Safety wireless communication method and system for inclined elevator based on internet technology

Abstract

The application relates to the technical field of digital information transmission, in particular to a safety wireless communication method and system for an inclined elevator based on an internet technology, which comprises the following steps: a WIFI communication network is established in an area where the inclined elevator is located, and an evaluation period is preset; first characteristic values and second characteristic values of each link in each period are obtained, the third characteristic values of each link are obtained by combining the total throughput of all routers in each link and the average total queuing delay of data packets; the communication link from the inclined elevator to the main gateway in each period is recorded as a main link; whether each main link is congested is measured; the link measurement results of each link in the current period are obtained when the main link is congested and not congested respectively; and routing selection is performed according to an OSPF protocol. The application aims to respond to network changes in time, select the optimal transmission path, ensure that higher-priority transmission guarantee is provided for the safety wireless communication of the inclined elevator, and further ensure the real-time performance of the safety monitoring of the inclined elevator.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of digital information transmission, in particular to a safety wireless communication method and system for inclined elevators based on Internet technology. BACKGROUND

[0002] An inclined elevator is a special elevator that runs along an inclined track. It achieves inclined movement through track design and is widely used in complex terrain scenic spots, such as mountain tourist areas and ski resorts. Due to the special operating environment of the inclined elevator, the early features of potential faults, such as track deformation, are weak and cannot be directly detected from sensor-collected data. Therefore, the current inclined elevator operating data is transmitted in real time to a cloud monitoring platform based on Internet wireless communication, potential faults are identified through data analysis algorithms, and timely braking is performed to reduce safety hazards. However, when the number of visitors in the scenic spot increases, the communication pressure of the Internet increases dramatically, and even network congestion occurs, which affects the transmission of inclined elevator operating data and reduces the real-time safety monitoring of the inclined elevator.

[0003] Publication No. CN117640380A discloses a wireless router transmission rate switching method and system. The core of this method is to dynamically adjust the communication frequency band and transmission path of the device through topology analysis, space-time signal analysis, neural network prediction, genetic optimization, and rate compensation, thereby optimizing network performance. However, this method is too complex when adjusting the transmission path, and when the network is congested in the scenic spot, the large amount of calculation may cause a delay in responding to network changes. Moreover, this method does not fully consider the characteristics of large operating range and large differences in wireless communication environments at different locations of the inclined elevator, and the wireless network topology structure constructed by this method cannot accurately describe the wireless signal transmission characteristics of the elevator at different locations, which affects the effectiveness of subsequent transmission path optimization. In addition, this method does not fully consider the different needs of different types of devices in the network environment of the scenic spot, and cannot provide a transmission strategy that prioritizes the safety wireless communication of the inclined elevator. Ultimately, this method cannot guarantee the real-time safety monitoring of the inclined elevator. SUMMARY

[0004] In view of the above, it is necessary to provide a safety wireless communication method and system for inclined elevators based on Internet technology, which can respond to network changes in a timely manner, select the optimal transmission path, and ensure that the safety wireless communication of the inclined elevator is prioritized for transmission protection, thereby ensuring the real-time safety monitoring of the inclined elevator:

[0005] In a first aspect, the present application provides a safety wireless communication method for inclined elevators based on Internet technology, which includes the following steps:

[0006] a WIFI communication network is established in the area where the diagonal elevator is located, and an evaluation period of each link in the WIFI communication network is preset, which is referred to as a period;

[0007] A first characteristic value of each link is obtained by a signal strength of a transmission signal of a first wireless router in each link within each period at a mobile terminal and a number of mobile terminals connected by the first wireless router;

[0008] A second characteristic value of each link is obtained by the number of mobile terminals connected by each wireless router in each link, in combination with a growth of the number of mobile terminals connected by each wireless router and a throughput within each period and a preset number of periods before each period;

[0009] A third characteristic value of each link is obtained by the first characteristic value and the second characteristic value, and a total amount of throughputs of all routers in each link and a total amount of average queuing delays of data packets.

