Multi-band receiving antenna system

Abstract

The invention relates to the technical field of wireless communication, and particularly provides a multi-band receiving antenna system. The system comprises a multi-band antenna unit and a feed network which are both arranged on a common dielectric substrate. The multi-band antenna unit comprises at least one low-frequency radiation patch, at least one intermediate-frequency radiation patch and at least one high-frequency radiation patch which are respectively resonated in a first band, a second band and a third band which are not overlapped with each other. The feed network comprises feed branches respectively corresponding to each frequency band, and each branch comprises an impedance matching circuit. The core of the multi-band antenna is that through optimizing the space layout of the radiation patches (for example, the high-frequency patches are arranged in the weak field areas of the low-frequency patches and the intermediate-frequency patches, and the minimum spacing is controlled) and standardizing the wiring spacing of the feed network, the isolation among the multi-band antennas is effectively improved, and signal mutual interference is inhibited. The system is compact in structure, and can support efficient and stable reception of multiple frequency bands in a limited space.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and more specifically, to an antenna system for multi-band reception. Background Technology

[0002] In the evolution of wireless communication technology from 2G to 5G, antenna systems have gradually evolved from simple structures supporting a single frequency band to complex systems covering multiple frequency bands. Early base station antennas could only operate in a single frequency band such as 900MHz or 1800MHz. Later, through dual polarization technology and array integration, antenna arrays that can accommodate multiple frequency bands within a single physical antenna were realized, such as the 4T4R (four transmit, four receive) antenna in the 4G era. Currently, in order to adapt to the collaborative networking of 5G multi-frequency bands (such as 700MHz, 2.6GHz, 3.5GHz, etc.) and the future development of 6G technology, antenna design is further trending towards integration, broadband, and reconfigurability, aiming to achieve efficient coexistence of more frequency bands within a limited space.

[0003] However, existing technologies have significant shortcomings in multi-band antenna integration. When multiple radiating patches (such as low-frequency, mid-frequency, and high-frequency patches) are densely arranged in a limited space, their operating frequency bands often intersect or overlap, easily leading to severe electromagnetic coupling and signal interference. For example, although traditional solutions attempt to improve isolation through filtering circuits or increasing physical spacing, the out-of-band suppression capability of filters is limited for antennas with closely intersecting frequency bands, while increasing spacing is constrained by the miniaturization requirements of equipment, resulting in unsatisfactory decoupling effects. In addition, when the feed network transmits signals of different frequency bands, excessively long parallel traces or insufficient spacing will further exacerbate crosstalk between frequency bands, affecting the overall system performance.

[0004] Therefore, a multi-band receiving antenna system is proposed to address the above problems. The aim is to solve these problems by effectively improving the isolation between multi-band antennas, suppressing mutual interference, and ensuring that each band has stable and good impedance matching characteristics over a wide bandwidth, without significantly increasing the size and complexity of the antenna system. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, embodiments of the present invention provide a multi-band receiving antenna system to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a multi-band receiving antenna system, comprising:

[0007] A multi-band antenna unit, comprising at least one low-frequency radiating patch, at least one intermediate-frequency radiating patch and at least one high-frequency radiating patch disposed on a common dielectric substrate, wherein the low-frequency radiating patch, intermediate-frequency radiating patch and high-frequency radiating patch resonate in a first frequency band, a second frequency band and a third frequency band that do not overlap with each other;

[0008] A power supply network, printed on the dielectric substrate, includes a first power supply branch, a second power supply branch, and a third power supply branch corresponding to the first frequency band, the second frequency band, and the third frequency band, respectively. Each power supply branch includes an impedance matching circuit, and the output terminals of the first power supply branch, the second power supply branch, and the third power supply branch are respectively connected to a signal processing module.

[0009] The spatial arrangement of the low-frequency radiating patch, the mid-frequency radiating patch, and the high-frequency radiating patch on the dielectric substrate is such that the minimum spacing between any two radiating patches is greater than or equal to one-fifth of the effective wavelength of the lower-frequency radiating patch on the dielectric substrate, and the high-frequency radiating patch is arranged in a region where the electromagnetic field intensity generated by the low-frequency radiating patch and the mid-frequency radiating patch is relatively weak.

