WO2014040398A1 - 一种基于多接入点的tdma接入方法及装置 - Google Patents

一种基于多接入点的tdma接入方法及装置 Download PDF

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Publication number
WO2014040398A1
WO2014040398A1 PCT/CN2013/070326 CN2013070326W WO2014040398A1 WO 2014040398 A1 WO2014040398 A1 WO 2014040398A1 CN 2013070326 W CN2013070326 W CN 2013070326W WO 2014040398 A1 WO2014040398 A1 WO 2014040398A1
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Prior art keywords
aps
sta
access
module
tdma
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English (en)
French (fr)
Inventor
梁炜
刘帅
张晓玲
杨雨沱
于海斌
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Shenyang Institute of Automation of CAS
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Shenyang Institute of Automation of CAS
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Priority to US14/427,210 priority Critical patent/US9780898B2/en
Priority to EP13837737.9A priority patent/EP2897399B1/en
Publication of WO2014040398A1 publication Critical patent/WO2014040398A1/zh
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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J3/00—Time-division multiplex systems
    • H04J3/16—Time-division multiplex systems in which the time allocation to individual channels within a transmission cycle is variable, e.g. to accommodate varying complexity of signals, to vary number of channels transmitted
    • H04J3/1694—Allocation of channels in TDM/TDMA networks, e.g. distributed multiplexers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W40/00—Communication routing or communication path finding
    • H04W40/24—Connectivity information management, e.g. connectivity discovery or connectivity update
    • H04W40/244—Connectivity information management, e.g. connectivity discovery or connectivity update using a network of reference devices, e.g. beaconing
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
    • H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
    • H04B7/2643—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA]
    • H04B7/2656—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using time-division multiple access [TDMA] for structure of frame, burst
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0053—Allocation of signalling, i.e. of overhead other than pilot signals
    • H04L5/0055—Physical resource allocation for ACK/NACK
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W16/00—Network planning, e.g. coverage or traffic planning tools; Network deployment, e.g. resource partitioning or cells structures
    • H04W16/18—Network planning tools
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W48/00—Access restriction; Network selection; Access point selection
    • H04W48/08—Access restriction or access information delivery, e.g. discovery data delivery
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/04—Wireless resource allocation
    • H04W72/044—Wireless resource allocation based on the type of the allocated resource
    • H04W72/0446—Resources in time domain, e.g. slots or frames

Definitions

  • the present invention relates to industrial wireless network technologies, and more particularly to a TDMA access method and apparatus based on multiple access points. Background technique
  • Industrial wireless network technology is another hotspot technology in the field of industrial measurement and control after fieldbus. It is a revolutionary technology to reduce the cost of industrial measurement and control systems and improve the application range. It is also a new growth point for industrial automation products in the next few years. Industrial wireless network technology is suitable for harsh industrial field environment, with strong anti-interference ability, low energy consumption, real-time communication and other technical features. It is the function expansion and technological innovation of the existing wireless technology in the industrial application direction, and finally translated into New wireless technology standards. At present, industrial wireless network technology is gradually applied to the field of high-speed factory automation, and has become another focus of international wireless network technology competition after industrial wireless network technology for process automation.
  • Industrial wireless network for factory automation that is, factory automation wireless network, not only has the advantages of low cost, easy installation and easy maintenance of industrial wireless network, but also avoids cable aging, cable pollution, slip ring caused by mobile equipment. Power contact is easy to fail and other issues.
  • factory automation wireless networks face more demanding requirements: (1) large network scale, requiring the number of nodes supporting 100 to 1000 points; (2) high communication rate, the transmission rate requires the order of Mbit/s; (3) High reliability, end-to-end transmission success rate requires lOe-9; (4) High real-time performance, end-to-end communication delay requirement is less than 10ms.
  • time division multiple access TDMA, Time Division
  • the Multiple Access mechanism is an ideal access mechanism for the Medium Access Control (MAC) layer of industrial wireless networks.
  • MAC Medium Access Control
  • the reasons are: First, industrial wireless networks have deterministic requirements for performance; secondly, due to the limitations of industrial application environments, the topology of most existing networks is relatively fixed and often hierarchical; in addition, data in industrial sites Most have periodic features.
  • the current factory automation wireless network mostly adopts a single access point (AP, Access Point) star network topology, and a single AP becomes the bottleneck of the entire network.
  • AP access point
  • Access Point Access Point
  • the network collapses; in addition, there are many mobile devices such as robots, track-mounting devices, and automated guided vehicles (AGVs) in the factory environment, which require industrial wireless monitoring Network nodes have mobility capabilities.
  • the network node may move to an area that cannot communicate with a single AP, causing packet transmission failure and affecting the reliability of the industrial wireless network.
  • An intuitive and effective way to solve the above problems is to have multiple APs in the network, and other sites can communicate with multiple APs. Summary of the invention
  • the TDMA method cannot simultaneously meet the current situation of real industrial applications and the reliability requirements.
  • the present invention introduces multiple access points, and proposes a TDMA access method and apparatus based on multiple access points.
  • a TDMA access method based on multiple access points including
  • the multi-AP access device is used as a time source of the entire network, and the STA performs time synchronization by using a beacon frame broadcast by the multi-AP access device;
  • the multi-AP access device including n APs is divided into k groups, k is a natural number, and l k n;
  • Any group 3 ⁇ 4 reserves a time slot from the i-th sub-superframe in its corresponding i-th super-frame, and the number of reserved slots is equal to the number of APs in the group j;
  • the beacon frame is a broadcast frame sent by ⁇ , including network number, time slot stamp, and network resource management.
  • the grouping principle of dividing a multi-access device comprising n ⁇ into k groups is:
  • the network management module After the multi-AP access device receives the data packet of the STA, the network management module returns an ACK to the STA: if only one AP receives the data packet of the STA, the AP directly replies to the ACK; if multiple APs receive the STA For each data packet, each AP replies with an ACK according to the packet reception success rate and the received signal strength RSSI.
