Passive room distribution system monitoring and fault positioning method based on RFID tag

Abstract

The invention discloses a passive indoor distribution system monitoring and fault positioning method based on an RFID tag, and the method comprises the steps: S1, reading the ID information of an RFID tag located at an indoor distribution antenna in an indoor distribution system through an indoor distribution system state monitoring module, and calculating a chain loss value of a link between the indoor distribution system state monitoring module and the RFID tag, uploading a chain loss result to a cloud decision center; and S2, the cloud decision center diagnoses abnormal positions in the indoor distribution system according to the data reported by the indoor distribution system state monitoring module, outputs faulty devices or circuits, generates corresponding alarm work orders, and issues the alarm work orders to installation and maintenance personnel for subsequent equipment maintenance. According to the method, the fault position in the link can be more accurately positioned, the workload of subsequent maintenance personnel is effectively reduced, and the maintenance efficiency is improved. And an existing indoor distribution system is rarely modified, the modification cost is low, and the influence on the original functions of the system is small.

Description

Technical Field

[0001] The invention belongs to the technical field of wireless communication, and in particular relates to a method for monitoring and locating faults of a passive indoor distributed system based on RFID tags. Background Art

[0002] Passive indoor distribution, full name "Passive Indoor Distribution System" (PIDS), consists of combiners, power dividers, couplers, antennas and other devices. It is a technical solution currently used by operators to improve the coverage of wireless signals (2G, 3G, 4G, 5G, etc.) inside buildings. It is mainly used in places where communication and network signals are poor due to complex building structures, material shielding and other reasons, such as large shopping malls, office buildings, underground parking lots, hospitals, etc.

[0003] Most of the equipment in the passive indoor distributed system is passive components, which are low in cost, relatively simple to install, and have higher stability and longer service life. However, because there is no built-in electronic control unit, it is impossible to monitor the working status of each device in the indoor distributed system. When a fault occurs, it is difficult to detect and solve it in time, and subsequent maintenance is difficult. Usually, it can only be tested through customer feedback or by arranging personnel to conduct a "Call Quality Test" (CQT). And because the passive indoor distributed system usually covers a large area and involves many lines, manual detection is time-consuming, inefficient, and difficult to locate the fault. Once a device fails and cannot be reported in time, there will be a problem of delayed abnormal handling, which will affect the customer's network and call quality for a long time.

[0004] At present, the industry generally adopts a solution based on Radio Frequency Identification (RFID) technology. This method can only monitor the continuity of the link from the signal source to the terminal antenna in the passive indoor distribution system, and cannot locate the location of the fault.

[0005] Chinese patent document CN 104463287 A discloses a passive RFID tag-based indoor antenna feed monitoring system and method, including an indoor distribution system, a reader / writer, an RFID tag and a combiner, wherein the indoor distribution system includes a signal source, a power divider, a coupler and an indoor antenna; the reader / writer is arranged in the weak current room where the signal source in the indoor distribution module is located, the reader / writer and the signal source of the indoor distribution system are both connected to the input end of the combiner, the output end of the combiner is connected to the trunk of the indoor distribution system, and the RFID tag is arranged on the outer cover of the indoor antenna; the reader / writer and the signal source are connected to the network management center through the operator network. This technical solution cannot locate the location of the fault.

[0006] Therefore, a method for monitoring each link in a passive indoor distributed system and accurately locating faults is needed to solve the problem that the existing passive indoor distributed system cannot perform status monitoring and has difficulty in locating faults. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a method for monitoring and locating faults of a passive indoor distributed system based on RFID tags, so as to solve the problem that the existing passive indoor distributed system cannot perform status monitoring and has difficulty in locating faults.