[0010] Preferably, the impedance matching circuit is an L-type matching network, which includes a parallel capacitor and a series inductor, or a parallel inductor and a series capacitor. The component parameters of the impedance matching circuit are such that the voltage standing wave ratio (VSWR) of the radiating patch in the corresponding frequency band is not greater than 2.0:1 in the target frequency band.

[0011] Preferably, as the transmission lines of the first, second, and third power supply branches extend to the signal output end, the minimum spacing between them perpendicular to the signal transmission direction is greater than or equal to half of the effective wavelength of the center frequency of the highest operating frequency band on the dielectric substrate.

[0012] Preferably, both the low-frequency radiating patch and the mid-frequency radiating patch are rectangular microstrip patches, and their respective frequency bands are tuned by creating concave slots on their patch surfaces.

[0013] Preferably, the high-frequency radiation patch is in the form of annular microstrip patch, and its inner ring is rectangular or circular.

[0014] Preferably, the signal processing module includes a low-noise amplifier group and a filter group. The low-noise amplifier group includes three low-noise amplifiers corresponding to the first frequency band, the second frequency band, and the third frequency band, respectively. The filter group includes three bandpass filters corresponding to the first frequency band, the second frequency band, and the third frequency band, respectively. The output terminals of the first feed branch, the second feed branch, and the third feed branch are respectively connected to the input terminal of the bandpass filter and the input terminal of the low-noise amplifier in sequence.

[0015] Preferably, the signal processing module further includes a control unit, which is used to dynamically enable or disable a corresponding low-noise amplifier in the low-noise amplifier group according to the received signal strength indication.

[0016] Preferably, the dielectric substrate is further provided with an array of isolation strips, which separate the low-frequency radiating patch, the medium-frequency radiating patch and the high-frequency radiating patch from each other.

[0017] Preferably, the first frequency band has a frequency range of 698MHz to 960MHz, the second frequency band has a frequency range of 1710MHz to 2170MHz, and the third frequency band has a frequency range of 3300MHz to 3800MHz.

[0018] The technical effects and advantages of this invention are as follows:

[0019] Compared to existing technologies, this invention arranges high-frequency radiating patches in areas where the electromagnetic field strength generated by low-frequency and mid-frequency radiating patches is relatively weak, and controls the minimum spacing between any two patches to be no less than one-fifth of the effective wavelength of the lower frequency band. This approach utilizes the natural distribution characteristics of the antenna's own radiation field to weaken the inherent coupling between radiating elements of different frequency bands at the electromagnetic field level. It can effectively improve isolation without introducing complex decoupling structures. Its advantages are that it achieves inherent interference suppression under a compact layout, simplifies system design, and enhances reliability.

[0020] Compared to existing technologies, this invention stipulates that the minimum spacing between transmission lines of different frequency band feeder branches, when extending to the signal output end, must be greater than or equal to half of the effective wavelength of the center frequency of the highest operating frequency band. This design rule ensures sufficient spatial isolation for high-frequency signals during transmission in the feeder network, significantly reducing coupling and crosstalk caused by parallel wiring. Its advantage lies in improving the purity of signal transmission, especially ensuring the reception quality of high-frequency signals.

[0021] Compared to existing technologies, this invention employs a rectangular microstrip patch with slots for low-frequency and mid-frequency radiating patches, and a ring-shaped microstrip patch for high-frequency radiating patches. This differentiated structural design allows patches for different frequency bands to more naturally adapt to their frequency characteristics. For example, the ring structure helps high-frequency patches achieve better performance within a limited size. Combined with corresponding impedance matching circuits, this scheme optimizes the resonant characteristics and impedance matching of each frequency band. Its advantages include broadening the operating bandwidth of each frequency band and improving the overall efficiency of the antenna unit. Attached Figure Description

[0022] Figure 1 This is a diagram of the overall system architecture of the present invention.

[0023] Figure 2 This is a schematic diagram of the multi-band antenna unit layout of the present invention.

[0024] Figure 3 This is a power supply network and isolation design diagram for the present invention.

