; the central feed point loss is small; the device is compact in structure, low in cost, flexible to use, easy to maintain and high in portability.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to a high-sensitivity ultra-wideband receiving antenna. Background Art

[0002] Currently, existing technologies often fail to achieve complete coverage of the ultra-wide frequency range (20MHz to 8000MHz) with a single radio receiver. To meet the signal reception requirements for different frequency bands, a common technical approach is to employ a frequency-segmented design and multi-antenna combination strategy. Specifically, receivers with different structures are constructed for low-frequency, mid-frequency, and high-frequency bands, and then integrated through an RF switching network.

[0003] The main existing technical solutions include: in the low frequency band (20MHz~300MHz), by loading inductive elements (such as inductor coils) or using high magnetic permeability materials, designing structures such as spiral antennas and chopped inverted F antennas to compress the physical size and improve low-frequency reception efficiency; in the medium frequency band (300MHz~3GHz), logarithmic periodic antennas or conical broadband dipole structures are often used to expand the frequency band by utilizing their relatively flat radiation pattern and stable impedance characteristics; in the high frequency band (3GHz~8GHz), gradient slot line structures (such as Vivaldi antennas) or multi-resonant microstrip patch arrays are often used to adapt to the reception characteristics of microwave frequency band signals.

[0004] Although the above technologies perform well within their respective frequency bands, the following problems exist in actual deployment: independent receiving modules are constructed for multiple frequency bands, and the overall device structure is complex and large, making it difficult to integrate into a single substrate or housing, which is particularly unfavorable for portable or rapidly deployed monitoring scenarios; multiple receiving paths involve multiple sets of RF links, front-end tuners and signal processing modules, which increases manufacturing costs and makes subsequent maintenance difficult; relying on a segmented switching mechanism (such as the RF switchmatrix) to switch the receiving path between different frequency bands may introduce additional loss or system delay; the segmented structure is prone to discontinuous receiving performance or gain sag at the frequency junction, making it difficult to meet the requirements for high-fidelity reception of continuous spectrum; currently, there is no integrated receiving antenna solution that can operate continuously in the full frequency range of 20MHz to 8000MHz and have high-gain output.

[0005] Therefore, a high-sensitivity ultra-wideband receiving antenna is proposed to solve the above-mentioned problems. Summary of the Invention

[0006] The present invention aims to provide a high-sensitivity ultra-wideband receiving antenna to solve or improve the above-mentioned technical problem that it is difficult to achieve continuous, high-gain, and high-fidelity signal reception within an ultra-wide frequency range through a single device, resulting in a complex system structure, poor frequency band connection performance and high integration cost.

[0007] In view of this, a first aspect of the present invention is to provide a high-sensitivity ultra-wideband receiving antenna.

[0008] The first aspect of the present invention provides a high-sensitivity ultra-wideband receiving antenna, comprising: a substrate; an absorber, which is formed on the front and back sides of the substrate by copper plating etching; along an extension direction, the width of at least a part of each absorber gradually narrows to perform standing wave suppression and impedance matching for multiple frequency band signals within a preset frequency band; a receiver array, which is formed on the front side of the substrate by copper plating etching; the receiver array includes a plurality of receiving conductors, all of which are arranged in sequence perpendicular to the extension direction, and the lengths of each of the receiving conductors along the extension direction are distributed in a geometric progression to segmentally cover the signal reception range of different frequency bands within the set frequency band; a feeding point, which is arranged on the substrate and is respectively connected to the wide ends of the absorber; the feeding point is used to transmit the radio frequency signal received by the receiver array and led out through the absorber.

[0009] In any of the above technical solutions, the absorber is located on the central axis of the front and back sides of the substrate; two receiving body arrays are provided and are symmetrically arranged on the front side of the substrate with the absorber as the symmetry axis.

[0010] In any of the above technical solutions, within the same receiving body array, equal preset gaps are formed between adjacent receiving conductors; and the value range of the preset gaps is 0.4 mm to 0.5 mm.

[0011] In any of the above technical solutions, with the absorber as the symmetry axis, the length ratio between the receiving conductors at symmetrical positions is a first preset value; the value range of the first preset value is 1.1 to 1.3.

[0012] In any of the above technical solutions, within the same receiver array, the length ratio between adjacent receiving conductors is a second preset value; and the second preset value is in the range of 1.4 to 1.6.

[0013] In any of the above technical solutions, all the receiving conductors are connected to the wide end of the absorber through a horizontal routing conductor, and the horizontal routing conductor is used to merge the signals captured by the receiver array into the feeding point.