  • the principle that the respective APs reply ACK according to the packet receiving success rate and the received signal strength RSSI is: when multiple APs receive the STA data packet, search the communication link quality mapping table, and find the maximum success rate of the packet receiving success in the corresponding STA.
  • the AP sends an ACK in the corresponding time slot by the AP.
  • the APs are further searched for the AP with the largest RSSI value, and the AP sends an ACK in the corresponding time slot. Multiple APs with the same success rate and equal RSSI values are randomly selected to ACK.
  • the communication link quality mapping table is a mapping table maintained in the gateway for the quality of each STA and all AP communication links in the network, including the packet reception success rate and the RSSI indicator value, as the communication process is continuously updated.
  • a TDMA access device based on multiple access points, including a station STA, an access point AP, a gateway, and a controller, wherein the STA connects to the field device at the industrial site, is responsible for collecting field data and controlling the production process, and the STA is connected with the multi-AP.
  • Multiple access points APs in the device are wirelessly connected; the plurality of access points AP are wiredly connected to one of the multiple AP access devices; the multi-AP access device is used to collect the field devices of the STA
  • the sensor data is forwarded to the controller, and the control information of the controller is forwarded to the actuator on the field device.
  • the plurality of APs share an address and work in parallel.
  • the multi-AP access device includes: a TDMA module, a user datagram protocol communication module, a filter packet module, a buffer management module, and a network management module; wherein, the user datagram protocol communication module adopts UDP communication The protocol is used for forwarding data packets from multiple APs; the filter packet module is connected to the user datagram protocol communication module, and is used for filtering redundant duplicate packets; the buffer management module is connected to the user datagram protocol communication module and the filter packet module, The management access buffer area; the network management module is connected to the buffer management module for transmitting the data packet to the gateway; the TDMA module is connected to the user datagram protocol communication module and the network management module for organizing TDMA superframe communication, including ACK reply Submodule.
  • the multi-access point-based TDMA access method and device proposed by the present invention are proposed under the premise of fully considering the transmission characteristics of the wireless network and the characteristics of the industrial automation application, and adopting multiple access points can greatly reduce the loss. Packet rate, improve system reliability, reduce the number of retransmissions, improve resource utilization, increase network capacity, and improve system effective throughput.
  • the specific performance is as follows:
  • the method of the present invention adopts multiple access point redundant communication mode, and sends data to a certain station (STA, STAtion), even if some APs do not receive data due to electromagnetic interference or occlusion of the industrial environment, as long as at least one AP is guaranteed to receive It is enough to get the data, thus improving the reliability of the system;
  • the STA can receive time synchronization of beacon frames from multiple APs in one super frame period, thereby improving time synchronization precision, thereby shortening time slots and improving resource utilization;
  • the method of the present invention selects a reliable AP reply acknowledgement message (ACK, ACKnowledgement) method corresponding to the STA according to the quality of the communication link, and avoids the reply of the access device in the case of multiple APs under the premise of ensuring high reliability of the ACK reply.
  • ACK conflict reduce the number of retransmissions, and improve resource utilization;
  • the multi-AP access device proposed by the present invention is based on a modular design method, and is designed to receive duplicate packets with the same serial number and industrial different types of data for multiple APs, and specially designed a filter packet module and a buffer management module. It reduces the difficulty of maintenance and management of the entire device, and has the advantages of flexibility, low energy consumption and easy implementation.
  • Figure 1 is a schematic diagram of a star topology of a typical industrial wireless network
  • 2 is a schematic diagram of a TDMA superframe
  • FIG. 3 is a schematic structural diagram of a multi-AP access device
  • Figure 4 is a flow chart of data reception of the UDP communication module
  • Figure 5 shows the working flow chart of the filter package module. detailed description
  • the invention provides a TDMA access method and device based on multiple access points, which is based on a star-structured factory automation wireless network built by multiple STA devices and multiple AP access devices, as shown in FIG. 1 Shown.
  • STA connects sensors, brakes, actuators, etc. in the industrial field, and is responsible for collecting field data and controlling the production process.
  • the multi-AP access device is composed of multiple APs and one gateway, and is responsible for data interaction between the field device and the controller. Specifically, the sensor data on the field device is forwarded to the controller or the control information of the controller is forwarded to the actuator on the field device.
  • a wired connection is used between the multiple AP access device and the gateway, and multiple APs in the multiple AP access device share an address and work in parallel.
  • a TDMA superframe is a periodically repeated set of time slots, as shown in Figure 2 (a) for a single AP superframe. Intention. Assuming that the length of the superframe is m, the AP broadcasts the beacon frame by using the first slot of the superframe. After passing m slots, the AP broadcasts the beacon frame again to indicate the start of the next superframe.
  • a beacon frame is a broadcast frame sent by an AP, and contains information such as network number, timestamp, and network resource management.
  • the network requires strict time synchronization.
  • the multiple AP access devices in the network serve as the time source of the entire network, and the STAs in the network use the beacon frames broadcast by the multiple AP access devices for time synchronization.
  • the beacon frame transmission process adopts a packet management mode.
  • the AP grouping principle includes:
  • the TDMA communication process corresponding to the AP after the packet specifically includes the following steps:
  • a superframe of length m (satisfying m»n) is divided into k subsuperframes.
  • the i-th sub-superframe corresponds to the group 3 ⁇ 4 (l ⁇ i ⁇ k);
  • Any group Bi (l ⁇ i ⁇ k) reserves time slots from the i-th sub-superframe in its corresponding i-th sub-superframe, and the number of reserved slots is equal to the group 3 ⁇ 4 (l ⁇ i ⁇ k) the number of APs within;
  • the broadcast of other beacon frames is similar, and the final result is shown in Figure 2 (b).
  • the method of group management is adopted for the broadcast of the AP beacon frame, that is, the multi-AP technology is adopted.
  • the time synchronization can be completed, and the STA may be Multiple time synchronization in the superframe period improves the time synchronization accuracy; in addition, the method is simple and flexible, which reduces the difficulty of maintenance and management.
  • a plurality of APs in the multiple AP access device share an address and work in parallel.
  • the specific mechanism is that when the STA sends a data packet, multiple APs simultaneously receive.