[0008] In order to solve the above technical problems, the technical solution adopted by the present invention is: the method for monitoring and locating faults of passive indoor distributed systems based on RFID tags specifically comprises the following steps:

[0009] S1: The ID information of the RFID tag at the indoor antenna in the indoor distributed system is read through the indoor distributed system status monitoring module, and the link loss value of the link from the indoor distributed system status monitoring module to the RFID tag is calculated, and then the link loss result is uploaded to the cloud decision center;

[0010] S2: The cloud decision center diagnoses abnormal locations in the indoor distributed system based on the data reported by the indoor distributed system status monitoring module, outputs the faulty components or lines, and generates corresponding alarm work orders to be sent to the installation and maintenance personnel for subsequent equipment maintenance.

[0011] Preferably, in the indoor distributed system status monitoring module in step S1, a reader / writer, a combiner and an RFID tag are provided, wherein the reader / writer is connected to the passive indoor distributed system through the combiner, and maintains the same level as the signal source, and is connected to the cloud decision center; the RFID tag is placed inside each indoor distributed antenna or on the outer casing of each indoor distributed antenna.

[0012] Preferably, in step S1, the ID information of the RFID tag is read by a reader / writer, and the link loss value of the link between the reader / writer and the RFID tag is calculated, where the link is defined as the line between the reader / writer and the RFID tag and all devices on the line; the reader / writer reads the RFID tag and calculates the link loss value once every fixed time △t seconds, and reports the link loss result, which includes the link loss value, reporting time and abnormal interference.

[0013] Preferably, the specific steps of step S1 are:

[0014] S11: The reader performs a reading operation at a frequency of △t seconds / time, and sends a reading radio wave signal a and a source signal b (a and b have different frequency bands) at a set transmission power Pt;

[0015] S12: The radio wave signal a and the signal source signal b are combined by the combiner, and transmitted together in the subsequent link of the indoor distributed system through the feeder, and finally reach each indoor distributed antenna at the end of the indoor distributed system.

[0016] S13: The indoor antenna transmits the radio wave signal a and the source signal b in the form of radio waves, and the RFID tag outside the indoor antenna absorbs the radio wave signal a sent by the reader, activates the circuit in the RFID tag, and reflects the ID information stored in the RFID tag back to the reader at the starting end of the indoor system;

[0017] S14: The reader calculates the link loss value according to the received signal power Pr and the transmission power Pt, and uploads the link loss value to the cloud decision center.

[0018] Preferably, the RFID tag is composed of a microchip and an antenna, which are packaged in a thin sheet and activated by radio wave energy without a built-in power supply; the chip of the RFID tag stores unique ID information. The size of the RFID tag is 5.5cm*2.5cm.

[0019] Preferably, the indoor antenna includes a directional antenna and an omnidirectional antenna.

[0020] Preferably, in step S2, the link abnormality is divided into link interruption and link interference; if the reader receives the ID information of a certain RFID tag, it means that the link from the reader to the indoor antenna corresponding to the RFID tag is unblocked, that is, there is no fault point; conversely, if the reader does not receive the ID information of a certain RFID tag, it means that the link from the reader to the terminal antenna corresponding to the RFID tag is interrupted; similarly, if the link loss value of a link is greater than the set threshold T, it means that there is abnormal interference in the link.

[0021] Preferably, if there is a link disconnection in step S2, the fault location of each link is determined in turn, specifically:

[0022] S21: Starting from the indoor antenna Z at the end of the interrupted link, query the on / off status of all links belonging to each device on the link in sequence along the link until there are both uninterrupted and interrupted links under a certain device X. In this case, the links from device X (not included) to the indoor antenna Z are likely to be faulty.

[0023] S22: If there is a secondary device Y between device X and indoor antenna Z, and there is only one link under device Y, then a fault may occur in the link from device X (not included) to indoor antenna Z;

[0024] S23: If there is a secondary device Y between device X and indoor antenna Z, and there are multiple links under device Y and all of them are disconnected, if the disconnection time of the links is the same, it is considered that the fault location in the link is between device X (not included) and device Y; if the disconnection time of the links is different, it is considered that the fault location in the link is between device Y (not included) and indoor antenna Z.