[0010] Each main link is recorded from a communication link of the diagonal elevator to a main gateway in the WIFI communication network within each period, and whether each main link is congested is measured by an average queuing delay of data packets of a wireless router in each main link; if the main link is not congested within a previous period, the third characteristic value of each link in a current period is taken as a link metric result of each link within the current period; otherwise, a metric value of the main link in the current period is obtained by a difference amount of an average level of the average queuing delay of data packets of all wireless routers in the main link within the previous period compared with a preset delay threshold and the third characteristic value of the main link within the previous period; a link metric result of each link within the current period is obtained by the third characteristic value of each link within the current period and the metric value.

[0011] Routing is selected according to the OSPF protocol by the link metric result.

[0012] In one embodiment, the first characteristic value is a normalized value of a ratio of the number of mobile terminals connected by the first wireless router to the signal strength.

[0013] In one embodiment, the second characteristic value is obtained by:

[0014] A previous continuous preset number of periods adjacent to each period and each period are taken as each reference evaluation period of each period; throughputs of each wireless router in each link within all reference evaluation periods of each period are arranged in time sequence to form a throughput sequence of each wireless router in each period; and a slope of a fitting straight line of each throughput sequence is obtained.

[0015] obtaining a difference between the number of mobile terminals connected by each wireless router in each link in a first reference evaluation period and the number of mobile terminals connected by each wireless router in a last reference evaluation period;

[0016] The second characteristic value can be further obtained by the slope, the difference and the number.

[0017] In one embodiment, the second characteristic value is calculated by:

[0018] calculating a ratio of the difference and the number, and taking the inverse of the ratio and the slope as the exponent of an exponential function with a preset number greater than 1 as the base number to obtain an inverse proportional mapping result of the ratio and a direct proportional mapping result of the slope;

[0019] calculating a product of the inverse proportional mapping result and the direct proportional mapping result;

[0020] The second characteristic value is the average of the product of all wireless routers in each link.

[0021] In one embodiment, the third characteristic value is obtained by:

[0022] calculating a sum of the throughputs of all wireless routers in each link;

[0023] calculating an accumulated value of the average queuing delay of data packets of all wireless routers in each link;

[0024] The third characteristic value is positively correlated with the first characteristic value, the second characteristic value, the sum and the accumulated value, respectively.

[0025] In one embodiment, the third characteristic value is calculated by:

[0026] calculating a product of a normalized value of the sum, the first characteristic value and the second characteristic value;

[0027] calculating a normalized result of the inverse of the accumulated value;

[0028] The third characteristic value is the ratio of the product and the normalized result.

[0029] In one embodiment, the method for measuring whether each primary link is congested is:

[0030] calculating an average value of the average queuing delay of data packets of all wireless routers in each primary link, and determining that each primary link is not congested if the average value is less than or equal to a preset delay threshold, otherwise, determining that each primary link is congested.

[0031] In one embodiment, the obtaining process of the metric value is:

[0032] obtaining a ratio of the difference value and a preset time delay threshold, taking the ratio as an index of an exponential function with a natural constant as a base, and obtaining an exponential function mapping result of the ratio;

[0033] the metric value is a product of the exponential function mapping result and a third characteristic value of the main link in the previous period.

[0034] In one embodiment, the obtaining of the link metric result of each link in the current period by the third characteristic value of each link in the current period and the metric value comprises:

[0035] for each link other than the main link in the previous period in the current period, taking the third characteristic value of each link in the current period as the link metric result of each link in the current period;

[0036] for the main link in the previous period in the current period, identifying the sending end of the data packet by the IP protocol, and when the sending end of the data packet is the diagonal elevator, taking the metric value as the link metric result of the main link in the previous period in the current period;

[0037] when the sending end of the data packet is a mobile terminal other than the diagonal elevator, taking the third characteristic value of the main link in the previous period in the current period as the link metric result of the main link in the previous period in the current period.

[0038] In a second aspect, the embodiments of the present application further provide an Internet technology-based diagonal elevator safety wireless communication system, which comprises a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor implements the steps of the Internet technology-based diagonal elevator safety wireless communication method according to any one of the above embodiments when executing the computer program.

[0039] The present application has at least the following beneficial effects:

[0040] The application can monitor the network state regularly, and discover potential problems in time through the preset evaluation period. The first characteristic value can reflect the communication load and signal transmission reliability of the link by calculating the signal strength of the first wireless router in the link at the mobile terminal and the number of connected mobile terminals. The second characteristic value can accurately reflect the change trend of the communication load of the link by considering the actual communication load and potential communication load of the link. The communication state of the link can be quantified comprehensively by the first characteristic value, the second characteristic value, the total throughput and the average total queuing delay of data packets, which is beneficial to preferentially selecting the link with less unsaturated communication state in route selection, so as to realize load balancing and avoid network congestion.

