CN118317328A - Networking node system and method based on rapid multi-beam switching technology - Google Patents
Networking node system and method based on rapid multi-beam switching technology Download PDFInfo
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Abstract
The invention provides a networked node system and a method based on a rapid multi-beam switching technology, wherein the system comprises a switch and four sub-nodes, the sub-nodes generate gain directional beams, and the sub-nodes are connected with the switch based on network cables; the switch is capable of sending and receiving instruction information. The system provided by the invention has the capability of a simple phased array, can cover a range of 360 degrees through a plurality of beams, and realizes high gain and full coverage at the same time; the networking node principle model machine consists of 4 sub-nodes, each sub-node covers a 90-degree range through 8 beams, the sub-nodes are connected with a switch through a network cable, and the switch is connected with a computer through the network cable; the computer can monitor the state of each node, and control the nodes to carry out networking, service sending and the like, so that the method has higher practicability.
Description
Technical Field
The invention relates to the technical field of antennas and communication systems, in particular to a networked node system and a method based on a rapid multi-beam switching technology.
Background
In recent years, due to the rapid development of communication technology, more and more fields (such as aerospace, detection, satellite communication, etc.) have higher and higher requirements on communication rate and quality. And the communication node is used as the basis of the communication network and is a precondition for realizing high-speed and high-quality communication. The growing demand has led to a more urgent study of communication nodes in the areas of high gain, wide coverage, etc. The high gain and wide coverage of the beam are constrained by the law of conservation of energy.
Conventional omni-nodes have wide coverage but lower gain. Conventional directional nodes have narrow coverage but high gain. Currently, common solutions to the problems are phased array technology and multi-beam technology. Because of the relatively high cost of phased array technology, its structure is complex and difficult to integrate into small communication devices. While the multi-beam array antenna has the advantages of the phased array antenna, the cost is very low, so that the multi-beam array antenna is more applied to the civil field.
Lee,Woosung,J.Kim,and Y.J.Yoon."Compact Two-Layer Rotman Lens-Fed Microstrip Antenna Array at 24GHz."IEEE Transactions on Antennas&Propagation 59.2(2011):460-466. The fast multi-beam switching technology based on the double-layer microstrip Rotman lens with the working frequency of 24GHz is provided, a lens cavity is arranged at the bottom of a metal layer, an antenna array is arranged at the top of the metal layer, the lens cavity and the antenna array are separated by a common ground plane, and energy is transmitted between the antenna array and the lens cavity through a coupling groove. In addition to the greatly reduced Rotman lens size, the reduction of transmission line length and curvature reduces scattering and unnecessary phase shift due to curvature, improving the performance of the lens in millimeter wave bands; the "true time delay" characteristics of the lens can be unaffected with a significant reduction in lens size. However, this multi-beam antenna technology, without considering the feed network of the antenna, can only be applied to a traveling wave array of series feed. And the radiated electromagnetic wave is linearly polarized, and in some extreme communication scenes, the communication quality is reduced due to multipath effect and faraday rotation effect.
In the Chinese patent document with the publication number of CN117156392A, a code accurate matching system based on a phased array technology is disclosed, which comprises a main control unit, wherein the main control unit is connected with a background computer, a transceiver, a video processing unit and a pseudo base station, the pseudo base station is connected with a pseudo base station antenna, the transceiver is connected with a phased array antenna, the video processing unit is also connected with a camera, under the dispatching of the main control unit, the pseudo base station collects IMSI of surrounding mobile phones, the transceiver is used for measuring the specific spatial position of the mobile phones under the cooperation of the phased array antenna, and the result is marked visually in the output of the video processing unit, so that the final human-shaped image and the mobile phone IMSI accurate matching result are formed. However, the present invention uses a phased array technique, and the present invention uses a multi-beam technique, which is essentially different from the technique used in the patent document.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a networking node system and a method based on a rapid multi-beam switching technology.
The invention provides a networking node system based on a rapid multi-beam switching technology, which comprises:
a switch and four sub-nodes;
The node generates gain directional beams, and the node is connected with the switch based on network cables;
The switch is capable of sending and receiving instruction information.
Preferably, each of the four sub-nodes generates eight gain directional beams and covers a range within ninety degrees of horizontal; the four sub-nodes generate thirty-two beams which cover a range within three hundred sixty degrees horizontally; the working frequency range of the sub-node and the switch comprises 5.5GHz-6GHz.