[0025] Preferably, in step S2, if all links in the indoor distributed system are interrupted and the link disconnection time is the same, the probability of the fault location in the link being between the reader and the first branch device; otherwise, the fault location in the link is between the first branch device and the indoor distributed antenna.

[0026] Preferably, the indoor distributed system fault location module stores the corresponding relationship between each RFID tag and the indoor distributed antenna and the hierarchical relationship between each device in the indoor distributed system.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) The indoor distributed system status monitoring module in the method for monitoring and locating faults of passive indoor distributed systems based on RFID tags monitors the on / off status of each link in the passive indoor distributed system based on RFID tags. Each RFID tag corresponds to a link in the indoor distributed system, and can timely and accurately monitor link abnormalities.

[0029] (2) The indoor distributed system fault location module in the method for monitoring and fault location of the passive indoor distributed system based on RFID tags not only takes into account the link loss value but also the time when the link abnormality occurs, so as to more accurately locate the location of the fault in the link, effectively reduce the workload of subsequent maintenance personnel, and improve maintenance efficiency;

[0030] (3) Identify the fault point based on the link status. In addition to the link loss value, it also considers the time when the link first becomes abnormal, which can more accurately locate the fault location in the link.

[0031] (4) The RFID tag-based passive indoor distributed system monitoring and fault location method requires little modification to the existing indoor distributed system, has low modification cost, and has little impact on the original functions of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a flow chart of the method for monitoring and locating faults of a passive indoor distributed system based on RFID tags of the present invention; wherein ANT1 to ANTn are indoor distributed antennas, and RFID1 to RFIDn are RFID tags corresponding to the indoor distributed antennas;

[0033] Figure 2An example diagram of the installation of a room-based system of the method for passive room-based system monitoring and fault location based on RFID tags of the present invention;

[0034] Figure 3 This is an example diagram of the installation of an RFID tag in the method for passive indoor system monitoring and fault location based on an RFID tag of the present invention, wherein the RFID tag is pasted on the housing of the indoor antenna. DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and are not intended to limit the protection scope of the present invention.

[0036] Example: Figure 1 As shown, the method for monitoring and locating faults of passive indoor distributed systems based on RFID tags specifically includes the following steps:

[0037] S1: The ID information of the RFID tag at the indoor antenna in the indoor distributed system is read through the indoor distributed system status monitoring module, and the link loss value of the link from the indoor distributed system status monitoring module to the RFID tag is calculated, and then the link loss result is uploaded to the cloud decision center;

[0038] In step S1, the indoor distributed system status monitoring module is provided with a reader / writer, a combiner and an RFID tag. Figure 2 Shown is a diagram of the device architecture of the current embodiment. Figure 2 Line 10 represents the link from the signal source RRU to the indoor antenna ANT10, specifically: signal source RRU>power divider PS1>coupler T21>antenna ANT10; Figure 2 The link represented by Line9 is: signal source RRU>power divider PS1>coupler T21>coupler T22>antenna ANT9; the same applies to links Line1~Line8. Links Line1~Line10 together constitute the entire passive indoor distributed system. On this basis, the reader / writer RW is connected to the passive indoor distributed system through the combiner PI1 and maintained at the same level as the signal source, and the reader / writer RW is connected to the cloud decision center; RFID tags RFID1~RFID10 are respectively attached to the outer shells of the indoor distributed antennas ANT1~ANT10; the reader / writer, combiner and RFID tags together constitute the status detection module of the indoor distributed system;

[0039] The RFID tag is placed inside each room antenna or on the outer shell of each room antenna. Figure 3In the embodiment shown, the RFID tag is set on the housing of the indoor antenna; in the step S1, the ID information of the RFID tag is read by the reader, and the link loss value of the link between the reader and the RFID tag is calculated, and the link is defined as the line between the reader and the RFID tag and all devices on the line; the reader reads the RFID tag and calculates the link loss value once every fixed time △t seconds, and reports the link loss result, which includes the link loss value, reporting time and abnormal interference;