[0041] Further, the average queuing delay of the main link can be monitored to discover whether the main link is congested in time. If the main link is congested, the link metric result of the main link is adjusted to avoid further aggravating the congestion of the main link. The load distribution and dynamic route selection are performed according to the link metric result of each link. On the one hand, the network fluctuation and network congestion problem caused by unfair route selection can be avoided under the condition that the network is relatively stable. On the other hand, when the network is congested, higher priority transmission guarantee can be provided for the safety wireless communication of the inclined elevator, thereby ensuring the real-time performance of the safety monitoring of the inclined elevator. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, and the advantages thereof, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor based on these drawings.

[0043] Figure 1 The step flow chart of the inclined elevator safety wireless communication method based on Internet technology provided by an embodiment of the present application is shown in the figure.

[0044] Figure 2 The acquisition flowchart of the third characteristic value is shown in the figure. DETAILED DESCRIPTION

[0045] In the description of the embodiments of the present application, the words such as "exemplary", "or", "for example" are used to represent an example, illustration or description. Any embodiment or design scheme described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as more preferred or more advantageous than other embodiments or design schemes. Rather, the words such as "exemplary", "or", "for example" are intended to present the relevant concept in a specific manner.

[0046] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. It is to be understood that the use of "a", "an" or "the" herein is merely open-ended and is intended to represent "one or more" unless otherwise stated.

[0047] It should also be noted that the terms "first", "second" in the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence.

[0048] The specific scheme of the Internet technology-based inclined elevator safety wireless communication method and system provided by the present application will be described in detail below in combination with the drawings.

[0049] Please refer to Figure 1 which shows the step flowchart of the Internet technology-based inclined elevator safety wireless communication method provided by an embodiment of the present application, which comprises the following steps:

[0050] Step 1: A WIFI communication network is established in the area where the inclined elevator is located.

[0051] The present application establishes a WIFI communication network in the area where the inclined elevator is located based on Internet technology, ensures that the elevator can stably communicate with the cloud monitoring platform during operation, and realizes timely identification of potential faults.

[0052] Firstly, a wireless router supporting 802.11ac or higher standards is installed near the inclined elevator track as a wireless access point (AP) to ensure high bandwidth and stability of the inclined elevator safety wireless communication.

[0053] Secondly, the signal coverage range of each AP is tested using WIFI analysis tools such as NetSpot to ensure that the inclined elevator can connect at least 3 APs at any position to meet the network redundancy requirement.

[0054] Finally, a wireless router is installed at the starting station of the inclined elevator as the main gateway, which is connected to the cloud monitoring platform. At the same time, a static IP address is set for the wireless router as the main gateway to ensure that it can communicate with the cloud server, and the OSPF dynamic routing protocol is enabled between all APs to realize automatic routing optimization of the subsequent network.

[0055] A wireless terminal device such as a wireless network card is installed inside the inclined elevator to access the WIFI communication network. At the same time, an encoder is installed at the elevator drive wheel of the inclined elevator to obtain the moving distance of the inclined elevator by recording the number of rotations and direction, and then the position of the inclined elevator is transmitted to the cloud monitoring platform in real time through the WIFI communication network.

[0056] From the diagonal elevator starting station, the diagonal elevator track is evenly divided into track sections with equal lengths. In this embodiment, the length of the track section is 20 m, and the implementer can set the length of the track section according to the actual situation, and the application does not make special restrictions. For each track section, the midpoint of the track section is recorded as its reference position, and the signal strength of the accessible AP at the reference position is obtained for subsequent switching of the diagonal elevator wireless terminal device and the AP near the track.

[0057] Step 2, preset the evaluation period of each link in the WIFI communication network. For each evaluation period, the communication state of each link is measured by the throughput of each wireless router in the link, the average queuing delay of data packets, and the number of connected mobile terminals.