[0014] In any of the above technical solutions, the size parameters of the absorber are set according to the preset frequency band range; there is a width ratio between the small end and the large end of the width of the absorber, and the value range of the width ratio is 0.1 to 0.2; the large end of the width of the absorber and the length along the extension direction and the large end of the width have an aspect ratio, and the value range of the aspect ratio is 150 to 200.

[0015] In any of the above technical solutions, a receiver conductor with the largest length in the receiver array is connected to a patch structure through an edge routing conductor; the edge routing conductor extends along the front edge of the substrate, and the patch structure is located on one side of the absorber.

[0016] In any of the above technical solutions, there is a frequency ratio between the highest operating frequency and the lowest operating frequency in the preset frequency band, and the frequency ratio ranges from 305 to 450.

[0017] In any of the above technical solutions, the number of receiving conductors in the two groups of receiving body arrays is set according to the preset frequency band range and in combination with the geometric progression coefficient of the length of the receiving conductors.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] A single-structure receiving antenna is designed to continuously receive multi-band signals over an ultra-wideband range, eliminating the complex switching network required by traditional frequency-dividing multi-antenna combinations. This significantly reduces structural complexity and system size, improving the overall device's portability and rapid deployment capabilities. The geometric progression of conductor lengths within the receiver array allows for continuous splicing of the resonance points of signals in each frequency band, eliminating gain dips at the frequency band boundaries and achieving stable, continuous, and high-fidelity receiving gain characteristics across the entire frequency range. The trapezoidal width gradient structure and symmetrical layout of the absorber effectively achieve standing wave suppression and continuous impedance matching for signals in different frequency bands, avoiding multipath reflections and high-frequency signal distortion, and improving the phase consistency and standing wave stability of the signal output. The feed point is directly connected to the wide end of the absorber, resulting in a compact structure that further reduces signal transmission path losses and improves the energy conversion efficiency of RF signals from the receiving end to the output end. Furthermore, the compact overall structure and PCB etching process reduce the number of RF link components, lowering equipment manufacturing and maintenance costs, making the device more economical and engineering-adaptable.

[0020] Additional aspects and advantages of embodiments according to the present invention will become apparent in the following description or may be learned through practice of embodiments according to the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0022] Figure 1 It is a front schematic diagram of the present invention;

[0023] Figure 2 It is a schematic diagram of the back side of the present invention;

[0024] Figure 3 for Figure 1 Middle A shows the enlarged picture;

[0025] Figure 4 A partial view of the present invention;

[0026] Figure 5 It is a line graph of the standing wave ratio effect of the present invention;

[0027] Figure 6 It is a line graph of the gain effect of the present invention.

[0028] in, Figures 1-6 The corresponding relationship between the reference numerals and component names is as follows:

[0029] 1 substrate, 2 absorber, 201 trapezoidal structure, 202 columnar structure, 3 receiver array, 301 receiving conductor, 4 feeding point, 5 horizontal routing conductor, 6 edge routing conductor, 7 patch structure. DETAILED DESCRIPTION

[0030] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other.

[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0032] See also Figures 1-6 , the following describes a high-sensitivity ultra-wideband receiving antenna according to some embodiments of the present invention.

[0033] The embodiment of the first aspect of the present invention provides a high-sensitivity ultra-wideband receiving antenna. In some embodiments of the present invention, such as Figures 1-6 As shown, the high-sensitivity ultra-wideband receiving antenna includes:

[0034] Substrate 1: Substrate 1 is a printed circuit board (PCB). The PCB is constructed of FR-4 and has double-sided copper cladding. The PCB measures 26.4 mm x 547.4 mm and is 0.8 mm thick. The double-sided copper cladding consists of a top and bottom copper foil, both 0.035 mm thick.

[0035] The absorber 2 is formed on the front and back sides of the substrate 1 by copper coating etching; along one extension direction, the width of at least part of each absorber 2 gradually narrows to suppress standing waves and perform impedance matching on multiple frequency band signals within a preset frequency band.

[0036] The receiving body array 3 is formed on the front surface of the substrate 1 by copper coating etching; the receiving body array 3 includes a plurality of receiving conductors 301, all of which are arranged in sequence perpendicular to the extension direction, and the lengths of each receiving conductor 301 along the extension direction are distributed in a geometric progression to segmentally cover the signal reception range of different frequency bands within the set frequency band.