[0040] In this embodiment, the reader is powered by direct current and installed in a weak current room together with a combiner; the reader reads tags and calculates the link loss once every 12 minutes and reports the results;

[0041] The combiner is used to combine the signal of the source and the signal of the reader / writer so as to share a transmission path with the indoor distributed system;

[0042] The RFID tag consists of a microchip and a small antenna encapsulated in a thin sheet and is activated by radio wave energy, without the need for a built-in power source;

[0043] The RFID tag is an ultra-high frequency (UHF) RFID tag with a frequency range of 840-845MHz / 920-925MHz to avoid frequency conflict with the signal source;

[0044] The RFID tag consists of a microchip and an antenna, which are packaged in a thin sheet and activated by radio wave energy without the need for a built-in power supply. The chip of the RFID tag stores unique ID information. The size of the RFID tag is 5.5cm*2.5cm.

[0045] The indoor antenna includes a directional antenna and an omnidirectional antenna;

[0046] The specific steps of step S1 are:

[0047] S11: The reader performs a reading operation at a frequency of △t seconds / time (12 minutes / time), and sends a reading radio wave signal a and a source signal b (a and b have different frequency bands) at a set transmission power Pt;

[0048] S12: The radio wave signal a and the signal source signal b are combined by the combiner, and transmitted together in the subsequent link of the indoor distributed system through the feeder, and finally reach each indoor distributed antenna at the end of the indoor distributed system.

[0049] S13: The indoor antenna transmits the radio wave signal a and the source signal b in the form of radio waves, and the RFID tag outside the indoor antenna absorbs the radio wave signal a sent by the reader, activates the circuit in the RFID tag, and reflects the ID information stored in the RFID tag back to the reader at the starting end of the indoor system;

[0050] S14: The reader calculates the link loss value according to the received signal power Pr and the transmission power Pt, and uploads the link loss value to the cloud decision center;

[0051] Examples of reported data for each link of the room distribution system in this embodiment are shown in Table 1;

[0052] Table 1 Example of link status reporting data for indoor distribution system

[0053] Reporting time Line1 Line2 Line3 … Line10 2024-10-01 00:00:00 12.21dB 18.51dB 25.87dB … 9.89dB 2024-10-01 00:12:00 13.01dB 17.78dB 29.71dB … 10.02dB 2024-10-01 00:24:00 18.22dB 19.26dB 48.56dB … 11.05dB 2024-10-01 00:36:00 15.31dB Null 50.12dB … 10.54dB 2024-10-01 00:48:00 Null Null 49.88dB … 10.86dB … … … … … …

[0054] The data in Table 1 above are Figure 2 The example of link loss data reported in the indoor distribution system is shown. Null in the table means that no RFID information is received.

[0055] S2: The cloud decision center diagnoses abnormal locations in the indoor distributed system based on the data reported by the indoor distributed system status monitoring module, outputs possible faulty devices or lines, and generates corresponding alarm work orders to be sent to installation and maintenance personnel for subsequent equipment maintenance;

[0056] The indoor distributed system fault location module stores the corresponding relationship between each RFID tag and the indoor distributed antenna and the hierarchical relationship between each device in the indoor distributed system; the data reported by the indoor distributed system status monitoring module includes the link loss value and reporting time of each link in the indoor distributed system;

[0057] In step S2, the abnormality of the link is divided into link interruption and link interference; if the reader receives the ID information of a certain RFID tag, it means that the link from the reader to the indoor antenna corresponding to the RFID tag is unblocked, that is, there is no fault point; on the contrary, if the reader does not receive the ID information of a certain RFID tag, it means that the link from the reader to the terminal antenna corresponding to the RFID tag is interrupted; similarly, if the link loss value of a certain link is greater than the set threshold T, it means that there is abnormal interference in the link;

[0058] If there is a link disconnection in step S2, the fault location of each link is determined in turn, specifically:

[0059] S21: Starting from the indoor antenna Z at the end of the interrupted link, query the on / off status of all links belonging to each device on the link in sequence along the link until there are both uninterrupted and interrupted links under a certain device X. In this case, the links from device X (not included) to the indoor antenna Z are likely to be faulty.