Preferably, the split node comprises a circularly polarized antenna array, a rotary feed network, a multi-beam forming network based on Rotman lenses, a single-pole eight-throw switch, an AD9361 chip, a control module, a driving module and a power supply module; the circularly polarized antenna array, the rotary feed network, the multi-beam forming network based on the Rotman lens, the single-pole eight-throw switch, the AD9361 chip, the control module, the driving module and the power module are integrated in one aluminum shell, the circularly polarized antenna array and the rotary feed network are arranged on one side, the multi-beam forming network based on the Rotman lens, the single-pole eight-throw switch, the AD9361 chip, the control module, the driving module and the power module are arranged on the other side, and the two sides are vertically interconnected based on radio frequency insulators.
Preferably, the circular polarized antenna array and the rotary feed network both adopt a rotary feed technology; the circularly polarized axial ratio of the gain directional beam in the coverage area is smaller than 3dB.
Preferably, the Rotman lens-based multibeam forming network comprises a lens in the form of a microstrip designed based on geometrical optics; the lens includes eight input ports and eight output ports, and when different ports are input, the output ports generate different phase differences, and then multiple beams are generated.
Preferably, the single-pole eight-throw switch switches the gating switch to a corresponding lens input port after being processed by the control module and the driving module according to a control signal generated by the baseband, and the circularly polarized antenna array is switched to a corresponding gain directional beam.
Preferably, the AD9361 chip comprises a mixer amplifier, a modulator amplifier, a demodulator amplifier, a power amplifier, a low noise amplifier and a single-pole double-throw switch; the single-pole double-throw switch is used as a duplexer to complete the switching of the receiving and transmitting channels.
Preferably, the rotary feed network comprises in the form of a wilkinson power divider and is placed behind a circularly polarised antenna array.
Preferably, the gain-directed beam is based on an adaptive beam steering algorithm that controls the adaptive alignment of the beam to the target node.
The invention provides a networking node method based on a rapid multi-beam switching technology, which comprises the following steps:
step S1: constructing a preset number of sub-nodes;
Step S2: a communication network is established based on the beams generated by the segmented nodes.
Compared with the prior art, the invention has the following beneficial effects:
1. The system provided by the invention has the capability of a simple phased array, can cover a range of 360 degrees through a plurality of beams, and realizes high gain and full coverage at the same time; the networking node principle model machine consists of 4 sub-nodes, each sub-node covers a 90-degree range through 8 beams, the sub-nodes are connected with a switch through a network cable, and the switch is connected with a computer through the network cable; the computer can monitor the state of each node, and control the nodes to carry out networking, service sending and the like, so that the method has higher practicability.
2. The multi-beam forming network based on the Rotman lens has the advantages of low beam scanning cost and easiness in processing, and can realize that the axial ratio of any angle in the beam coverage range of the working frequency band is less than 3dB.
3. The invention has reasonable structure, convenient use and high system integrity, and can be widely applied to the technical fields of antennas and communication systems.
Other advantages of the present invention will be set forth in the description of specific technical features and solutions, by which those skilled in the art should understand the advantages that the technical features and solutions bring.
Drawings
Other features, objects and advantages of the present invention will become more apparent upon reading of the detailed description of non-limiting embodiments, given with reference to the accompanying drawings in which:
FIG. 1 is a system frame diagram of the present invention.
FIG. 2 is a diagram of a system layout and connection relationship of a single split node according to the present invention.
Fig. 3 is a three-dimensional front view of a single minute node of the present invention.
Fig. 4 is a front view of a single minute node of the present invention.
Fig. 5 is a bottom view of a single minute node of the present invention.
Fig. 6 is a block diagram of a multi-beam forming network based on a Rotman lens in accordance with the present invention.
Fig. 7 is a block diagram of a rotary feed network according to the present invention.
Fig. 8 is a schematic diagram of an antenna array excitation layer and a parasitic layer of the present invention.
Fig. 9 is a schematic diagram of the received signal condition of the present invention in a spectrometer.
Fig. 10 is a schematic illustration of multi-beam coverage in accordance with the present invention.
Detailed Description
The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the present invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications could be made by those skilled in the art without departing from the inventive concept. These are all within the scope of the present invention.
Referring to fig. 1, aiming at the defects in the prior art, the invention provides a networking node based on a multi-beam antenna technology in a smart antenna, which has the capability of a simple phased array, and can realize high gain and full coverage simultaneously by covering a 360-degree range by a plurality of beams. The networked node principle prototype consists of 4 partial nodes, each of which covers a 90 ° range with 8 beams. The sub-nodes are connected with the exchanger through network cables, and the exchanger is connected with the computer through the network cables. The computer can monitor the state of each node and control the nodes to carry out networking, service sending and the like.