[0037] The feed point 4 is provided on the substrate 1 and is respectively connected to the wide end of the absorber 2; the feed point 4 is used to transmit the radio frequency signal received by the receiver array 3 and led out through the absorber 2. The soldering pad is soldered to the outer conductor of the coaxial line, such as a braided mesh, copper tube, etc., and the feed point 4 is soldered to the inner conductor (core wire) of the coaxial line. The size of the soldering pad is based on the ability to solder the outer skin of the coaxial line. The gap between the feed point 4 and the soldering pad is 1mm. The trace width of the feed point 4 is 2.6mm and is symmetrical about the center of the board. Directly connected to the feed point 4 and routing upward is the lower half of the top conductor of the absorber; its width is the same as the width of the feed point 4, both 2.6mm. The length of the lower half of the top layer of the absorber is 10.5mm, including the vertical length of the feed point 4 of 0.5mm.

[0038] The present invention provides a high-sensitivity ultra-wideband receiving antenna, the basic component of which is a substrate 1, which is a printed circuit board (PCB) used to support the receiving structure as a whole and serve as the physical carrier of the radio frequency signal conduction path. The PCB uses FR-4 as the dielectric material, which maintains low dielectric loss under high-frequency signal conditions, which is beneficial to improving the signal integrity and environmental stability of the entire receiving device. The PCB is a double-sided copper-clad structure, that is, copper foil layers are applied on both the front and back sides to form two conductive surfaces, the top and bottom layers. The thickness of the copper foil layers is 0.035mm, which has good conductivity and processing stability, and provides a reliable metal path for signal reception, coupling, and transmission. The PCB substrate 1 is an overall narrow and long rectangle with dimensions of 26.4mm×547.4mm and a thickness of 0.8mm. The narrow and long structural design not only meets the requirements of the multi-unit receiving array arrangement, but also takes into account the compact size and mechanical installability of the device. The setting of double-sided copper foil not only allows the functional unit structures to be arranged on the top and bottom layers respectively, but also enables electrical signals to be electrically connected between the upper and lower layers through vias between different layers, thereby achieving spatial distribution optimization on the signal flow path.

[0039] The absorber 2 is formed by etching the copper foil on the front and back sides of the substrate 1, forming an overall symmetrical layout. The absorbers 2 are arranged along the longitudinal extension direction of the substrate 1, and the structure of each absorber 2 presents a gradient width design in this extension direction, that is, its width gradually narrows from one end close to the signal convergence point to the other end away from the feed point 4, forming a non-uniform conductor strip with trapezoidal geometric characteristics. When the broadband signal is injected into the absorber 2 by the receiver array 3, electromagnetic waves of different frequencies will form standing wave responses at different cross-sectional positions of the absorber 2. The absorber 2 effectively realizes a smooth transition from the output impedance of the receiver to the output impedance of the feed point 4 through its continuously changing cross-sectional impedance characteristics. This process can significantly reduce the standing wave ratio (VSWR), reduce signal reflections, and improve the transmission efficiency of the RF signal along the absorber 2.

[0040] Furthermore, because the absorber 2 structure is simultaneously arranged on the front and back of the PCB, with upper and lower conductive connections formed through vias near feed point 4, a closed loop or symmetrical transmission path can be formed while maintaining the overall structural compactness. This achieves balanced compensation for even and odd mode interference over a wide bandwidth, improving the stability of multi-frequency signal coupling. The front and back structures of absorber 2 synergistically participate in signal conduction, enabling effective impedance matching and energy convergence of signals in different frequency bands along the corresponding physical paths.

[0041] The receiver array 3 is formed by etching the copper foil on the front of the substrate 1. Multiple receiving conductors 301 are arranged in sequence along the lateral direction of the substrate 1, that is, perpendicular to the longitudinal direction in which the absorber 2 extends. The receiving conductors 301 are linear conductor structures, evenly spaced on the front of the substrate 1. They are independent of each other but form a linear array as a whole. The entire array is arranged on the left and right sides of the absorber 2 as the symmetry axis, forming a cluster of receiving units with both structural and electrical symmetry. The length of the receiving conductors 301 in the extension direction is set according to a set of geometric progressions, that is, the length ratio between each two adjacent receiving conductors 301 remains within a set coefficient range. This geometric progression structure gives the receiver array 3 segmented selectivity in frequency response: shorter receiving conductors 301 are more sensitive to high-frequency signals, while longer receiving conductors 301 are suitable for receiving low-frequency signals, thereby forming multiple frequency band coverage intervals. In this way, the entire receiving array 3 achieves continuous coverage from low frequency to high frequency in terms of physical structure, ensuring good receiving performance in the ultra-wide frequency band range of 20 MHz to 8000 MHz.