[0058] In the network environment of the scenic diagonal elevator, when the network is congested due to increased human flow, the state of different links can be evaluated by monitoring the performance indicators of the AP, and the dynamic routing selection of the OSPF protocol can be adjusted based on the link state of the WIFI communication network. Specifically, the evaluation period is set to 1 s in this embodiment, and the implementer can set the specific value of the evaluation period according to the actual situation, and the application does not make special restrictions. The throughput of the wireless router in the evaluation period, the average queuing delay of data packets, and the number of connected mobile terminals are used as performance indicators for evaluating the state of different links.

[0059] Unlike general communication networks, on the one hand, the diagonal elevator has a large operating range, and the number of network switches in the WIFI communication network during one operation is large, so a more stable network switch is needed. On the other hand, the passenger flow of the scenic area where the diagonal elevator is located changes quickly, which directly affects the change of the communication state of different links.

[0060] The network performance indicators are collected by the wireless router and uploaded to the cloud monitoring platform. The cloud server dynamically adjusts the link measurement strategy of the network according to the changes in its performance indicators, and distributes different link measurement results to each wireless router through the WIFI communication network to reduce frequent network switching, avoid network congestion, and improve network stability.

[0061] Step 2.1, the first characteristic value of each link is obtained by the signal strength of the first wireless router in each link in each period at the mobile terminal and the number of mobile terminals connected by the first wireless router.

[0062] First, for any link in the WIFI communication network, the first characteristic value of the any link in the current evaluation period is obtained by the signal strength of the first wireless router in the any link at the mobile terminal and the number of mobile terminals connected by the first wireless router in the any link, and the expression is:

[0063] In the formula, Fa represents the first characteristic value of any link in the current evaluation period; norm() represents a normalization operation; N represents the number of mobile terminals connected to the first wireless router in the any link; and R represents the signal strength of the transmission signal of the first wireless router in the any link at the mobile terminal. The wireless routers are numbered according to their order in the link.

[0064] In this embodiment, the Min-Max normalization method is used to normalize the The characteristic coefficient of the any link is recorded as the characteristic coefficient of the any link. According to the characteristic coefficients of all links in the current evaluation period, the normalized value of the characteristic coefficient of each link in the current evaluation period is obtained by using the formula of the Min-Max normalization method. The formula of the Min-Max normalization method is well known and will not be described herein.

[0065] It should be noted that the smaller the first characteristic value obtained by calculation, the smaller the communication load between the first link and the mobile terminal thereof, and the higher the reliability of signal transmission.

[0066] The first characteristic value of each link in each evaluation period is calculated by using the same calculation method as the first characteristic value of the any link in the current evaluation period.

[0067] In step 2.2, the second characteristic value of each link is obtained by using the number of mobile terminals connected to each wireless router in each link, in combination with the growth of the number of mobile terminals connected to each wireless router and the throughput in each period and the preset number of periods before each period.

[0068] For any evaluation period, the previous continuous preset number of evaluation periods adjacent to the any evaluation period and the any evaluation period are taken as respective reference evaluation periods of the any evaluation period for analyzing the change trend of the link communication state. When the number of previous evaluation periods of the any evaluation period is insufficient, the throughput, the average queuing delay of packets and the number of connected mobile terminals in the missing reference evaluation period are supplemented according to the throughput, the average queuing delay of packets and the number of connected mobile terminals in all reference evaluation periods of the any evaluation period respectively by using Newton interpolation method. The Newton interpolation method is a known technology and will not be described herein. It should be noted that for the first evaluation period, since there is only one reference evaluation period with data in the first evaluation period, the Newton interpolation method cannot be applied, and therefore the same value as the throughput in the first evaluation period is used to supplement the throughput in the missing reference evaluation period of the first evaluation period, and the above supplement method is used to supplement the average queuing delay of packets and the number of connected mobile terminals in the missing reference evaluation period of the first evaluation period.

[0069] In the embodiment, the number of respective reference evaluation periods of the any evaluation period is 300, and the number of reference evaluation periods can be limited by the implementer according to the actual situation, and the application does not make special limitation.

[0070] On the one hand, the throughput of the wireless router in the any link reflects the communication load of the any link, and when the throughput of the wireless router increases, the communication load of the any link rises. On the other hand, the number of connected mobile terminals of the wireless router in the any link reflects the potential communication load of the any link, and when the number of connected mobile terminals of the wireless router increases, the potential communication load of the any link rises. When the growth rate of the throughput and the number of connected mobile terminals of the wireless router is faster, the communication load of the any link is more affected by the passenger flow.