[0025] Figure 4 This is a flowchart of the signal processing and control process of the present invention. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1

[0028] As attached Figures 1-4 The multi-band receiving antenna system shown begins its design with the selection of the dielectric substrate. As the physical carrier of the entire system, the substrate's performance parameters directly determine the effectiveness of the antenna radiating patch and the feed network. Typically, FR-4 epoxy glass cloth laminate or Rogers 4350B high-frequency board with a dielectric constant between 2.2 and 4.5 is selected, with a thickness controlled within the range of 0.5 mm to 1.6 mm. The substrate size should be determined based on the space constraints of the terminal equipment; for mobile terminal applications, a typical size is 100 mm long × 50 mm wide. The loss tangent of the substrate material should be as low as possible (e.g., less than 0.0025) to ensure high radiation efficiency at high frequencies and reduce energy loss during signal transmission.

[0029] After selecting the substrate, the design and layout of the multi-band radiating patches proceed. According to the design requirements, the system needs to cover three non-overlapping frequency bands: low frequency (698-960MHz), mid-frequency (1710-2170MHz), and high frequency (3300-3800MHz). Each frequency band corresponds to one or more radiating patches, whose shape, size, and layout collectively determine the antenna's resonant characteristics and radiation performance. The low-frequency radiating patch adopts a rectangular microstrip patch form, and its initial length L_L can be approximately determined by the following formula:

[0030]

[0031] Where c represents the speed of light (3 × 10^8 m / s), f_L is the center frequency of the low-frequency band (e.g., 829 MHz), ε_eff is the effective dielectric constant of the substrate, and ΔL is the length correction factor considering edge effects. The mid-frequency radiating patch also adopts a rectangular design, but by creating a concave slot on the patch surface, additional inductive and capacitive coupling is introduced, effectively reducing the patch's physical size and allowing it to resonate in the mid-frequency band. The high-frequency radiating patch uses a ring-shaped microstrip structure, utilizing the multimode resonance characteristics of the ring structure to cover a wider frequency band. The difference between the inner and outer diameters of the ring is approximately one-tenth of the high-frequency wavelength λ_H in the substrate, i.e., Δr = λ_H / (10√ε_eff), where λ_H = c / f_H, and f_H is the center frequency of the high-frequency band (e.g., 3550 MHz).

[0032] The spatial arrangement of radiating patches is crucial for reducing inter-band interference. According to electromagnetic field theory, the coupling between radiating patches is inversely proportional to their spacing. To reduce coupling, the minimum spacing d_min between any two radiating patches must satisfy the following condition:

[0033]

[0034] Where λ_low represents the effective wavelength on the dielectric substrate of the patch operating at the lower frequency band among two closely spaced radiating patches. Simultaneously, the high-frequency radiating patch should be placed in an area where the electromagnetic field intensity generated by the low-frequency and mid-frequency radiating patches is relatively weak. This location can be determined by simulating and analyzing the field distribution on the substrate surface using electromagnetic simulation software (such as ANSYS HFSS or CST Microwave Studio). For example, in a rectangular substrate layout, the low-frequency patch is often placed in the upper left region, the mid-frequency patch in the lower right region, and the high-frequency patch in the mid-field region between the former two. The specific location needs to be repeatedly optimized in simulations.

[0035] The design of the feed network is another core aspect of the system design. The feed network consists of microstrip lines printed on a dielectric substrate, including three feed branches corresponding to the low, mid, and high frequency bands, respectively. Each branch contains an impedance matching circuit, typically an L-type matching network, composed of parallel capacitors and series inductors, or parallel inductors and series capacitors. The component values ​​of the matching network need to be calculated using the following formula to ensure that the voltage standing wave ratio (VSWR) of the antenna in the target frequency band does not exceed 2.0:1:

[0036]

[0037] Where Z_in is the antenna input impedance, Z_L is the equivalent impedance of the radiating patch, ω is the angular frequency, and L and C are the matching inductance and capacitance values, respectively. To reduce crosstalk between feed branches of different frequency bands, the minimum spacing s_min between each branch transmission line as it extends to the signal output terminal, perpendicular to the signal transmission direction, must satisfy the following:

[0038]

[0039] Where λ_high is the effective wavelength of the center frequency of the highest operating frequency band (i.e., the high frequency band) on the dielectric substrate. The wiring of the power supply network should avoid sharp angle turns and use arcs or 45-degree bevel transitions to reduce signal reflection caused by impedance discontinuities. For longer traces, grounding vias should be set periodically to suppress common-mode resonance.