  • the gateway filters out the duplicate packet by means of a sequence number or the like.
  • the method for the multiple AP access device to reply the ACK to the STA is as follows:
  • each AP replies to the ACK according to the packet reception success rate and Received Signal Strength Indication (RSSI).
  • RSSI Received Signal Strength Indication
  • the specific principles include: When multiple APs receive STA data. In the case of a packet, the communication link quality mapping table is searched, and the AP with the highest packet reception success rate in the corresponding STA is found, and the AP sends an ACK in the corresponding time slot;
  • the AP sends an ACK in the corresponding time slot by the AP;
  • the communication link quality mapping table refers to a mapping table maintained in the gateway for maintaining the quality of each STA and all AP communication links in the network in order to support an ACK reply mechanism based on the quality of the communication link.
  • the communication link quality mainly includes the packet reception success rate and the RSSI indicator value, and the communication link quality mapping table is continuously updated along with the communication process.
  • the present invention provides a multi-AP access device.
  • the multi-AP access device includes five modules: a TDMA module, and a User Datagram Protocol (UDP) communication module. , filter package module, cache management module and network management module.
  • the TDMA module is responsible for organizing TDMA superframe communication;
  • the UDP communication module uses UDP communication protocol for forwarding data packets from multiple APs;
  • the filter packet module is used for filtering redundant duplicate packets;
  • the buffer management module is used for managing storage.
  • the cache area the network management module is the core of the entire device, responsible for managing and maintaining the entire network, including the ACK reply sub-module.
  • each module of the multiple AP access device The functions and processes of each module of the multiple AP access device are as follows:
  • the TDMA module contains the time source of the entire system, which is used to divide the time slot in the time domain.
  • the TDMA module queries the link table provided by the network management module, and judges here. Whether the time slot has communication services. If there is no communication service, it will not operate and enter the sleep state. If there is a communication service, it is further determined whether it is a transmission time slot or a reception time slot: if it is a reception time slot, a plurality of APs are set to a reception state; if it is a transmission time slot, the TDMA module calls a UDP communication module.
  • the UDP module first retrieves the data packet in the transmission buffer through the interface provided by the buffer management module, and then forwards it to the corresponding AP through the UDP communication protocol for transmission.
  • the principle of replying with the ACK is the same as the principle.
  • multiple APs in the multiple AP access device may simultaneously receive data packets coming from the same STA and forward them to the UDP communication module through the UDP communication protocol.
  • the UDP communication module may include multiple duplicate packets, and the UDP communication module calls the filter packet module to filter the redundant duplicate packets, and puts the filtered data packets into the receiving buffer through the interface provided by the buffer management module.
  • the management module obtains the data packet through the interface provided by the buffer management module, and performs corresponding processing.
  • the UDP communication module has the characteristics of no need to maintain connection and suitable for short control information transmission, and can meet the high real-time and bandwidth requirements of industrial wireless communication.
  • the data receiving process of the UDP communication module is shown in Figure 4.
  • the initialization part includes UDP module initialization, buffer area module initialization, and filter packet module initialization.
  • the UDP communication module queries the UDP data of the AP and returns the data length. If the data length is greater than 0, the AP has forwarded the data to the UDP communication module through the UDP communication protocol, and calls the function in the filter packet module to process the data; Go to the next AP for processing. In this way, the UDP data of each AP is polled cyclically.
  • Filter package module The filter package module internally maintains a sliding window for recording the serial number of the most recently received UDP packets, and is continuously updated as the number of data packets in the receive buffer increases.
  • Filter pack module input It is the packet first address, the packet length, and the serial number of the packet.
  • the program flow chart of the filter packet module is as shown in FIG. 5, firstly determining whether there is a serial number of the data packet in the sliding window, if it exists, repeating the packet, discarding the data packet; if not, further determining the receiving buffer area If it is full, discard this packet, otherwise add this packet to the receive buffer and then update the sliding window.
  • the cache management module uses a circular queue implemented by an array to construct and maintain a transmission buffer and a receive buffer. It does not need to frequently call the memory allocation function, and has fast running speed, flexible flexibility, and access efficiency. Higher characteristics; At the same time, for different types of frames in actual industrial communication (generally divided into data frames, command frames, Beacon frames, ACK frames), the length information is first recorded in the buffer area of each frame. Its access program can automatically handle different types of frames correctly, ensuring the consistency of frame access of different lengths.
  • Network management module The network management module manages and maintains the network according to the content of the received data packet, and replies with an ACK.