Referring to fig. 2 and 3, in order to ensure compactness of each node of the networked nodes, a multi-layer board architecture is adopted. The whole node is based on an aluminum housing. The uppermost layer is a parasitic patch layer, down to an air layer, then an excitation patch layer, and the feed network is placed on the back of the excitation patch. In order to reduce the interference of radio frequency and baseband to antenna radiation, the antenna, the radio frequency and the baseband are respectively placed on two sides of an aluminum box, vertical interconnection is realized through radio frequency insulators, and a cavity in the aluminum box provides a wiring space for a feed network. Referring to fig. 4 and 5, the rf and baseband sides are finally sealed by a cover plate, and only one DP9 interface is integrally led out for connecting the network cable and the charging cable.
The working frequency band of the networking node is 5.5GHz to 6GHz, a time division multiplexing system is adopted, and the receiving and transmitting are switched through a single-pole double-throw switch built in a chip AD 9361. Referring to fig. 3, design bits are reserved for PA and LNA at the output end of the multi-beam forming network, where a power amplifier can be added when the subsequent power is insufficient; if the microstrip connection line is not required to be placed here.
The networked node has two processes of transmitting and receiving:
Transmitting: the user sends service information to the appointed partial node through the exchange by the computer. The baseband module of the node generates a baseband signal carrying service information, and the baseband signal is transmitted to the beam switching and receiving and converting module after frequency mixing, modulation and amplification, and meanwhile, the baseband generates a control signal to control the switching of a receiving and transmitting channel and the switching of a beam. The transmit-receive path is switched to the transmit path while the beam is switched to a beam directed to the location of the target node. The whole beam switching process is self-adaptive, and the beam can be self-adaptively aligned to the target node by writing a self-adaptive beam switching protocol in the baseband module. Finally, the radio frequency signal is transmitted to the space through the antenna array, and the service transmission process is completed.
And (3) receiving: the receiving is the inverse of the transmitting, and the service information is transmitted from the target node to the networked node principle prototype and received by a certain sub-node of the networked node principle prototype. And the beam enters the sub-node through the antenna array, and reaches the beam switching and transmitting-receiving conversion module. The baseband module generates control signals to control the switching of the wave beams and the switching of the receiving and transmitting channels. The receiving and transmitting channels are switched to the receiving channels, meanwhile, the wave beams are selected to be directed to the wave beams at the position of the target node, and then the wave beams are transmitted to the user through the switch after frequency mixing, demodulation and amplification of the baseband module.
The invention has reasonable structure, convenient use and high system integrity, realizes the beam scanning based on the multi-beam forming network of the Rotman lens, has low cost and easy processing, and can realize the axial ratio of any angle within the beam coverage range of the working frequency band to be less than 3dB.
The foregoing is a basic embodiment of the present invention, and a further description of the technical solution of the present invention is provided below by means of a preferred embodiment.
Example 1
Referring to fig. 3, a node-dividing housing of the networked node is an aluminum housing of 355mm x 258mm x 35mm dimensions. The upper part of the sub-node is provided with a baseband board, a control board, a Rotman lens, a single-pole eight-throw switch, the lower side is provided with an antenna array and a feed network, and the side surface is provided with a DP9 interface which is a charging port and a network port.
Referring to FIG. 6, a 0.508mm Rogers4350B was used for the dielectric plate. The left side is 8 input ports, and the right side is 8 output ports. The actual measurement result shows that the amplitude fluctuation is less than 3dB and the phase fluctuation is less than +/-15 degrees in the working frequency range of 5.5GHz-6 GHz. The larger amplitude and phase fluctuations will decrease the beam gain and increase the side lobes.
Referring to fig. 7, in the feed network layer, since the antenna array size is 8×8, there are only eight input ports of the lens. Thus, the feed network needs to divide the array into 8 sub-arrays, one for each column, with each feed network being in the form of 1-8. In order to maintain good grounding, a metal ground is placed at a proper distance around the feed network, so that good contact between the ground of the feed network and the metal aluminum box is ensured. Because the system is a public set of antenna for receiving and transmitting, and good matching and port isolation of the feed network are required to be ensured for receiving and transmitting, the feed network adopts the form of a Wilkinson power divider. The metal cavity in the aluminum box reserves the position of the resistor for the wilkinson power divider.
Referring to fig. 8, the patch excitation patch layer and the parasitic patch layer use an ARLON AD250 dielectric plate having a thickness of 0.762 mm. The distance between the parasitic patch and the excitation patch is 4mm, the patch antenna realizes circular polarization through a chamfer, and the impedance bandwidth and the circular polarization bandwidth of the antenna are widened through the parasitic patch. The key problem of realizing circular polarization of the multi-beam antenna is to solve the problem of deterioration of circular polarization with increasing scanning angle and the inability to guarantee circular polarization performance at each angle within the beam range. The present embodiment solves the problem of deterioration of circular polarization in large-angle scanning by using a rotary feeding technique, in which the feeding phases of the patches in odd columns and the patches in even columns are different by 90 ° and the spatial angles are different by 90 °.