[0040] After completing the preliminary design, electromagnetic simulation software is needed to verify and optimize the overall design. During simulation, key indicators such as S-parameters (especially S11 return loss and S21 isolation), radiation pattern, gain, and efficiency should be closely monitored. For example, the S11 of the low-frequency patch should be below -10dB at 825MHz, the mid-frequency patch should meet the same requirement at 1940MHz, and the high-frequency patch should have a return loss better than -15dB at 3550MHz. Simultaneously, the isolation (S21) between any two frequency bands should be below -20dB within the operating frequency band to ensure that each band operates independently without interference. Simulation optimization is an iterative process that may require adjustments to patch size, slot structure, matching network parameters, or layout position until all performance indicators meet the design requirements. The final simulation results should generate a detailed report, including data on electric field distribution, surface current, and radiation pattern, to provide a basis for subsequent manufacturing stages.

[0041] 2 Manufacturing Process Stage

[0042] The manufacturing process is a crucial step in transforming the design into a physical antenna, requiring precision machining techniques and strict quality control. This stage begins with the manufacture of the printed circuit board (PCB), the physical carrier of the antenna system. The manufacturing process first involves transferring the designed radiating patch and feed network pattern onto a copper-clad dielectric substrate using photolithography. The substrate material is procured according to the specifications selected in the design phase, commonly using FR-4 epoxy glass cloth laminate or high-frequency Rogers material. During the pattern transfer process, the accuracy of linewidth and spacing must be strictly controlled, especially for high-frequency microstrip lines, where the width tolerance should be maintained within ±0.05 mm to ensure the stability of the characteristic impedance. Subsequently, an etching process is used to remove excess copper foil, forming the desired circuit pattern.

[0043] After etching, a via metallization process is performed on the dielectric substrate. Holes are drilled at predetermined locations using a CNC drilling machine; the hole diameter is typically between 0.2 mm and 0.5 mm. A conductive layer is then formed on the hole walls using chemical deposition or direct electroplating to achieve electrical connections between different layers. These vias serve not only as signal vias but also as ground vias, which are crucial for suppressing crosstalk and maintaining signal integrity. In particular, ground via arrays surrounding high-frequency radiating patches can effectively suppress surface wave propagation and improve antenna gain and front-to-back ratio. After via metallization, a solder resist layer, typically a green or black photosensitive ink, is applied to the circuit surface to prevent short circuits during subsequent soldering and to protect the circuit from environmental influences.

[0044] Next, component soldering and antenna unit assembly are performed. Surface mount technology (SMT) is used to precisely mount passive components such as capacitors and inductors in the impedance matching circuit to their predetermined positions. For mass production, a fully automated placement machine is used to complete this process, ensuring the accuracy and consistency of component placement. Soldering employs a reflow soldering process, using precise temperature profile control to melt the solder paste and form a reliable connection. After soldering, the antenna unit and feed network are integrated. Since the radiating patch is printed on the substrate along with the feed network, this step mainly involves connecting the antenna system to external signal processing modules. Coaxial connectors (such as SMA or IPEX interfaces) are typically used, soldered to the signal output terminal of the feed network, and securely connected to the substrate ground plane via ground pads.

[0045] Quality control is implemented throughout the entire manufacturing process. Inspection is required after each critical step. Key inspection items include: linewidth accuracy, dielectric thickness, dielectric constant uniformity, metal layer conductivity, and solder joint quality. For antenna performance, a vector network analyzer (VNA) can be used to sample and measure S-parameters to verify whether return loss and isolation match simulation results. Only products that pass rigorous inspection can proceed to the next process or leave the factory. Data accumulated during manufacturing, such as actual machining values ​​of critical dimensions and material parameter fluctuations, should be recorded and fed back to the design team for optimizing subsequent design versions.