[0071] The application arranges the throughputs of the wireless routers in the any link in the current evaluation period in all reference evaluation periods in sequence to form a throughput sequence of the wireless routers in the any link in the current evaluation period. A fitting straight line of each throughput sequence is obtained, and the slope of the fitting straight line is calculated to reflect the change trend of the throughput of the wireless router. The calculation method of the slope of the fitting straight line is a known technology and will not be described herein.

[0072] In this embodiment, the least square method is used to obtain the fitting straight line of each throughput sequence. Specifically, for each throughput sequence, each element in the throughput sequence and its sequence number in the throughput sequence form each data point, where the sequence number is the horizontal coordinate and the element is the vertical coordinate. All data points corresponding to the throughput sequence are input into the least square method, and the fitting straight line of all data points is output. The least square method is a known technology, and will not be described herein. As other embodiments, on the basis of being able to measure the fitting straight line of each throughput sequence, implementers can use other existing technologies such as weighted least square method, and the present application does not make special limitations.

[0073] The second characteristic value of the any link in the current evaluation period is obtained by combining the number of mobile terminals connected by each wireless router in the any link in the current evaluation period, the growth of the number of mobile terminals connected by each wireless router in all reference evaluation periods, and the growth of the throughput of each wireless router in all reference evaluation periods, and is used to reflect the degree of change of the communication state of the link caused by the change of passenger flow in the scenic area where the diagonal elevator is located. The expression is:

[0074] In the formula, Fb represents the second characteristic value of the any link in the current evaluation period; M represents the number of wireless routers in the any link; exp() represents an exponential function with a natural constant as the base, which is used to map and to positive numbers; represents the difference between the number of mobile terminals connected by the mth wireless router in the first reference evaluation period of the current evaluation period and the number of mobile terminals connected in the last reference evaluation period; represents the number of mobile terminals connected by the mth router in the current evaluation period; represents the slope of the fitting straight line of the throughput sequence of the mth router in the current evaluation period. The exponential function with a natural constant as the base is only one embodiment of the present application. As other embodiments, the implementer can set the specific value of the base as long as the base of the exponential function is a preset number greater than 1, and the present application does not make special limitations.

[0075] It should be noted that the greater the second characteristic value calculated is, the more obvious the rise of the communication load of the any link is, and the closer the communication state of the link is to saturation.

[0076] The second characteristic value of each link in each evaluation period is calculated by using the same calculation method as the second characteristic value of the any link in the current evaluation period.

[0077] Step 2.3, obtaining the third characteristic value of each link by the first characteristic value and the second characteristic value, and the sum of the throughputs of all routers in the link and the sum of the average queuing delays of data packets.

[0078] It is considered that when the network is in a light load state, the queue is almost empty, and thus the queuing delay tends to be zero. When the network approaches a saturation state, the queuing phenomenon significantly increases, resulting in a sharp increase in the queuing delay. Further increase in the queue length can result in more delay and even packet loss.

[0079] The passenger flow near the inclined elevator in the scenic area changes rapidly. The instantaneous increase in the passenger flow causes a sharp increase in the communication pressure of the wireless router. When the wireless router approaches congestion, only the throughput cannot timely reflect the change in the communication pressure of the network link under the scenario. The present application utilizes the nonlinear change of the queuing delay under the light load state and the saturation state of the wireless router to improve the sensitivity of the link metric, so that the subsequent route selection can timely respond to the network change.

[0080] Based on the above analysis, the third characteristic value of any link in the current evaluation period is obtained by the first characteristic value and the second characteristic value of the link in the current evaluation period, the sum of the throughputs of all routers in the link in the current evaluation period, and the sum of the average queuing delays of data packets of all routers in the link in the current evaluation period, which is used to quantify the communication state of the link, and the expression is:

[0081] In the expression, Fc represents the third characteristic value of any link in the current evaluation period; norm() represents a normalization operation; Fa represents the first characteristic value of any link in the current evaluation period; Fb represents the second characteristic value of any link in the current evaluation period; Ta represents the sum of the throughputs of all routers in any link in the current evaluation period; exp() represents an exponential function with a natural constant as the base number, which is used to normalize (-Da); and Da represents the sum of the average queuing delays of data packets of all routers in any link in the current evaluation period.