[0042] Each receiving conductor 301 is electrically connected to the absorber 2 via a corresponding horizontal trace, allowing the captured RF signal to be effectively channeled into the absorber 2 path for convergence processing. Because the lengths of the receiving conductors 301 vary gradually and their spacing is structurally stable, the array achieves controlled distribution of electromagnetic response within the frequency band, preventing interference coupling between signals of different frequencies and improving the system's selectivity and stability in multi-frequency environments.

[0043] The feed point 4 structure is arranged on the substrate 1 and is located on the longitudinal center axis of the entire printed circuit board. Its geometric position is precisely aligned with the large width end part of the absorber 2, and is electrically connected through a copper foil conductor. The feed point 4 undertakes the key task of outputting the RF signal from the antenna structure to the external receiving system (such as a front-end amplifier, signal analyzer, etc.), and is an electrical interface node between the internal signal path and the external RF link. Specifically, the feed point 4 is used to weld the inner conductor (core wire) of the RF coaxial cable to achieve the centralized output of the multi-frequency signals converged in the absorber 2. The conductor width of the feed point 4 area is designed to be 2.6mm, and the center of the antenna substrate 1 is used as the symmetry reference. The signal is guided from the large width end of the absorber 2 structure on both sides, and the high-frequency signal is merged and transmitted through the centrally symmetrical feed point 4 path, maintaining the symmetry of the entire structure, helping to reduce the signal offset caused by the imbalance of the dipole electric field and improving the impedance matching performance.

[0044] Connected above the feed point 4 is the lower half of the top copper foil structure of the absorber 2. This structure continues the trace width of the feed point 4, also 2.6mm, and conducts vertically upward. The total length of the conductor in the lower half of this section is 10.5mm, including the overlapping area with the feed point 4 welding. The feed point 4 itself occupies 0.5mm in the vertical direction, forming a continuous and smooth RF path, ensuring that the signal converges from multiple receivers to the absorber 2 via horizontal traces, and is finally introduced to the feed point 4 position efficiently and with low loss through this lower half of the conductor. A 1mm insulation gap is set between the feed point 4 and the soldering pad. This structure is used for physical and electrical isolation, ensuring that the feed point 4 is only connected to the inner conductor part of the coaxial cable, while the soldering pad is located in the outer surrounding area for soldering the outer conductor of the coaxial cable, such as a braided mesh or copper tube. The pad size is designed to fit the outer size of a conventional coaxial connector, ensuring a controllable welding process and a stable mechanical connection. At the same time, by soldering the outer conductor to a pad connected to the ground copper layer, a low-impedance connection is achieved between the antenna system and the reference ground, which is beneficial to the electromagnetic compatibility (EMC) and transmission stability of the entire RF system.

[0045] In summary, by integrating a uniform-length receiver array 3, a symmetrical trapezoidal non-uniform transmission line absorber 2, and a central feed point 4 / pad isolation structure on a single double-sided copper-clad FR-4 PCB, continuous, high-gain signal reception with a bandwidth ratio of approximately 400:1 is achieved from 20 MHz to 8 GHz, fundamentally eliminating the cumbersome traditional band-splitting, multi-antenna, switching network solution. The device is lightweight and easy to deploy, and the internal trapezoidal absorber 2 provides impedance gradient and standing wave suppression across the broadband, eliminating the need for external baluns or matching devices. This significantly reduces RF losses while maintaining high sensitivity and a flat gain curve. The symmetrical layout and 41mm insulation gap between the pad and the feed point combine to suppress common-mode interference, improving electromagnetic compatibility and anti-interference capabilities. With minimal structural components and a one-step board manufacturing process, manufacturing and maintenance costs are significantly reduced. Ultimately, this device provides a truly all-in-one, high-performance, and cost-effective receiving antenna solution for cross-frequency domain scenarios such as spectrum monitoring, mobile communications testing, drone countermeasures, and jewelry quality testing.

[0046] In any of the above embodiments, the absorber 2 is located on the central axis of the front and back sides of the substrate 1 ; two receiver arrays 3 are provided and are symmetrically arranged on the front side of the substrate 1 with the absorber 2 as the symmetry axis.

[0047] In this embodiment, the absorber 2 is placed on the same central axis of the front and back sides of the substrate 1, so that the top and bottom layers form a non-uniform transmission line channel with complete electrical and geometric symmetry, and the high-frequency and low-frequency signals obtain continuous impedance gradient matching in the longitudinal direction; the two groups of receiving body arrays 3 are arranged on the left and right sides with the central absorber 2 as the symmetry axis, which can spatially capture the electromagnetic wave energy incident from the left and right sides in a balanced manner, avoid the directional imbalance caused by unilateral wiring, and equidistantly merge the multi-frequency signals into the central absorber 2 through horizontal routing; the symmetrical structure on the front and back sides suppresses common-mode noise and dipole unbalanced radiation, and the left and right symmetrical arrays offset lateral coupling and mode tilt, thereby achieving a comprehensive operating effect of flat gain curve, symmetrical directivity pattern, low standing wave ratio and consistent signal output phase within the entire 20MHz-8GHz bandwidth.