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Description

一种基于多接入点的 TDMA接入方法及装置 技术领域
本发明涉及工业无线网络技术， 具体地说是一种基于多接入点的 TDMA接入方 法及装置。 背景技术
工业无线网络技术是继现场总线之后， 工业测控领域的又一个热点技术， 是降低 工业测控系统成本、提高应用范围的革命性技术， 也是未来几年工业自动化产品新的 增长点。工业无线网络技术适用于恶劣的工业现场环境，具有抗干扰能力强、能耗低、 实时通信等技术特征， 是对现有无线技术在工业应用方向上的功能扩展和技术创新， 并最终转化为新的无线技术标准。 目前， 工业无线网络技术逐渐应用于高速的工厂自 动化领域，成为继面向过程自动化的工业无线网络技术之后， 国际上无线网络技术竞 争的又一焦点。 面向工厂自动化的工业无线网络， 即工厂自动化无线网络， 不仅具有 工业无线网络低成本、 易安装、 易维护的优势， 而且能够避免工厂设备因移动导致的 线缆易老化、 线缆污染、 滑环电力接触易失败等问题。 然而， 工厂自动化无线网络面 临着更加苛刻的需求： （1 )大网络规模， 要求支持百点至千点的节点数量； （2)高通 信速率，传输速率要求 Mbit/s的量级；（3 )高可靠性，端到端的传输成功率要求 lOe-9; (4) 高实时性， 端到端的通信延迟要求低于 10ms。
基于工厂自动化无线网络的上述需求， 时分多路访问 （TDMA, Time Division
Multiple Access ) 机制是工业无线网络较为理想的机制访问控制 （MAC , Medium Access Control) 层的接入机制。 究其原因在于： 首先， 工业无线网络对性能具有确 定性要求； 其次， 受工业应用环境的限制， 现有大多数网络的拓扑结构相对固定且常 为层次性结构； 此外， 工业现场中的数据大多具有周期性特征。
然而， 采用 TDMA机制的工厂自动化无线网络中仍存在下述问题： （1 ) 由于无 线介质的开放性以及工业电磁干扰环境的特殊性，数据包传输有较大的不可控、不确 定性，甚至多次重传后也难以达到端到端的可靠性要求，特别是工厂自动化应用；（2) 预先分配固定数目的重传时隙实现高可靠性是工业无线网络最为常用的方法，然而实 际中多数重传时隙都得不到利用， 导致资源利用率低， 从而使得工业无线网络难以容 纳大规模的节点。
目前的工厂自动化无线网络多采用单接入点 （AP， Access Point) 的星型网络拓 扑， 是的单个 AP成为整个网络的瓶颈。一旦单个 AP出现故障， 则网络崩溃； 此外， 此外， 工厂环境中有许多诸如机器人、轨道挂载设备、无人搬运车（AGV， Automated Guided Vehicle)等移动设备， 从而要求对其监控的工业无线网络节点具有移动能力。 在这种应用场合下， 网络节点可能移动到与单个 AP无法通信的区域， 导致报文传输 失败， 影响工业无线网络的可靠性。解决上述问题的一种直观而有效的方法是网络中 布设多个 AP， 其他站点可以与多个 AP进行通信。 发明内容
针对现有静态网络中 AP故障导致网络崩溃的问题， 以及现有针对工业无线网络 的 TDMA方法无法同时满足实际工业应用的实时性和可靠性需求的现状， 本发明引 入多个接入点， 提出一种基于多接入点的 TDMA接入方法及装置。
本发明为实现上述目的所采用的技术方案是： 一种基于多接入点的 TDMA接入 方法， 包括
令多 AP接入装置作为整个网络的时间源， STA利用多 AP接入装置广播的信标 帧进行时间同步；
将包含 n个 AP的多 AP接入装置分成 k组， k 为自然数， 且 l k n;
根据任意组 = {APn, APl2, ... ΑΡ^内 AP的数量 j，将长度为 m的超帧划分成 k 个子超帧， 其中， 第 i个子超帧对应组 B1;
任意组 ¾在其对应的第 i个子超帧内， 从第 i个子超帧开始预留时隙， 预留时隙 的数量等于组 内 AP的数量 j;
对于任意组 ¾ ( l i k) 内的 ΑΡ， 如果 ASN % m = (m/k)*(i - l) + j为真， 则 ΑΡ 在时隙 ASN内广播信标帧， 否则不作任何响应， 其中 ASN为当前的绝对时隙号 并从 1开始计数。
所述信标帧是由 ΑΡ发出的广播帧， 包括网络编号、 时隙戳和网络资源管理。 所述将包含 η个 ΑΡ的多 ΑΡ接入装置分成 k组的分组原则为：
( 1 ) 组内各个 AP传输范围的重叠部分最小；
(2) 组内所有 AP的传输范围的并集能够覆盖整个网络。
所述任意组 = {APn, APl2, ... AP AP的数量 的计算方法为：如果 n % k==0 , 则 否则， l i k-l时，
Figure imgf000004_0001
当多 AP接入装置收到 STA的数据包后，网络管理模块给 STA回复 ACK的方法 为： 如果只有一个 AP收到 STA的数据包， 则该 AP直接回复 ACK; 如果多个 AP收 到 STA的数据包， 则各个 AP根据包接收成功率以及接受信号强度 RSSI回复 ACK。
所述各个 AP根据包接收成功率以及接受信号强度 RSSI回复 ACK的原则为：当 多个 AP收到 STA的数据包时， 搜索通信链路质量映射表， 找到对应 STA中包接收 成功率最大的 AP， 由该 AP在对应的时隙发送 ACK; 对于包接收成功率相同的多个 AP,则在这些 AP中进一步搜索 RSSI值最大的 AP，由该 AP在对应的时隙发送 ACK; 对于包接收成功率相同且 RSSI值相等的多个 AP， 随机选择一个 AP回复 ACK。
所述通信链路质量映射表是网关中维护的一个关于网络中每个 STA与所有 AP 通信链路质量的映射表， 包括包接收成功率以及 RSSI指标值， 随着通信过程不断更 新。
一种基于多接入点的 TDMA接入装置， 包括站点 STA、接入点 AP、 网关和控制 器， 其中 STA在工业现场连接现场设备， 负责采集现场数据以及控制生产过程， STA 与多 AP接入装置中的多个接入点 AP无线连接； 所述多个接入点 AP与多 AP接入 装置中的一个网关有线连接;所述多 AP接入装置用于将 STA采集的现场设备的传感 器数据转发到控制器， 将控制器的控制信息转发给现场设备上的执行器。
所述多个 AP共用一个地址， 并行工作。
所述多 AP接入装置包括： TDMA模块、 用户数据报协议通信模块、 滤包模块、 缓存区管理模块以及网络管理模块； 其中， 用户数据报协议通信模块采用 UDP通信 协议， 用于转发来自于多个 AP的数据包； 滤包模块连接用户数据报协议通信模块， 用于过滤多余的重复包； 缓存区管理模块连接用户数据报协议通信模块和滤包模块， 用于管理存取缓存区；网络管理模块连接缓存区管理模块，用于将数据包发送给网关; TDMA模块连接用户数据报协议通信模块和网络管理模块， 用于组织 TDMA超帧通 信， 包括 ACK回复子模块。
本发明具有以下优点：
本发明提出的一种基于多接入点的 TDMA接入方法及装置， 是在充分考虑无线 网络的传输特点以及工业自动化应用特点的前提下提出的，采用多接入点， 可以极大 地减少丢包率， 提高系统可靠性， 减少重传次数， 提高资源利用率， 增加网络容量， 提高系统有效吞吐量， 具体表现在：