[0082] In the embodiment, the Min-Max normalization method is used to normalize Ta; according to the sum of all links in the current evaluation period, the normalized value of the sum of each link in the current evaluation period is obtained by the formula of the Min-Max normalization method, wherein the formula of the Min-Max normalization method is a known content, and thus the present application will not be described in detail.

[0083] It should be noted that the sum of the throughputs of all routers in the any link in the current evaluation period can reflect the actual load capacity of the any link, the higher the throughput, the closer the communication network to saturation, and the third eigenvalue of the any link calculated is larger; the smaller the third eigenvalue calculated, the better the any link, and the wireless router in the any link should be selected in subsequent routing selection through the OSPF protocol to achieve load balancing and avoid network congestion. The acquisition process of the third eigenvalue is shown in the schematic diagram of Figure 2

[0084] The third eigenvalue of each link in each evaluation period is calculated by using the same calculation method as the third eigenvalue of the any link in the current evaluation period.

[0085] Step 3, the communication link of the diagonal elevator to the main gateway in the WIFI communication network in each period is recorded as each main link; the average queuing delay of the data packets of the wireless router in each main link is used to measure whether each main link is congested; if the main link is not congested in the previous period, the third eigenvalue of each link in the current period is used as the link metric result of each link in the current period; otherwise, the difference between the average level of the average queuing delay of all wireless routers in the main link in the previous period and the preset delay threshold, and the third eigenvalue of the main link in the previous period are used to obtain the metric value of the main link in the current period; the link metric result of each link in the current period is obtained by using the third eigenvalue of each link in the current period and the metric value; routing selection is performed according to the OSPF protocol by using the link metric result.

[0086] In the first evaluation period of the WIFI communication network, the third eigenvalue of each link in the first evaluation period is used as the link metric result of each link in the first evaluation period, and routing selection is performed according to the OSPF protocol.

[0087] For the communication link of the diagonal elevator to the main gateway, the average value of the average queuing delay of the data packets of all wireless routers in the communication link of the diagonal elevator to the main gateway in each evaluation period is calculated, and when the average value is less than or equal to the preset delay threshold, it is determined that the communication link of the diagonal elevator to the main gateway in each evaluation period is not congested. In the next evaluation period of each evaluation period, the third eigenvalue of each link in the next evaluation period is still used as the link metric result of each link in the next evaluation period, and routing selection is performed according to the OSPF protocol; wherein the communication link of the diagonal elevator to the main gateway in the WIFI communication network in each evaluation period is recorded as the main link in each evaluation period.

[0088] ​When the average value is greater than the preset delay threshold, it is determined that the communication link of the inclined elevator to the main gateway is congested in each evaluation period, the transmission time of data in the WIFI communication network is increased, at this time, the link metric result needs to be weighted to realize load redistribution to guarantee the safe wireless communication of the inclined elevator, taking the current evaluation period as an example, if the communication link of the inclined elevator to the main gateway is congested in the previous evaluation period of the current evaluation period, the difference between the average level of the average queuing delay of the data packet of all wireless routers in the communication link of the inclined elevator to the main gateway in the previous evaluation period and the preset delay threshold, and the third characteristic value of the communication link of the inclined elevator to the main gateway in the previous evaluation period are used to obtain the metric value of the communication link of the inclined elevator to the main gateway in the current evaluation period, and the expression is:

[0089] ; in the formula, indicates the metric value of the communication link of the inclined elevator to the main gateway in the current evaluation period; indicates the average value of the average queuing delay of the data packet of all wireless routers in the communication link of the inclined elevator to the main gateway in the previous evaluation period, which reflects the network congestion degree of the communication link of the inclined elevator to the main gateway; exp() indicates an exponential function with a natural constant as a base, which is used to rapidly increase the metric value of the communication link of the inclined elevator to the main gateway in the initial stage of network congestion, so as to avoid aggravating the congestion degree of the communication link of the inclined elevator to the main gateway; indicates the preset delay threshold; indicates the third characteristic value of the communication link of the inclined elevator to the main gateway in the previous evaluation period.