[0046] For cases requiring special treatment of high-frequency radiation patches, such as annular microstrip patches, special attention must be paid to the precision control of the inner and outer diameters of the ring during the manufacturing process. A high-precision CNC milling machine can be used to make fine adjustments to the patch area to ensure the symmetry and dimensional accuracy of the annular structure.

[0047] If the design includes a slotted structure (such as the U-shaped slot of an intermediate frequency patch), laser cutting technology must be used to ensure that the edges of the slot are smooth and neat, avoiding electric field concentration caused by sharp angles, thereby improving power capacity and reliability.

[0048] The ultimate goal of the manufacturing process is to produce antenna systems that fully meet design specifications, have consistent performance, and are reliable.

[0049] 3. Testing and Verification Phase

[0050] The testing and verification phase is a crucial step in ensuring that the actual performance of the antenna system meets the design requirements. It requires a series of precise measurements and rigorous analyses to verify various system indicators. This phase mainly includes three parts: simulation verification, prototype testing, and performance optimization. Professional instruments and standard procedures are used to comprehensively evaluate the antenna system. The testing process must be conducted in a microwave anechoic chamber to eliminate environmental electromagnetic waves and reflection interference, ensuring the accuracy of the measurement results.

[0051] Simulation testing and verification is the first step in the testing phase, aiming to predict antenna performance through computer simulation. A three-dimensional model of the antenna system is built using high-frequency electromagnetic simulation software (such as ANSYS HFSS or CST Studio Suite), setting boundary conditions and excitation ports that match actual conditions. Simulation analysis mainly focuses on S-parameters, radiation field, and impedance characteristics. S11 (return loss) in the S-parameters reflects the impedance matching of the antenna in each target frequency band. It is required that the S11 value be below -10dB (i.e., voltage standing wave ratio VSWR ≤ 2:1) in each target frequency band (low frequency 698-960MHz, mid frequency 1710-2170MHz, high frequency 3300-3800MHz). Isolation (S21, S31, etc.) measures signal leakage between antenna ports in different frequency bands and must be below -20dB to ensure effective isolation between frequency bands. Radiation field simulation generates a three-dimensional radiation pattern of the antenna, calculating key performance indicators such as gain, front-to-back ratio, and half-power beamwidth. Simulation can help identify design flaws in advance, such as resonant frequency shift, insufficient isolation, or low gain, and provide a reference for subsequent actual measurements.

[0052] After simulation verification, the prototype sample testing phase begins. An antenna prototype is fabricated according to the design drawings and mounted on a test stand, connected to a vector network analyzer (VNA) via an RF coaxial cable. The VNA measures the antenna's S-parameters, first performing single-port calibration (such as SOLT calibration) to eliminate errors introduced by the test cable and connectors.

[0053] Subsequently, the S11 parameters of each port are measured sequentially to check whether the actual impedance matching of each frequency band meets the requirements, and the resonant frequency (the frequency corresponding to the minimum S11 value) and -10dB impedance bandwidth are recorded. If the measured resonant frequency deviates from the design target (e.g., the offset exceeds 2%), compensation is required by fine-tuning the size of the radiating patch (e.g., cutting part of the edge or adding conductive tape) or adjusting the matching network component values. After completing the impedance matching adjustment, the S-parameters (S21, S31, S32, etc.) between all ports are measured to verify whether the isolation meets the standard. If the isolation is insufficient, the layout of the radiating patch and the spacing of the power supply network wiring need to be checked to ensure they conform to the design rules, and adjustments should be made if necessary.