1. 本发明方法采用多接入点冗余通信方式， 对于某个站点 （STA， STAtion) 发 送数据， 即使由于工业环境电磁干扰或遮挡导致部分 AP没有接收到数据， 但只要保 证至少一个 AP接收到数据即可， 因此提高了系统的可靠性；
2. 本发明方法中， STA在一个超帧周期内， 可以接收来自多个 AP的信标帧进 行时间同步， 提高了时间同步精度， 进而可缩短时隙， 提高了资源利用率；
3. 本发明方法设计根据通信链路质量选择 STA对应的可靠 AP 回复确认消息 (ACK, ACKnowledgement) 方法， 在保证了 ACK回复的高可靠性的前提下， 避免 了多 AP情况下接入设备回复 ACK的冲突， 减少重传次数， 提高资源利用率；
4. 本发明提出的多 AP接入装置， 基于模块化设计方法， 针对多 AP收到具有 相同序列号的重复包与工业不同类型数据等情况特点，特别设计了滤包模块和缓存区 管理模块，降低了整个装置维护和管理的难度，具有灵活、低能耗和易于实现等优点。 附图说明
图 1 为一个典型的工业无线网络的星型拓扑结构示意图；
图 2为 TDMA超帧示意图；
图 3为多 AP接入装置的结构示意图；
图 4为 UDP通信模块的数据接收流程图；
图 5为滤包模块的工作流程图。 具体实施方式
下面结合附图及实施例对本发明做进一步的详细说明。
本发明提出的一种基于多接入点的 TDMA接入方法及装置， 建立在由多个 STA 设备和多 AP接入装置搭建成的星型结构的工厂自动化无线网络的基础上， 如图 1所 示。 其中， STA在工业现场连接传感器、 制动器、 执行器等的设备， 负责采集现场 数据以及控制生产过程； 多 AP接入装置由多个 AP和一个网关组成， 负责现场设备 与控制器间的数据交互， 具体说， 是将现场设备上的传感器数据转发到控制器或者将 控制器的控制信息转发给现场设备上的执行器。多 AP接入装置和网关之间采用有线 连接， 多 AP接入装置中的多个 AP共用一个地址， 并行工作。
网络组建后， 多 AP接入装置与 STA之间的通信采用基于信标的 TDMA超帧进 行组织。 TDMA超帧是周期性重复的时隙集合， 如图 2 (a) 所示为单 AP超帧的示 意图。假设超帧的长度为 m， AP利用超帧的第一时隙广播信标帧，经过 m个时隙后， AP再次广播信标帧表示下一个超帧的开始。 信标帧是由 AP发出的广播帧， 包含网 络编号、 时间戳、 网络资源管理等组织通信的信息。
在 TDMA通信的整个过程中， 网络要求进行严格的时间同步。 网络中的多 AP 接入装置作为整个网络的时间源， 网络中的 STA利用多 AP接入装置广播的信标帧 进行时间同步。
对于包含 n个 AP的多 AP接入装置， 信标帧的发送过程采用分组管理模式。 将 n个 AP分成 k组， k 为自然数， 且 l k n。 其中， 对于任意组 ¾ (l^i^k) ， AP的分组原则包括：
(1) 组内各个 AP传输范围的重叠部分最小；
(2) 组内所有 AP的传输范围的并集能够覆盖整个网络。
将任意组¾ (l^i^k) 内的 AP标记为 {APu，APl2， … APy}, 其中， j的数 值计算如下：
(3) 如果 n%k==0， 贝 ljj=n/k;
(4) 否贝 lj， l i k-l时， j= ， i=k时， j=+ (n%k) 。
分组后的 AP对应的 TDMA通信过程具体包括以下步骤：
(1)根据任意组 ¾ (l i k)内 AP的数量， 将长度为 m的超帧（满足 m»n) 划分成 k个子超帧。 其中， 第 i个子超帧对应组¾ (l^i^k) ；
(2) 任意组 Bi (l^i^k) 在其对应的第 i个子超帧内， 从第 i个子超帧开始预 留时隙， 预留时隙的数量等于组¾ (l^i^k) 内 AP的数量；
(3)假设当前的绝对时隙号为 ASN (从 1开始计数），对于任意组 (l i k) 内的 ΑΡ， 如果 ASN % m = (m/k)*(i - l)+j为真， 则 ΑΡ 在时隙 ASN内广播信标帧， 否则不作任何响应。
下面结合图 2 (b) 具体说明多 AP接入装置分组广播信标帧的过程。 假设多 AP 接入装置包含 6个 AP (n = 6) ， 分别表示为 AP„、 AP12、 AP13、 AP21、 AP22、 AP23， 分为两组 （k = 2) ， 分组结果为 Bi={ AP„， AP12， AP13}， B2={AP21， AP22， AP23}， 则 Bl组和 B2组内均包含 3个 AP。 假设超帧长度为 16 (m= 16) ， 并将该超帧划分 为两个子超帧， 分别对应 B1组和 B2组； 预留两个子超帧的前三个时隙， 分别用于 Bj组和 B2组内 AP广播信标帧。 对于 ASN = 2， 贝 Ij i = 1， j = 2时， 满足公式 ASN % m = (m/k)*(i- l)+j为真， 即此时 AP12发送信标帧。 其他信标帧的广播情况类似， 最 后的结果如图 2 (b) 所示。
对 AP信标帧的广播采取分组管理的方法， 即采用多 AP技术， 对于每个 STA， 只要保证在超帧周期内接收任意一个 AP的信标帧， 即可完成时间同步， 且 STA可 能在超帧周期内进行多次时间同步， 提高了时间同步精度； 此外， 该方法简单灵活， 降低了维护和管理的难度。
所述多 AP接入装置中的多个 AP共用一个地址， 并行工作， 其具体机制在于当 STA发送数据包的时候，多个 AP同时接收。对于多个 AP收到来自 STA的同一个数 据包的情况， 网关通过序列号等方法过滤掉重复包。
多 AP接入装置给 STA回复 ACK的方法如下：
(1) 如果只有一个 AP收到 STA的数据包， 则该 AP直接回复 ACK; (2) 如果多个 AP收到 STA的数据包， 则各个 AP根据包接收成功率以及接受 信号强度 （RSSI， Received Signal Strength Indication) 回复 ACK， 具体原则包括： 当多个 AP收到 STA的数据包时， 搜索通信链路质量映射表， 找到对应 STA中 包接收成功率最大的 AP， 由该 AP在对应的时隙发送 ACK;
对于包接收成功率相同的多个 AP， 则在这些 AP中进一步搜索 RSSI值最大的
AP， 由该 AP在对应的时隙发送 ACK;
对于包接收成功率相同且 RSSI值相等的多个 AP， 随机选择一个 AP回复 ACK。 所述通信链路质量映射表， 是指为支持基于通信链路质量的 ACK回复机制， 网 关中维护的一个关于网络中每个 STA与所有 AP通信链路质量的映射表。 其中， 通 信链路质量主要包括包接收成功率以及 RSSI指标值， 通信链路质量映射表随着通信 过程不断更新。
为实现上述方法， 本发明提出了一种多 AP接入装置， 如图 3所示， 该多 AP接 入装置包括五个模块： TDMA模块、用户数据报协议（UDP， User Datagram Protocol ) 通信模块、 滤包模块、 缓存区管理模块以及网络管理模块。 其中， TDMA模块负责 组织 TDMA超帧通信； UDP通信模块采用 UDP通信协议， 用于转发来自于多个 AP 的数据包； 滤包模块用于过滤多余的重复包； 缓存区管理模块用于管理存取缓存区； 网络管理模块是整个装置的核心， 负责管理、 维护整个网络， 其中包括 ACK回复子 模块。
多 AP接入装置的各个模块的功能和流程具体如下：