[0048] Specifically, the absorber 2 includes a gradually narrowing trapezoidal structure 201 and a columnar structure 202 of uniform width, and the columnar structure 202 is connected to the feeding point 4; the trapezoidal structure 201 is connected to the columnar structure 202, and the small end of the width of the absorber 2 is located at the end of the trapezoidal structure 201 away from the columnar structure 202, and the large end of the width of the absorber 2 is located at the end of the columnar structure 202 away from the trapezoidal structure 201.

[0049] Specifically, the coaxial line soldered to the feed point and the top pad is connected to an N-type RF connector, which is then connected to a receiver. The radio waves received by the device are then transmitted to the receiver.

[0050] Specifically, the length of the receiving conductor is shown in the following table:

[0051]

[0052] From the above, it can be seen that the edge spacing between the 11th and 12th receivers is 5 mm.

[0053] In any of the above embodiments, within the same receiver array 3 , equal preset gaps are formed between adjacent receiving conductors 301 .

[0054] The preset gap ranges from 0.4 mm to 0.5 mm, preferably 0.5 mm.

[0055] In this embodiment, the edge gap between adjacent receiving conductors 301 in each receiver array 3 is uniformly set to 0.4mm-0.5mm, achieving a balanced balance of electromagnetic coupling and isolation across the entire 20MHz-8GHz broadband range. The gap is narrow enough to ensure the necessary near-field coupling between adjacent conductors, allowing each receiving conductor 301, designed with equal lengths, to form a continuous, seamless receiving bandwidth in adjacent sub-bands. It is also wide enough to avoid excessive coupling capacitance at the high-frequency end, thereby suppressing crosstalk, standing wave distortion, and gain notch. This uniform gap also maintains the periodic consistency of the array's impedance distribution, balancing the lateral electric field generated by the bilaterally symmetrical array and maintaining a smooth and symmetrical radiation pattern. It also simplifies PCB etching tolerance requirements, improving batch manufacturing consistency and the repeatability of the antenna in different environments.

[0056] In any of the above embodiments, with the absorber 2 as the symmetry axis, the length ratio between the receiving conductors 301 at symmetrical positions is a first preset value.

[0057] The first preset value ranges from 1.1 to 1.3, preferably 1.2.

[0058] In this embodiment, the left and right groups of receiving conductors 301 are arranged in a mirror-image arrangement along the central axis of the absorber 2, and the lengths of the conductors at symmetrical positions are designed to be a fixed ratio of 1.1-1.3. This allows the left and right resonant frequencies to be slightly misaligned without destroying electrical symmetry: when a standing wave dip occurs on the left conductor at a certain frequency, the corresponding conductor on the right is in a relatively high gain region due to its slightly longer (or shorter) length, and vice versa. In this way, the resonance curves on both sides compensate for each other, and the narrowband gain trough that may occur in a single-sided array can be "filled", allowing the antenna as a whole to obtain a flatter amplitude response in the range of 20MHz-8GHz. In addition, the ratio of 1.1-1.3 is small enough not to introduce significant radiation direction deviation or common-mode imbalance, yet large enough to produce the necessary frequency misalignment to achieve bandwidth splicing, thereby comprehensively improving broadband gain continuity, pattern symmetry, and multipath resistance.

[0059] In any of the above embodiments, within the same receiver array 3 , the length ratio between adjacent receiving conductors 301 is a second preset value.

[0060] The second preset value ranges from 1.4 to 1.6, preferably 1.5.

[0061] In this embodiment, broadband continuous splicing is achieved at the electromagnetic resonance mechanism level. Each conductor generates a main resonance point at its corresponding half-wave or quarter-wavelength, and the length ratio is inversely proportional to the resonant frequency ratio. When the ratio is 1.5, the resonant frequency ratio of adjacent conductors is approximately 0.67:1, which is equivalent to an overlapping area of approximately 33% between two adjacent sub-bands; within the ratio range of 1.4-1.6, the overlapping bandwidth remains in an adjustable range of 28%-38%. In this way, the ultra-wide frequency band from 20MHz to 8GHz is divided into several overlapping sub-bands. Whether at the low frequency or high frequency end, adjacent sub-bands can provide a smooth gain transition, without the bandwidth discontinuity or deep depression common in traditional segmented antennas.