[0054] Radiation performance testing: In a microwave anechoic chamber, the antenna prototype is mounted on a rotatable platform and connected to a signal source and a spectrum analyzer (or receiver). The signal source transmits a continuous wave signal at a specific frequency, which is received by the antenna under test. The rotating platform is controlled to rotate the antenna in the horizontal (azimuth) and vertical (elevation) planes, and the received signal power at different angles is recorded to plot the antenna's two-dimensional and three-dimensional radiation patterns. Parameters such as antenna gain, beamwidth, sidelobe level, and front-to-back ratio can be read from the radiation patterns. For omnidirectional antennas, the roundness of the horizontal plane radiation pattern is of particular concern; for directional antennas, the main lobe pointing and gain must be verified to meet design requirements. Furthermore, the antenna efficiency, i.e., the ratio of radiated power to input power, must be calculated, and it should be higher than 50% in all frequency bands (ideally exceeding 70%).

[0055] System-level testing: Integrate the antenna prototype with the designed signal processing module (including low-noise amplifiers, filters, etc.) to form a complete receiving system. Measure the system's received bit error rate (BER) and receiver sensitivity by transmitting standard test signals (such as QPSK or 16QAM modulated signals) to verify the antenna system's performance in real-world operating scenarios. Simultaneously, conduct multi-band concurrent operation tests to evaluate whether intermodulation interference or sensitivity degradation issues exist when the system receives signals from multiple frequency bands concurrently.

[0056] Performance optimization and iteration are integral to the entire testing phase. By comparing and analyzing simulation and experimental results, the root causes of performance deviations are identified. These could be due to material parameter errors, processing accuracy limitations, or improper model simplification. To address the root cause, design parameters are modified or manufacturing processes are adjusted, and new prototypes are created for verification. For example, if the high-frequency gain is insufficient, the width of the ring patch or the feed point position can be optimized; if the low-frequency bandwidth is too narrow, methods such as coupled feeding or adding parasitic patches can be considered to extend the bandwidth. The optimization process may require multiple iterations until all performance indicators meet or exceed design requirements.

[0057] The final deliverable of the testing and verification phase is a detailed test report, which includes all simulation and measured data, performance parameter tables, radiation patterns, photographs, and records of optimization measures.

[0058] 4. Installation, Deployment and Maintenance Phase

[0059] The installation, deployment, and maintenance phase is a crucial transitional stage for multi-band receiving antenna systems from laboratory environments to real-world applications. The quality of its execution directly affects whether the system can achieve its expected performance in the preset working environment. This phase requires adherence to systematic processes and standards to ensure that the antenna system is correctly installed, accurately debugged, and continuously maintained to guarantee its long-term stable operation.

[0060] The installation of an antenna system begins with determining a suitable installation location. The selection of the installation location must comprehensively consider the electromagnetic environment, mechanical stability, and accessibility. Priority should be given to locations far from strong interference sources (such as large motors, high-voltage cables, and radar stations) to avoid electromagnetic interference to the received signal. Simultaneously, the installation location should have a clear field of view, ensuring there are no significant physical obstructions between the antenna and the target signal source (such as a base station or satellite), especially since obstacles in the direction of low-frequency signal propagation can significantly attenuate signal strength. The antenna is typically fixed to a wall, column, or tower using a bracket. The bracket must have sufficient mechanical strength and corrosion resistance (e.g., using hot-dip galvanized steel or aluminum alloy materials) to withstand wind loads from the local maximum wind speed, preventing the antenna from deviating from its pointing direction due to swaying or tilting. During installation, a compass or Global Positioning System (GPS) is used to assist in adjusting the approximate azimuth angle of the antenna, aligning it with the direction of the signal source. For example, for directional communication, the antenna's main lobe should be aligned with the target base station; for omnidirectional coverage, the antenna's vertical polarization direction should be perpendicular to the ground.

[0061] The wiring and connection of the feeder network are crucial aspects of the installation process. Connect the antenna system's output ports to the signal processing module (i.e., the receiver) using low-loss coaxial cables (such as RG-6 or LMR-400). The cable length should be as short as possible to minimize signal attenuation during transmission, especially at higher frequencies (such as 3.5GHz), where cable loss increases significantly with frequency. When wiring, avoid sharp bends in the cable; the bending radius should generally be no less than 10 times the cable's outer diameter to prevent damage to the internal cable structure, which could lead to impedance mismatch and signal reflection. Cable joints (such as SMA, N-type, or F-type) must be properly waterproofed and dustproofed using self-adhesive tape or heat-shrink tubing to prevent moisture intrusion that could cause poor contact or corrosion. If the system contains multiple antenna units (such as diversity reception or MIMO systems), the cable lengths between units should be consistent to ensure signal synchronization.