( 1 ) TDMA模块： TDMA模块包含整个系统的时间源， 用于在时间域上划分时 隙， 当触发 "时隙开始"事件时， TDMA模块查询网络管理模块提供的链路表， 判 断在此时隙是否有通信业务。 如果没有通信业务， 则不动作， 进入休眠状态。 如果有 通信业务， 则进一步判断是发送时隙还是接收时隙： 如果为接收时隙， 则将多个 AP 设置为接收状态； 如果为发送时隙， TDMA模块调用 UDP通信模块。
(2) UDP通信模块： UDP模块首先通过缓存区管理模块提供的接口取出发送缓 存区中的数据包， 然后通过 UDP通信协议转发给对应的 AP进行发送， 选择原则同 回复 ACK的原则。 在接收时隙中， 多 AP接入装置中的多个 AP可能同时接收到来 自于同一个 STA的数据包， 并通过 UDP通信协议将其转发给 UDP通信模块。此时， UDP通信模块中可能包含多个重复包， UDP通信模块调用滤包模块来过滤多余的重 复包， 并通过缓存区管理模块提供的接口将过滤后的数据包放入接收缓存区， 网络管 理模块通过缓存区管理模块提供的接口获取数据包， 并做相应的处理。
UDP通信模块具有不需要保持连接、 适合较短的控制信息传输等特点， 能够满 足工业无线通信的高实时性、 带宽要求。 UDP通信模块的数据接收流程如图 4所示， 初始化部分包括 UDP模块初始化、 缓存区模块初始化以及滤包模块初始化。 UDP通 信模块查询 AP的 UDP数据并返回数据长度， 如果数据长度大于 0， 则说明 AP已 经将数据通过 UDP通信协议转发给了 UDP通信模块，并调用滤包模块中函数对数据 进行处理； 否则切换到下一个 AP进行处理。 如此往复， 循环轮询每个 AP的 UDP 数据。
( 3 )滤包模块：滤包模块内部维护一个滑动窗口，用于记录最近接收的多个 UDP 数据包的序列号， 并且随着接收缓存区中数据包的增加而不断更新。滤包模块的输入 为数据包首地址、数据包长度、数据包的序列号。滤包模块的程序流程图如图 5所示， 首先判断滑动窗口中是否有此数据包的序列号， 如果存在， 则是重复包， 丢弃此数据 包； 如果不存在， 则进一步判断接收缓存区是否已满， 若已满， 则丢弃此数据包， 否 则将此数据包加入接收缓存区， 然后更新滑动窗口。
(4) 缓存区管理模块： 缓存区管理模块采用由数组实现的环形队列， 构建和维 护发送缓存区和接收缓冲区， 不需要频繁调用内存分配函数， 具有运行速度快、变化 灵活、存取效率高等特点； 同时针对实际工业通信中不同类型帧（一般可分为数据帧、 命令帧、 Beacon帧、 ACK帧） 的长度不同这一情况， 在各个帧的缓存区， 首先记录 了其长度信息，使其存取程序能够自动正确处理不同类型的帧，保证了不同长度帧存 取的一致性。
(5 ) 网络管理模块： 网络管理模块根据接收到的数据包的内容， 对网络进行管 理和维护， 并回复 ACK。

Claims

权 利 要 求 书
1 . 一种基于多接入点的 TDMA接入方法， 其特征在于， 包括
令多 AP接入装置作为整个网络的时间源， STA利用多 AP接入装置广播的信标 帧进行时间同步；
将包含 n个 AP的多 AP接入装置分成 k组， k 为自然数， 且 l k n;
根据任意组 = {APn , APl2, . . . ΑΡ^内 AP的数量 j，将长度为 m的超帧划分成 k 个子超帧， 其中， 第 i个子超帧对应组 B1 ;
任意组 ¾在其对应的第 i个子超帧内， 从第 i个子超帧开始预留时隙， 预留时隙 的数量等于组 内 AP的数量 j;
对于任意组 ¾ ( l i k) 内的 ΑΡ， 如果 ASN % m = (m/k)*(i - l) + j为真， 则 ΑΡ 在时隙 ASN内广播信标帧， 否则不作任何响应， 其中 ASN为当前的绝对时隙号 并从 1开始计数。
2. 根据权利要求 1所述的一种基于多接入点的 TDMA接入方法， 其特征在于， 所述信标帧是由 ΑΡ发出的广播帧， 包括网络编号、 时隙戳和网络资源管理。
3 . 根据权利要求 1所述的一种基于多接入点的 TDMA接入方法， 其特征在于， 所述将包含 n个 AP的多 AP接入装置分成 k组的分组原则为：
( 1 ) 组内各个 AP传输范围的重叠部分最小；
( 2 ) 组内所有 AP的传输范围的并集能够覆盖整个网络。
4. 根据权利要求 1所述的一种基于多接入点的 TDMA接入方法， 其特征在于， 所述任意组 = {ΑΡπ, APl2, ... APy}内 AP的数量 j的计算方法为： 如果 n % k==0 , 则 否则， l i k- l时，
Figure imgf000009_0001
5 . 根据权利要求 1所述的一种基于多接入点的 TDMA接入方法， 其特征在于， 当多 AP接入装置收到 STA的数据包后， 网络管理模块给 STA回复 ACK的方法为： 如果只有一个 AP收到 STA的数据包， 则该 AP直接回复 ACK; 如果多个 AP收到 STA的数据包， 则各个 AP根据包接收成功率以及接受信号强度 RSSI回复 ACK。
6. 根据权利要求 1所述的一种基于多接入点的 TDMA接入方法， 其特征在于， 所述各个 AP根据包接收成功率以及接受信号强度 RSSI回复 ACK的原则为：当多个 AP收到 STA的数据包时， 搜索通信链路质量映射表， 找到对应 STA中包接收成功 率最大的 AP， 由该 AP在对应的时隙发送 ACK; 对于包接收成功率相同的多个 AP， 则在这些 AP中进一步搜索 RSSI值最大的 AP， 由该 AP在对应的时隙发送 ACK;对 于包接收成功率相同且 RSSI值相等的多个 AP， 随机选择一个 AP回复 ACK。
7. 根据权利要求 6所述的一种基于多接入点的 TDMA接入方法， 其特征在于， 所述通信链路质量映射表是网关中维护的一个关于网络中每个 STA与所有 AP通信链 路质量的映射表， 包括包接收成功率以及 RSSI指标值， 随着通信过程不断更新。
8. 一种实现权力要求 1 -7任一项所述方法的装置， 包括站点 STA、 接入点 AP、 网关和控制器， 其中 STA在工业现场连接现场设备， 负责采集现场数据以及控制生 产过程， 其特征在于， STA与多 AP接入装置中的多个接入点 AP无线连接； 所述多 个接入点 AP与多 AP接入装置中的一个网关有线连接； 所述多 AP接入装置用于将 STA采集的现场设备的传感器数据转发到控制器，将控制器的控制信息转发给现场设 备上的执行器。
9. 根据权利要求 8所述的装置， 其特征在于， 所述多个 AP共用一个地址， 并 行工作。
10.根据权利要求 8所述的装置，其特征在于，所述多 AP接入装置包括： TDMA 模块、 用户数据报协议通信模块、 滤包模块、 缓存区管理模块以及网络管理模块； 其 中， 用户数据报协议通信模块采用 UDP通信协议， 用于转发来自于多个 AP的数据 包； 滤包模块连接用户数据报协议通信模块， 用于过滤多余的重复包； 缓存区管理模 块连接用户数据报协议通信模块和滤包模块，用于管理存取缓存区； 网络管理模块连 接缓存区管理模块， 用于将数据包发送给网关； TDMA模块连接用户数据报协议通 信模块和网络管理模块， 用于组织 TDMA超帧通信， 包括 ACK回复子模块。
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Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10659135B2 (en) * 2014-06-16 2020-05-19 Qualcomm Incorporated Coordinated discovery of MMW connection points and UES