Referring to fig. 9, when the prototype of the networked node was operated, the signal was received by the spectrometer, and significant signal levels were observed at 5.5GHz, 5.8GHz and 6 GHz.
Referring to fig. 10, the coverage situation of 32 beams of a networked node at 5.8GHz is described, the 32 beams can cover a horizontal 360 ° range, the highest gain of the beams is 19.1dBi, and no blind spot exists in the coverage area of the beams.
Those skilled in the art will appreciate that the invention provides a system and its individual devices, modules, units, etc. that can be implemented entirely by logic programming of method steps, in addition to being implemented as pure computer readable program code, in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers, etc. Therefore, the system and various devices, modules and units thereof provided by the invention can be regarded as a hardware component, and the devices, modules and units for realizing various functions included in the system can also be regarded as structures in the hardware component; means, modules, and units for implementing the various functions may also be considered as either software modules for implementing the methods or structures within hardware components.
In the description of the present application, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application.
The foregoing describes specific embodiments of the present application. It is to be understood that the application is not limited to the particular embodiments described above, and that various changes or modifications may be made by those skilled in the art within the scope of the appended claims without affecting the spirit of the application. The embodiments of the application and the features of the embodiments may be combined with each other arbitrarily without conflict.
Claims (10)
1. A networking node system based on a rapid multi-beam switching technology comprises a switch and four sub-nodes, and is characterized in that:
The node generates gain directional beams, and the node is connected with the switch based on network cables;
The switch is capable of sending and receiving instruction information.
2. The rapid multi-beam switching technology based networked node system of claim 1 wherein each of the four sub-nodes generates eight gain directed beams and covers a range within ninety degrees of horizontal; the four sub-nodes generate thirty-two beams which cover a range within three hundred sixty degrees horizontally; the working frequency range of the sub-node and the switch comprises 5.5GHz-6GHz.
3. The rapid multi-beam switching technology-based networked node system of claim 1, wherein the split nodes comprise a circularly polarized antenna array, a rotary feed network, a Rotman lens-based multi-beam forming network, a single pole eight throw switch, an AD9361 chip, a control module, a drive module, and a power module; the circularly polarized antenna array, the rotary feed network, the multi-beam forming network based on the Rotman lens, the single-pole eight-throw switch, the AD9361 chip, the control module, the driving module and the power module are integrated in one aluminum shell, the circularly polarized antenna array and the rotary feed network are arranged on one side, the multi-beam forming network based on the Rotman lens, the single-pole eight-throw switch, the AD9361 chip, the control module, the driving module and the power module are arranged on the other side, and the two sides are vertically interconnected based on radio frequency insulators.
4. A networked node system based on a fast multi-beam switching technique according to claim 3, wherein the circularly polarized antenna array and the rotating feed network both employ a rotating feed technique; the circularly polarized axial ratio of the gain directional beam in the coverage area is smaller than 3dB.
5. A networked node system based on fast multi-beam switching technology according to claim 3, characterized in that the Rotman lens based multi-beam forming network comprises lenses in the form of micro-strips designed based on geometrical optics; the lens includes eight input ports and eight output ports, and when different ports are input, the output ports generate different phase differences, and then multiple beams are generated.
6. The rapid multi-beam switching technology-based networked node system of claim 5 wherein the single pole eight throw switch switches the gate switch to the corresponding lens input port and the circularly polarized antenna array to the corresponding gain directed beam after processing by the control module and the drive module according to control signals generated by the baseband.
7. The rapid multi-beam switching technology-based networked node system of claim 3, wherein the AD9361 chip comprises a mixer amplifier, a modulator amplifier, a demodulator amplifier, a power amplifier, a low noise amplifier, and a single pole double throw switch; the single-pole double-throw switch is used as a duplexer to complete the switching of the receiving and transmitting channels.
8. A networked node system based on fast multi-beam switching technology according to claim 3, characterized in that the rotating feed network comprises a form in which wilkinson power dividers are employed and placed behind a circularly polarized antenna array.
9. The rapid multi-beam switching technology based networked node system of claim 1 wherein the gain-directed beam is based on an adaptive beam steering algorithm that controls the beam adaptation to the target node.
10. A method of networking nodes based on a fast multi-beam switching technology, based on the fast multi-beam switching technology of any one of claims 1-9, comprising the steps of:
step S1: constructing a preset number of sub-nodes;
Step S2: a communication network is established based on the beams generated by the segmented nodes.
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