[0090] In the embodiment, the value of the preset delay threshold is 10 ms, and the value of the preset delay threshold is preset by human, and the implementer can limit it according to the actual situation, and the application does not make special limitation.

[0091] For each link in the current evaluation period, except for the communication link of the inclined elevator to the main gateway in the previous evaluation period, the third characteristic value of each link in the current evaluation period is taken as the link metric result of each link in the current evaluation period.

[0092] The sending end of the data packet is identified through the IP protocol.

[0093] For the communication link of the inclined elevator to the main gateway in the previous evaluation period, when the sending end of the data packet is the inclined elevator, the metric value of the communication link of the inclined elevator to the main gateway in the current evaluation period is taken as the link metric result of the communication link of the inclined elevator to the main gateway in the previous evaluation period in the current evaluation period.

[0094] When the sending end of the data packet is a mobile terminal other than the inclined elevator, the third characteristic value of the communication link between the inclined elevator and the main gateway in the current evaluation period is taken as the link metric result of the communication link between the inclined elevator and the main gateway in the previous evaluation period in the current evaluation period.

[0095] Further, for the communication link between the inclined elevator and the main gateway, the inclined elevator only performs network switching when traveling to the midpoint of the track section. By setting a fixed switching node at the running track of the inclined elevator, the switching process of the wireless communication network is optimized according to the signal strength distribution and the communication load change, and the stability and reliability of the communication switching are improved.

[0096] Based on the same inventive concept as the above method, the embodiments of the present application also provide an inclined elevator safety wireless communication system based on Internet technology, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, wherein the processor implements the steps of any one of the above methods of the inclined elevator safety wireless communication method based on Internet technology.

[0097] In summary, by presetting an evaluation period, the present application can periodically monitor the network state and timely find potential problems; by calculating the first characteristic value based on the signal strength of the first wireless router in the mobile terminal and the number of connected mobile terminals, the communication load and the reliability of signal transmission of the link can be reflected; by calculating the second characteristic value, the actual communication load and the potential communication load of the link are considered, and the change trend of the communication load of the link can be accurately reflected; by comprehensively considering the first characteristic value, the second characteristic value, the total amount of throughput, and the average total amount of queuing delay of data packets, the communication state of the link can be quantified comprehensively, which is beneficial to preferentially selecting a link with a less unsaturated communication state when selecting a route, so as to achieve load balancing and avoid network congestion.

[0098] Further, by monitoring the average queuing delay of the main link, it can be determined whether the main link is congested, and if the main link is congested, the link metric result of the main link is adjusted to avoid further aggravating the congestion of the main link; by the link metric result of each link, load distribution and dynamic route selection are performed, on the one hand, under the condition that the network is relatively stable, network fluctuations and network congestion problems caused by unfair route selection can be avoided; on the other hand, when the network is congested, higher priority transmission guarantee can be provided for the safety wireless communication of the inclined elevator, thereby ensuring the real-time performance of the safety monitoring of the inclined elevator.

[0099] The computer program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other processing devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other processing devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions / acts specified in the flow diagrams and / or block diagrams.

[0100] It is apparent that a person skilled in the art can make a variety of modifications to the application described above without departing from the spirit and scope of the application, which are defined by the appended claims. Therefore, the embodiments described above are considered to be illustrative and not restrictive in nature.