EP3236689B1 (en) * 2014-12-15 2019-06-19 Sony Corporation Information processing device, wireless communication device, information processing method, and program
US9648616B2 (en) 2015-01-15 2017-05-09 Nokia Solutions And Networks Oy Method and apparatus for implementing efficient low-latency uplink access
US10091812B2 (en) 2015-01-15 2018-10-02 Nokia Solutions And Networks Oy Method and apparatus for implementing low-latency and robust uplink access
CN105722142A (zh) * 2016-02-26 2016-06-29 努比亚技术有限公司 移动终端及基于多链路的数据分流方法
CN105704717A (zh) * 2016-03-19 2016-06-22 广东嘉腾机器人自动化有限公司 一种agv通讯方法
CN105871924A (zh) * 2016-06-14 2016-08-17 深圳力子机器人有限公司 一种基于udp的agv小车通信方法
CN106535207B (zh) * 2016-11-04 2017-12-08 中国科学院上海微系统与信息技术研究所 一种小型化多业务无线移动自组网网络系统
KR102779486B1 (ko) * 2017-02-24 2025-03-12 삼성전자 주식회사 전자 장치 및 액세스 포인트 장치의 설치에 적합한 위치를 결정하는 방법
CN107040284B (zh) * 2017-03-27 2020-10-02 西安电子科技大学 一种提高数据传输的可靠性与稳定性的多址接入方法
CN107302575B (zh) * 2017-06-19 2020-02-18 深圳市盛路物联通讯技术有限公司 一种同步物联网接入节点与汇聚单元时间的方法及系统
CN109963302A (zh) * 2017-12-25 2019-07-02 富士通株式会社 确定无线网接入点的数量的方法、装置和终端设备
CN111669830B (zh) * 2020-05-19 2023-07-25 上海芯袖微电子科技有限公司 一种wlan通信方法及装置
US11751056B2 (en) 2020-08-31 2023-09-05 Oracle International Corporation Methods, systems, and computer readable media for 5G user equipment (UE) historical mobility tracking and security screening using mobility patterns
US11825310B2 (en) 2020-09-25 2023-11-21 Oracle International Corporation Methods, systems, and computer readable media for mitigating 5G roaming spoofing attacks
US11832172B2 (en) 2020-09-25 2023-11-28 Oracle International Corporation Methods, systems, and computer readable media for mitigating spoofing attacks on security edge protection proxy (SEPP) inter-public land mobile network (inter-PLMN) forwarding interface
CN112152863B (zh) * 2020-10-21 2022-05-24 新华三信息安全技术有限公司 分布式带宽分配方法及装置
US11622255B2 (en) 2020-10-21 2023-04-04 Oracle International Corporation Methods, systems, and computer readable media for validating a session management function (SMF) registration request
US11528251B2 (en) * 2020-11-06 2022-12-13 Oracle International Corporation Methods, systems, and computer readable media for ingress message rate limiting
US11770694B2 (en) 2020-11-16 2023-09-26 Oracle International Corporation Methods, systems, and computer readable media for validating location update messages
US11818570B2 (en) 2020-12-15 2023-11-14 Oracle International Corporation Methods, systems, and computer readable media for message validation in fifth generation (5G) communications networks
US11812271B2 (en) 2020-12-17 2023-11-07 Oracle International Corporation Methods, systems, and computer readable media for mitigating 5G roaming attacks for internet of things (IoT) devices based on expected user equipment (UE) behavior patterns
US11700510B2 (en) 2021-02-12 2023-07-11 Oracle International Corporation Methods, systems, and computer readable media for short message delivery status report validation
US12080296B2 (en) * 2021-03-16 2024-09-03 Lenovo (Singapore) Pte. Ltd. Apparatus, method, and program product for performing a transcription action