[0062] Secondly, a geometric ratio of 1.4-1.6 strikes the optimal balance between coupling strength and isolation. If the length difference is too small, the coupling capacitance at the high-frequency end increases significantly, making the array prone to crosstalk peaks and standing wave fluctuations. If the difference is too large, the sub-band connection is insufficient and the gain curve drops. By controlling the ratio within this narrow range, adjacent conductors maintain the necessary near-field energy coupling to ensure the continuity of low-frequency resonance, while maintaining isolation greater than 10dB in the high-frequency region, suppressing crosstalk and mode tilt. At the same time, the geometric gradient allows the current distribution to change gradually along the array, the main lobe of the directivity pattern shifts smoothly with frequency, and the input impedance curve maintains a good match below -10dB across the entire broadband.

[0063] In any of the above embodiments, all receiving conductors 301 are connected to the wide end of the absorber 2 through the horizontal routing conductor 5 . The horizontal routing conductor 5 is used to transfer the signal captured by the receiver array 3 to the feed point 4 via the absorber 2 .

[0064] From an electrical topology perspective, in this embodiment, the horizontal traces provide transmission paths of nearly identical equivalent length for each receiving conductor 301. This ensures that signal currents excited by different frequency bands have nearly synchronized time delays and phases upon reaching the absorber 2, avoiding phase cancellation or synthesis distortion caused by path differences. Furthermore, the horizontal traces utilize the same copper foil material as the receiving conductors 301, with a uniform line width of 0.5 mm and a fixed length of approximately 11.7 mm. This maintains low distributed inductance and parasitic capacitance across the full bandwidth of 20 MHz to 8 GHz, thereby minimizing transmission losses and maintaining good characteristic impedance continuity.

[0065] The horizontal routing conductor 5 is equivalent to building a broadband current collecting bus at the bottom of the array: the electromagnetic energy captured by the left and right receivers in their respective frequency bands is indiscriminately conducted in parallel through the horizontal routing to the wide end of the absorber 2. Because the trapezoidal structure of the absorber 2 has a gradient impedance characteristic, the multi-frequency signals output by the horizontal routing to the absorber 2 can immediately obtain standing wave suppression and reflection absorption, avoiding the generation of new standing wave peaks and valleys at the convergence point of the conductors. At the same time, the horizontal bus structure limits the distance between the receiver and the absorber 2 to a single PCB plane, reduces the number of vias for cross-layer interconnection, reduces vertical parasitic parameters, and further improves the signal integrity at the high-frequency end (especially in the GHz to 8GHz range). The combined effect is that the receiver array 3 achieves in-phase convergence, low-loss transmission, and integrated impedance matching for the reception gains of signals in different frequency bands, providing support for the antenna to obtain a flat gain curve and low VSWR within the ultra-wideband range.

[0066] In any of the above embodiments, the size parameters of the absorber 2 are set according to a preset frequency band.

[0067] There is a width ratio between the smaller end and the larger end of the absorbent body 2, and the width ratio ranges from 0.1 to 0.2.

[0068] The width of the absorbent body 2 at its larger end and its length along the extension direction have an aspect ratio, and the aspect ratio ranges from 150 to 200.

[0069] In this embodiment, the absorber 2 is designed as a longitudinal trapezoidal non-uniform transmission line, and the dimensions of its two ends are controlled by geometric proportions. This allows it to simultaneously achieve the three key functions of impedance gradient, standing wave suppression, and bandwidth expansion across the entire 20MHz-8GHz wide frequency range. Specifically, the wide end of the absorber 2 connects to the horizontal trace and feed point 4, responsible for converging the multi-frequency signals from the receiver array 3; the narrow end gradually shrinks to 10%-20% of the wide end (width ratio 0.1-0.2), and the lateral gradient from the flare to the tip smoothly transitions the equivalent characteristic impedance from tens of ohms to hundreds of ohms. The reflected waves at the high-frequency end are continuously absorbed in the trapezoid without forming standing wave peaks and valleys at the convergence point, thereby maintaining the VSWR below 2:1 within the broadband and significantly reducing high-frequency spike noise.

[0070] At the same time, the total length of absorber 2 is set to 150–200 times the width of the wide end. This aspect ratio range of 150–200 provides ample electrical travel. For low-frequency signals, a conductor hundreds of millimeters long is equivalent to a progressively loaded λ / 4 transmission line, generating significant inductive reactance in the 20MHz band, compensating for the lack of radiated current at the low-frequency end. For mid- and high-frequency signals, the same conductor exhibits multiple resonance points along the longitudinal direction, absorbing or directing energy at different frequencies at different lengths, effectively breaking up single-point resonance spikes. The long, tapering geometry thus achieves the triple goals of enhancing low-frequency resonance, absorbing high-frequency reflections, and smoothing mid-range impedance.