[0060] As shown in Table 2 Figure 2 Part of the reported data shows that at time t2, Line 1 is interrupted and Line 2 is unblocked, so the fault location is between the power splitter PS2 (not included) and the antenna ANT1;

[0061] Table 2 Example of link status reporting data for indoor distribution system

[0062] Reporting time Line1 Line2 Line3 … t1：2024-10-01 00:00:00 12.21dB 18.51dB 25.87dB … t2：2024-10-01 00:00:00 NULL 17.78dB 29.71dB … … … … … …

[0063] S22: If there is a secondary device Y between device X and indoor antenna Z, and there is only one link under device Y, then a fault may occur in the link from device X (not included) to indoor antenna Z; Figure 2 In the example, if Line 7 is interrupted and Line 8 is unblocked at a certain moment, the fault location is between coupler T23 (not included) and antenna ANT7;

[0064] S23: If there is a secondary device Y between device X and indoor antenna Z, and there are multiple links under device Y and all of them are disconnected, if the disconnection time of the links is the same, it is considered that the fault location in the link is between device X (not included) and device Y; if the disconnection time of the links is different, it is considered that the fault location in the link is between device Y (not included) and indoor antenna Z.

[0065] As shown in Table 3 Figure 2 In the partial data reported, Line 1 and Line 2 are both interrupted at time t2, while Line 3 is unblocked, so it is considered that the fault location is between coupler T13 (not included) and power divider PS2;

[0066] Table 3 Example of link status reporting data for indoor distribution system

[0067] Reporting time Line1 Line2 Line3 … t1：2024-10-01 00:00:00 12.21dB 18.51dB 25.87dB … t2：2024-10-01 00:12:00 NULL NULL 29.71dB … t3：2024-10-01 00:24:00 NULL NULL 48.56dB … … … … … …

[0068] As shown in Table 4 Figure 2 In the reported data, if the interruption time of Line 1 and Line 2 is different, it is considered that two faults occurred, and the fault locations are between the power splitter PS2 (not included) and the antenna ANT1 and between the power splitter PS2 (not included) and the antenna ANT2;

[0069] Table 4 Example of link status reporting data for indoor distribution system

[0070] Reporting time Line1 Line2 Line3 … t1：2024-10-01 00:00:00 12.21dB 18.51dB 25.87dB … t2：2024-10-01 00:12:00 NULL 17.78dB 29.71dB … t3：2024-10-01 00:24:00 NULL NULL 48.56dB … … … … … …

[0071] Specifically, in step S2, if all links in the indoor distributed system are interrupted and the link disconnection time is the same, the probability of the fault location in the link being between the reader and the first branch device; otherwise, the fault location in the link is between the first branch device and the indoor distributed antenna.

[0072] like Figure 2 As shown, if Line1 to Line10 are disconnected at the same time, it is considered that the fault occurs between the reader RW and the power divider PS1; if Line1 to Line10 are not disconnected at the same time, it is considered that the fault occurs between the power divider PS1 (not included) and each room antenna.

[0073] For ordinary technicians in this field, the specific embodiments are only illustrative descriptions of the present invention. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concepts and technical solutions of the present invention, or the concepts and technical solutions of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A method for monitoring and locating faults in a passive indoor distributed system based on RFID tags, characterized in that: The specific steps include: S1: The ID information of the RFID tag at the indoor antenna in the indoor distributed system is read through the indoor distributed system status monitoring module, and the link loss value of the link from the indoor distributed system status monitoring module to the RFID tag is calculated, and then the link loss result is uploaded to the cloud decision center; S2: The cloud decision center diagnoses abnormal locations in the indoor distributed system based on the data reported by the indoor distributed system status monitoring module, outputs the faulty components or lines, and generates corresponding alarm work orders to be sent to the installation and maintenance personnel for subsequent equipment maintenance.

2. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 1, characterized in that: In step S1, a reader / writer, a combiner and an RFID tag are provided in the indoor distributed system status monitoring module, wherein the reader / writer is connected to the passive indoor distributed system through the combiner, maintains the same level as the signal source, and is connected to the cloud decision center; the RFID tag is placed inside each indoor distributed antenna or on the outer shell of each indoor distributed antenna.

3. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 2 is characterized in that: In step S1, the ID information of the RFID tag is read by the reader / writer, and the link loss value of the link between the reader / writer and the RFID tag is calculated, where the link is defined as the line between the reader / writer and the RFID tag and all devices on the line; the reader / writer reads the RFID tag and calculates the link loss value once every fixed time △t seconds, and reports the link loss result.

4. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 2, characterized in that: The specific steps of step S1 are: S11: The reader performs a reading operation at a frequency of △t seconds / time, and sends a reading radio wave signal a and a source signal b at a set transmission power Pt; S12: The radio wave signal a and the signal source signal b are combined by the combiner, and transmitted together in the subsequent link of the indoor distributed system through the feeder, and finally reach each indoor distributed antenna at the end of the indoor distributed system. S13: The indoor antenna transmits the radio wave signal a and the source signal b in the form of radio waves, and the RFID tag outside the indoor antenna absorbs the radio wave signal a sent by the reader, activates the circuit in the RFID tag, and reflects the ID information stored in the RFID tag back to the reader at the starting end of the indoor system; S14: The reader calculates the link loss value according to the received signal power Pr and the transmission power Pt, and uploads the link loss value to the cloud decision center.

5. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 3 is characterized in that: The RFID tag consists of a microchip and an antenna, which are packaged in a thin sheet and activated by radio wave energy without the need for a built-in power source; the chip of the RFID tag stores unique ID information.

6. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 4, characterized in that: The indoor antenna includes a directional antenna and an omnidirectional antenna.

7. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 4, characterized in that: In step S2, the link abnormality is divided into link interruption and link interference; if the reader receives the ID information of a certain RFID tag, it means that the link from the reader to the indoor antenna corresponding to the RFID tag is unblocked, that is, there is no fault point; On the contrary, if the reader does not receive the ID information of a certain RFID tag, it means that the link from the reader to the terminal antenna corresponding to the RFID tag is interrupted; similarly, if the link loss value of a link is greater than the set threshold T, it means that there is abnormal interference in the link.

8. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 7, characterized in that: If there is a link disconnection in step S2, the fault location of each link is determined in turn, specifically: S21: Starting from the indoor antenna Z at the end of the interrupted link, query the on / off status of all links belonging to each device on the link in sequence along the link until there are both uninterrupted and interrupted links under a certain device X. In this case, the link from device X to the indoor antenna Z may be faulty. S22: If there is a secondary device Y between device X and indoor antenna Z, and there is only one link under device Y, then a fault may occur in the link from device X to indoor antenna Z; S23: If there is a secondary device Y between device X and indoor antenna Z, and there are multiple links under device Y and all of them are disconnected, if the disconnection time of the links is the same, it is considered that the fault location in the link is between device X and device Y; if the disconnection time of the links is different, it is considered that the fault location in the link is between device Y and indoor antenna Z.

9. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 8, characterized in that: In step S2, if all links in the indoor distributed system are interrupted and the link disconnection time is the same, the probability of the fault location in the link being between the reader and the first branch device; otherwise, the fault location in the link is between the first branch device and the indoor distributed antenna.

10. The method for monitoring and locating faults of passive indoor distributed systems based on RFID tags according to claim 8, characterized in that: The indoor distributed system fault location module stores the corresponding relationship between each RFID tag and the indoor distributed antenna and the hierarchical relationship between each device in the indoor distributed system.

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