US11689912B2 (en) 2021-05-12 2023-06-27 Oracle International Corporation Methods, systems, and computer readable media for conducting a velocity check for outbound subscribers roaming to neighboring countries
CN113316137B (zh) * 2021-05-28 2022-11-22 韦华半导体(苏州)有限公司 基于tdma的多频冗余无线传输方法及装置
CN115834000B (zh) * 2021-09-17 2024-04-19 中国科学院沈阳自动化研究所 一种面向工业无线下行传输的可靠重传方法
US12015923B2 (en) 2021-12-21 2024-06-18 Oracle International Corporation Methods, systems, and computer readable media for mitigating effects of access token misuse

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101500314A (zh) * 2009-03-17 2009-08-05 西南大学 工业无线网络的多发多收通信调度方法
CN101651969A (zh) * 2009-09-14 2010-02-17 西安交通大学 基于时分多址(tdma)的功率控制认知mac协议的实现方法
CN102118849A (zh) * 2011-03-02 2011-07-06 重庆邮电大学 一种适用于无线传感器网络的时间同步方法
CN102340819A (zh) * 2011-09-19 2012-02-01 中国科学院深圳先进技术研究院 传感器网络无冲突传输方法和系统
CN102404855A (zh) * 2011-12-02 2012-04-04 上海工业自动化仪表研究院 一种基于ieee 802.15.4的无线传感器网络协议
CN102413581A (zh) * 2011-12-02 2012-04-11 电信科学技术研究院 一种初始接入节点预约信道时隙的方法及系统

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6301242B1 (en) * 1998-07-24 2001-10-09 Xircom Wireless, Inc. Communication system with fast control traffic
JPWO2005081459A1 (ja) * 2004-02-25 2007-10-25 独立行政法人情報通信研究機構 無線アクセス方法及びシステム
US7813382B2 (en) * 2005-09-30 2010-10-12 Robert Bosch Gmbh Method and system for time synchronization in communication networks
US9461736B2 (en) * 2006-02-21 2016-10-04 Qualcomm Incorporated Method and apparatus for sub-slot packets in wireless communication
US8880104B2 (en) * 2006-03-03 2014-11-04 Qualcomm Incorporated Standby time improvements for stations in a wireless network
US20070263616A1 (en) * 2006-05-15 2007-11-15 Castro Paul C Increasing link capacity via traffic distribution over multiple WI-FI access points
KR100776794B1 (ko) * 2006-12-08 2007-11-19 한국전자통신연구원 무선 개인영역 네트워크에서 무선 자원 할당 방법 및 그시스템
US7936709B2 (en) * 2008-03-18 2011-05-03 Mitsubishi Electric Research Laboratories, Inc. Distributed beacon enabled wireless networks
US8699411B1 (en) * 2009-09-30 2014-04-15 Google Inc. Dynamic TDMA system for TV white space MIMO wireless
CN102042030B (zh) * 2010-12-17 2012-07-04 华中科技大学 基于无线传感器网络的施工隧道安全防护方法及监控系统
CN103748852A (zh) * 2011-03-11 2014-04-23 美国汉物天公司 WirelessHART设备整合到有线HART网络的方法和设备
US8929215B2 (en) * 2011-10-29 2015-01-06 Ofinno Technologies, Llc Special subframe allocation in heterogeneous network
JP5898376B2 (ja) * 2012-04-30 2016-04-06 インターデイジタル パテント ホールディングス インコーポレイテッド ＣＯＢＲＡ（ｃｏｏｒｄｉｎａｔｅｄｏｒｔｈｏｇｏｎａｌｂｌｏｃｋ−ｂａｓｅｄｒｅｓｏｕｒｃｅａｌｌｏｃａｔｉｏｎ）動作をサポートする方法および装置

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101500314A (zh) * 2009-03-17 2009-08-05 西南大学 工业无线网络的多发多收通信调度方法
CN101651969A (zh) * 2009-09-14 2010-02-17 西安交通大学 基于时分多址(tdma)的功率控制认知mac协议的实现方法
CN102118849A (zh) * 2011-03-02 2011-07-06 重庆邮电大学 一种适用于无线传感器网络的时间同步方法
CN102340819A (zh) * 2011-09-19 2012-02-01 中国科学院深圳先进技术研究院 传感器网络无冲突传输方法和系统
CN102404855A (zh) * 2011-12-02 2012-04-04 上海工业自动化仪表研究院 一种基于ieee 802.15.4的无线传感器网络协议
CN102413581A (zh) * 2011-12-02 2012-04-11 电信科学技术研究院 一种初始接入节点预约信道时隙的方法及系统

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP2897399A4 *

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