[0062] After physical installation, the system debugging and fine-tuning phase begins. A vector network analyzer (VNA) or portable spectrum analyzer is used to monitor the signal quality at the antenna ports. The azimuth and elevation angles of the antenna are fine-tuned, and signal strength indicators (such as the Received Signal Strength Index (RSSI) or the peak signal on the spectrum analyzer) are observed. Once the strongest signal is found, the antenna bracket is locked. During debugging, it is necessary to verify that each frequency band is functioning correctly: The signal reception within the center frequency and bandwidth of the low-frequency, mid-frequency, and high-frequency bands is tested sequentially to confirm that each band can effectively capture signals without interference. If the system includes a control unit in the signal processing module (used for dynamically managing low-noise amplifiers), its functionality also needs to be verified: Simulate different signal strength conditions (such as using an adjustable attenuator) to check whether the control unit can correctly enable or disable the amplifiers for the corresponding frequency bands to optimize system power consumption and receiving dynamic range.

[0063] Lightning protection and grounding measures are crucial for ensuring the long-term stable operation of the system in harsh environments. As outdoor equipment, antennas, especially when located at the highest point of a building, are susceptible to damage from lightning strikes or induced overvoltages. Therefore, reliable lightning protection devices must be installed. The antenna's metal bracket and the outer conductor of the coaxial cable should be connected to the building's existing lightning protection strip or independent grounding electrode via a copper core grounding wire with a cross-sectional area of ​​not less than 6 square millimeters.

[0064] The grounding resistance should be less than 10 ohms to ensure that lightning current can be quickly discharged to the ground. A signal surge arrester (composed of a gas discharge tube or transient voltage suppression diode) should be installed at the entrance where the cable enters the room. Its operating frequency must cover all frequency bands of the antenna system, and the insertion loss should be less than 0.5dB to avoid affecting normal signal transmission.

[0065] System acceptance and documentation archiving mark the completion of the installation and deployment phase. During acceptance, key performance parameters of the antenna system in each frequency band must be measured and recorded, such as the received level at the center frequency, signal-to-noise ratio (SNR), and voltage standing wave ratio (VSWR). These parameters must be compared with design specifications and test reports to ensure that the performance meets the standards after installation. At the same time, detailed installation documentation must be prepared, including installation location diagrams, wiring diagrams, grounding resistance test records, and debugging data.

[0066] Post-construction maintenance and continuous monitoring are essential for ensuring the long-term reliable operation of the antenna system. A regular maintenance plan should be established, with routine inspections typically conducted every six months or a year.

[0067] Maintenance includes: checking antenna brackets and fixing bolts for looseness or corrosion, tightening or replacing them if necessary; checking cable joint seals for integrity and signs of water ingress or oxidation; retesting grounding resistance to ensure the grounding system is effective; and cleaning dust, bird droppings, and other debris from the radome surface to maintain cleanliness. For critical applications, a remote monitoring system can be established to monitor parameters such as the received signal level and bit error rate at the antenna port in real time. When performance indicators become abnormal (such as a continuous drop in signal level or a surge in bit error rate), the system automatically alarms, prompting maintenance personnel to troubleshoot promptly, such as checking for loose connectors, damaged cables, or new external interference sources. Through preventative maintenance and proactive monitoring, the probability of system failure is minimized, extending service life.

[0068] The installation, deployment, and maintenance phase is the final stage in transforming antenna system design results into practical application value. Through standardized installation, meticulous debugging, and continuous maintenance, the multi-band receiving antenna system is ensured to operate stably and efficiently throughout its life cycle, providing users with reliable wireless signal reception services.

[0069] According to the above implementation process, the complete implementation process of the multi-band receiving antenna system covers the entire process from theoretical design to actual deployment. Through system design, precise manufacturing process, comprehensive testing and verification, and standardized installation and maintenance, the antenna system can achieve efficient multi-band collaborative operation in a limited space and maintain long-term operational reliability.