[0071] Combined with a symmetrical layout of the front and back surfaces, absorber 2 provides progressive matching in the longitudinal direction, forming a common-mode current cancellation channel in the thickness direction. Laterally, its wide end is the same width as the left and right horizontal traces to ensure efficient current convergence. This three-dimensional collaboration enables the highly sensitive ultra-wideband receiving antenna to achieve 400:1 bandwidth coverage on a compact PCB. It features a flat output curve, low standing waves, continuous gain, and a stable radiation pattern, meeting the demanding requirements for "single-device, full-band" reception performance in scenarios such as mobile monitoring and spectrum analysis.

[0072] In any of the above embodiments, the receiver conductor with the largest length in a receiver array 3 is connected to a patch structure 7 via an edge routing conductor 6 ; the edge routing conductor 6 extends along the front edge of the substrate 1 , and the patch structure 7 is located on one side of the absorber 2 .

[0073] In this embodiment, in each receiver array 3, the longest receiving conductor 301, i.e., the one most lateral and best at low-frequency resonance, is led out through an edge routing conductor 6 and connected to a patch structure 7 located on one side of the absorber 2. The edge routing conductor 6 extends along the outermost edge of the front surface of the substrate 1, effectively lengthening the electrical length of the receiving path without occupying the central space within the array. The long conductor itself is sensitive to low-frequency signals, and the additional physical travel provided by the edge routing further lowers its resonant frequency, thereby significantly improving the receiving efficiency in the 20 MHz to approximately 100 MHz range.

[0074] The patch structure 7 connected to the end of the trace has an area much larger than a conventional microstrip conductor, equivalent to loading a planar capacitor at the end of a long conductor. A strong distributed capacitive coupling forms between the incident low-frequency electromagnetic wave and the patch, causing the current to concentrate around the patch, effectively absorbing the low-frequency signal energy and injecting it into the array bus along the edge traces. Because the patch is located on one side of the absorber 2 and connected to the array body via the edge traces, it maintains a sufficient distance from the other receiving conductors 301. This "local electrical extension + side loading" approach does not disrupt the high-frequency current distribution in the center of the array, and also avoids parasitic coupling or pattern distortion in the mid- and high-frequency bands caused by the patch.

[0075] In any of the above embodiments, there is a frequency ratio between the highest operating frequency and the lowest operating frequency in the preset frequency band, and the frequency ratio ranges from 305 to 450.

[0076] In this embodiment, a frequency ratio of 305 to 450 is used as the design benchmark. The proportional length sequence of the receiver array 3 and the trapezoidal impedance gradient curve of the absorber 2 jointly determine the "lowest resonance f_L" and "highest effective resonance f_H." As long as the array endpoint length and the ratio of the narrow end to the wide end of the absorber 2 meet the wavelength mapping corresponding to this ratio, the three-segment combination of array-absorber 2-feed point 4 can maintain a standing wave ratio below 2:1 across the entire bandwidth, achieving seamless reception from long waves to microwaves. Bandwidths exceeding three hundred times are prone to sub-segment gain drops. By constraining the overall bandwidth to 305 to 450, rather than higher or lower, the low-end gain can be maximized while avoiding a sharp increase in high-end losses due to excessive structural inductance, within the feasible conditions of geometric parameters such as patch loading, proportional spacing, and trapezoidal width ratio, resulting in a relatively flat gain curve.

[0077] In any of the above embodiments, the number of receiving conductors 301 in the two groups of receiving arrays 3 is set according to a preset frequency band and in combination with a geometric progression coefficient of the length of the receiving conductors 301 .