Claims

1. A safety wireless communication method for an inclined elevator based on Internet technology, characterized by, The method comprises the following steps: Assembling a WIFI communication network in the area where the inclined elevator is located and presetting an evaluation period of each link in the WIFI communication network, referred to as a period; Obtaining a first characteristic value of each link through the signal strength of the transmission signal of the first wireless router in each link at the mobile terminal and the number of mobile terminals connected by the first wireless router in each link; Obtaining a second characteristic value of each link through the number of mobile terminals connected by each wireless router in each link, in combination with the growth of the number of mobile terminals connected by each wireless router in each period and a preset number of periods before each period and the throughput; Obtaining a third characteristic value of each link through the first characteristic value and the second characteristic value and the total amount of the throughput of all routers in each link and the total amount of the average queuing delay of data packets; Regarding the communication link between the inclined elevator and the main gateway in the WIFI communication network in each period as each main link, measuring whether each main link is congested through the average queuing delay of data packets of the wireless router in each main link; if the main link is not congested in the previous period, taking the third characteristic value of each link in the current period as the link metric result of each link in the current period; otherwise, obtaining a metric value of the main link in the current period through the average level of the average queuing delay of data packets of all wireless routers in the main link in the previous period, the difference amount compared with the preset delay threshold and the third characteristic value of the main link in the previous period; obtaining the link metric result of each link in the current period through the third characteristic value of each link in the current period and the metric value; Performing route selection according to the OSPF protocol through the link metric result; The process of obtaining the metric value is as follows: Obtaining a calculation result of the ratio of the difference amount to the preset delay threshold; taking the calculation result of the ratio as the exponent of an exponential function with a natural constant as the base to obtain an exponential function mapping result of the ratio; The metric value is the product of the exponential function mapping result and the third characteristic value of the main link in the previous period; The process of obtaining the link metric result of each link in the current period through the third characteristic value of each link in the current period and the metric value comprises: For each link in the current period except the main link in the previous period, taking the third characteristic value of each link in the current period as the link metric result of each link in the current period; For the main link in the previous period in the current period, identifying the sending end of data packets through the IP protocol; when the sending end of data packets is the inclined elevator, taking the metric value as the link metric result of the main link in the previous period in the current period; When the sending end of data packets is a mobile terminal other than the inclined elevator, taking the third characteristic value of the main link in the previous period in the current period as the link metric result of the main link in the previous period in the current period.

2. The Internet technology-based inclined elevator safety wireless communication method according to claim 1, characterized by, The first characteristic value is a normalized value of the ratio of the number of mobile terminals connected by the first wireless router to the signal strength.

3. The Internet technology-based inclined elevator safety wireless communication method according to claim 1, characterized by, The process of obtaining the second characteristic value is as follows: The previous continuous preset number of periods adjacent to each period and each period are taken as each reference evaluation period of each period; the throughputs of each wireless router in each link in all reference evaluation periods of each period are arranged in time sequence to form a throughput sequence of each wireless router in each link in each period; a slope of a fitting straight line of each throughput sequence is obtained; The number of connected mobile terminals of each wireless router in each link in the first reference evaluation period of each period is obtained, and a difference value of the number of connected mobile terminals in the first reference evaluation period compared with the number of connected mobile terminals in the last reference evaluation period is obtained. The second characteristic value can be further obtained by the slope, the difference value, and the number.

4. The Internet technology-based inclined elevator safety wireless communication method according to claim 3, characterized by, The calculation method of the second characteristic value is: A ratio of the difference value and the number is calculated, and the reciprocal of the ratio and the slope are taken as exponents of an exponential function with a preset number greater than 1 as a base number to obtain an inverse proportional mapping result of the ratio and a direct proportional mapping result of the slope; The product of the inverse proportional mapping result and the direct proportional mapping result is calculated; The second characteristic value is the average value of the product of all wireless routers in the link. 5.The Internet technology-based inclined elevator safety wireless communication method according to claim 1, wherein, The acquisition process of the third characteristic value is: The sum value of the throughputs of all routers in the link is calculated; The cumulative value of the average queuing delay of data packets of all routers in the link is calculated; The third characteristic value is positively correlated with the first characteristic value, the second characteristic value, the sum value, and the cumulative value, respectively. 6.The Internet technology-based inclined elevator safety wireless communication method according to claim 5, wherein, The calculation method of the third characteristic value is: The normalized value of the sum value and the product value of the first characteristic value, the second characteristic value, and the third characteristic value are calculated; The normalized result of the reciprocal of the cumulative value is calculated; The third characteristic value is the ratio of the product value and the normalized result. 7.The Internet technology-based inclined elevator safety wireless communication method according to claim 1, wherein, The method for measuring whether the main link is congested is: The average value of the average queuing delay of data packets of all wireless routers in the main link is calculated, and if the average value is less than or equal to a preset delay threshold, it is determined that the main link is not congested, otherwise, it is determined that the main link is congested.

8. An inclined elevator safety wireless communication system based on Internet technology, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, The processor executes the computer program to realize the steps of the oblique elevator safety wireless communication method based on internet technology according to any one of claims 1-7.

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