[0070] Finally, the following points should be noted: First, in the description of this application, it should be noted that, unless otherwise specified and limited, the terms "installation", "connection", and "linkage" should be interpreted broadly, and can be mechanical or electrical connections, or internal connections between two components, or direct connections. "Up", "down", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may change.

[0071] Secondly: The accompanying drawings of the embodiments disclosed in this invention only involve the structures involved in the embodiments disclosed in this invention. Other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of this invention can be combined with each other.

[0072] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-band receiving antenna system, characterized in that, include: A multi-band antenna unit, comprising at least one low-frequency radiating patch, at least one intermediate-frequency radiating patch and at least one high-frequency radiating patch disposed on a common dielectric substrate, wherein the low-frequency radiating patch, intermediate-frequency radiating patch and high-frequency radiating patch resonate in a first frequency band, a second frequency band and a third frequency band that do not overlap with each other; A power supply network, printed on the dielectric substrate, includes a first power supply branch, a second power supply branch, and a third power supply branch corresponding to the first frequency band, the second frequency band, and the third frequency band, respectively. Each power supply branch includes an impedance matching circuit, and the output terminals of the first power supply branch, the second power supply branch, and the third power supply branch are respectively connected to a signal processing module. The spatial arrangement of the low-frequency radiating patch, the mid-frequency radiating patch, and the high-frequency radiating patch on the dielectric substrate is such that the minimum spacing between any two radiating patches is greater than or equal to one-fifth of the effective wavelength of the lower-frequency radiating patch on the dielectric substrate, and the high-frequency radiating patch is arranged in a region where the electromagnetic field intensity generated by the low-frequency radiating patch and the mid-frequency radiating patch is relatively weak.

2. The multi-band receiving antenna system according to claim 1, characterized in that, The impedance matching circuit is an L-type matching network, which includes a parallel capacitor and a series inductor, or a parallel inductor and a series capacitor. The component parameters of the impedance matching circuit ensure that the voltage standing wave ratio (VSWR) of the radiating patch in the corresponding frequency band is no greater than 2.0:1 in the target frequency band.

3. The multi-band receiving antenna system according to claim 1, characterized in that, As the transmission lines of the first, second, and third power supply branches extend to the signal output end, the minimum spacing between them perpendicular to the signal transmission direction is greater than or equal to half of the effective wavelength of the center frequency of the highest operating frequency band on the dielectric substrate.

4. The multi-band receiving antenna system according to claim 1, characterized in that, Both the low-frequency radiating patch and the mid-frequency radiating patch are rectangular microstrip patches, and their respective frequency bands are tuned by creating concave slots on their patch surfaces.

5. The multi-band receiving antenna system according to claim 4, characterized in that, The high-frequency radiation patch is in the form of a ring-shaped microstrip patch, and its inner ring is rectangular or circular.

6. The multi-band receiving antenna system according to claim 1, characterized in that, The signal processing module includes a low-noise amplifier group and a filter group. The low-noise amplifier group includes three low-noise amplifiers corresponding to the first frequency band, the second frequency band, and the third frequency band, respectively. The filter group includes three bandpass filters corresponding to the first frequency band, the second frequency band, and the third frequency band, respectively. The output terminals of the first feed branch, the second feed branch, and the third feed branch are connected sequentially to the input terminals of the bandpass filters and the input terminals of the low-noise amplifiers.

7. The multi-band receiving antenna system according to claim 6, characterized in that, The signal processing module further includes a control unit, which is used to dynamically enable or disable a corresponding low-noise amplifier in the low-noise amplifier group based on the received signal strength indication.

8. The multi-band receiving antenna system according to claim 1, characterized in that, The dielectric substrate is also provided with an array of isolation strips, which separate the low-frequency radiation patch, the medium-frequency radiation patch and the high-frequency radiation patch from each other.

9. The multi-band receiving antenna system according to claim 1, characterized in that, The first frequency band has a frequency range of 698MHz to 960MHz, the second frequency band has a frequency range of 1710MHz to 2170MHz, and the third frequency band has a frequency range of 3300MHz to 3800MHz.

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