[0078] In this embodiment, the lowest and highest frequencies that must be covered are first determined, and then the two outermost receiving conductors 301 are designed to be the longest and shortest conductors that can generate main resonance near these two extreme frequency points; on this basis, the conductors are arranged from one end to the other in a uniform length multiplier increasing (or decreasing) order until the other end, without skipping or missing any conductors. Each additional conductor means inserting a new resonant sub-segment into the spectrum, until the interval between the lowest and highest frequencies is filled end to end with these sub-segments, and the number of conductors ultimately contained in the array is naturally determined. Through this "extreme point first, smooth multiplication" generation strategy, the array presents a continuous and uniform resonant ladder in electromagnetic response: short conductors receive high frequencies, long conductors receive low frequencies, and the frequency bandwidths of adjacent conductors partially overlap but do not overlap excessively. There will be no "black hole" with no gain in a certain frequency range, nor will there be strong coupling distortion at the high end due to overcrowding of conductors. More importantly, the left and right arrays are mirrored in the exact same number and length sequence, with the central absorber 2 as the axis of symmetry, creating both geometric and current symmetry. This ensures balanced radiation across the entire lateral direction, and prevents the main lobe of the antenna pattern from skewed due to structural imbalance. This adaptive generation of antenna lengths also offers significant engineering benefits: if designers need to expand the frequency band to a lower or higher level, they simply need to reset the extreme conductor lengths and continue the arrangement at the same magnification. The array number automatically increases or decreases based on demand, and CAD modeling, PCB etching, and post-commissioning all maintain the same template logic, greatly simplifying new version iterations and cost control.

[0079] Specifically, the number of receiving conductors 301 is determined by the following formula:

[0080]

[0081] Wherein, N is the number of receiving conductors 301 in the receiving array 3; k is the length proportional coefficient of the receiving conductor 301, which ranges from 1.3 to 1.7; f L is the minimum operating frequency; f H When the corresponding frequency band covers 20 MHz to 8000 MHz, the value of N is in the range of 8 to 16, preferably 11.

[0082] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0083] The above embodiments are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A high-sensitivity ultra-wideband receiving antenna, characterized in that: include: substrate; an absorber formed on the front and back surfaces of the substrate by copper coating etching; Along an extension direction, the width of at least a portion of each absorber gradually narrows to perform standing wave suppression and impedance matching on multiple frequency band signals within a preset frequency band; A receiver array is formed on the front surface of the substrate by copper coating etching; the receiver array includes a plurality of receiving conductors, all of which are arranged in sequence perpendicular to the extension direction, and the lengths of the receiving conductors along the extension direction are distributed in a geometric progression to segmentally cover the signal reception range of different frequency bands within the set frequency band; Feeding points are arranged on the substrate and are respectively connected to the wide ends of the absorbers; the feeding points are used to transmit the radio frequency signals received by the receiver array and led out through the absorbers.

2. The high-sensitivity ultra-wideband receiving antenna according to claim 1, characterized in that: The absorber is located on the central axis of the front and back sides of the substrate; two receiver arrays are provided and are symmetrically arranged on the front side of the substrate with the absorber as the symmetry axis.

3. The high-sensitivity ultra-wideband receiving antenna according to claim 2, characterized in that: In the same receiver array, equal preset gaps are formed between adjacent receiving conductors; The preset gap has a value range of 0.4 mm to 0.5 mm.

4. The high-sensitivity ultra-wideband receiving antenna according to claim 2, characterized in that: With the absorber as the symmetry axis, the length ratio between the receiving conductors at symmetrical positions is a first preset value; The first preset value ranges from 1.1 to 1.

3.

5. The high-sensitivity ultra-wideband receiving antenna according to claim 2, characterized in that: In the same receiver array, the length ratio between adjacent receiving conductors is a second preset value; The second preset value ranges from 1.4 to 1.

6.

6. The high-sensitivity ultra-wideband receiving antenna according to claim 2, characterized in that: All the receiving conductors are connected to the wide end of the absorber through a horizontal routing conductor, and the horizontal routing conductor is used to merge the signals captured by the receiver array into the feeding point.

7. The high-sensitivity ultra-wideband receiving antenna according to claim 1, characterized in that: The size parameters of the absorber are set according to the preset frequency band range; There is a width ratio between the smaller end and the larger end of the absorbent body, and the width ratio is in the range of 0.1 to 0.2; The width of the absorbent body at its larger end and the length along the extending direction have an aspect ratio, and the aspect ratio ranges from 150 to 200.

8. The high-sensitivity ultra-wideband receiving antenna according to claim 7, characterized in that: A receiver conductor with the largest length in the receiver array is connected to a patch structure via an edge routing conductor; the edge routing conductor extends along the front edge of the substrate, and the patch structure is located on one side of the absorber.

9. The high-sensitivity ultra-wideband receiving antenna according to any one of claims 1 to 8, characterized in that: There is a frequency ratio between the highest operating frequency and the lowest operating frequency in the preset frequency band, and the frequency ratio ranges from 305 to 450.

10. The high-sensitivity ultra-wideband receiving antenna according to claim 9, characterized in that: The number of receiving conductors in the two groups of receiving body arrays is set according to the preset frequency band range and in combination with the geometric progression coefficient of the length of the receiving conductors.

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