ZigBee原理、技术和应用(2).ppt

,ZigBee原理、技术和应用,ZigBee 简介ZigBee 是一种新兴的短距离、低功耗、低数据速率、低成本、低复杂度的无线网络技术；ZigBee 采取了 IEEE 802.15.4强有力的无线物理层所规定的全部优点：省电、简单、成本又低的规格；ZigBee增加了逻辑网络、网络安全和应用层；ZigBee 的主要应用领域包括无线数据采集、无线工业控制、消费性电子设备、汽车自动化、家庭和楼宇自动化、医用设备控制、远程网络控制等场合；ZigBee 无线 可使用的频段有 3 个，分别是 2.4GHz 的 ISM 频段、欧洲的868MHz 频段、以及美国的 915MHz 频段，而不同频段可使用的信道分别是 16、1、10 个，在中国采用2.4G频段，是免申请和免使用费的频率。,Lighting,profile,Lighting,profile,ZigBee Promoters,Members are many more,ZigBee联盟简介,ZigBee联盟组成,成立于2001年9月,成员为半导体厂商、无线IP供应商、OEM厂商及终端用户 拥有150个成员，包括飞思卡尔、菲利普、三菱、三星、IBM,及华为等,ZigBee联盟的宗旨,在一个开放式全球标准的基础上使稳定的、低成本的、低功,耗的、无线联网的监控和控制产品成为可能,ZigBee 技术优势,ZigBee 通信可靠性,ZigBee 物理层上的设计保证了较强的抗干扰能力和通信可靠性；,ZigBee 技术在通信协议上的可靠设计，保证了较强的抗干扰能力和通信可靠性。,ZigBee 工作过程,操作状态,Active Sleep,设备类型,全功能设备(FFDs)精简功能设备(RFDs),所有设备遵守IEEE编址规范,运行模式 Beacon,Non-beacon,Slide Courtesy of,ZigBee Mesh 网络,Source:http:/www.zigbee.org/en/resources/#SlidePresentations,Slide Courtesy of,Source:http:/www.zigbee.org/en/resources/#SlidePresentations,ZigBee Mesh 网络,Slide Courtesy of,Source:http:/www.zigbee.org/en/resources/#SlidePresentations,ZigBee Mesh 网络,Slide Courtesy of,Source:http:/www.zigbee.org/en/resources/#SlidePresentations,ZigBee Mesh 网络,Slide Courtesy of,Source:http:/www.zigbee.org/en/resources/#SlidePresentations,ZigBee Mesh 网络,ZigBee 应用领域,ZigBee,简单有效的无线控制手段,车辆监控,電子消費產品,電視錄像機DVD/CD无线遙控器,電腦設備,工業自动控制,宇自動化,保安系統大型空調系統自動讀表系統照明控制門禁系統,病人監護系統健身監察系統保健資產监控管理生產過程監控環境及能源管理,ZigBee 应用,Home automation,03/03/2009:RF4CE Consortium,founded by Panasonic,Corporation,Royal Philips Electronics,Samsung Electronics Co.,Ltd.and Sony Corporation,have reached an agreement to deliver,a standardized specification for radio frequency-based(RF),remote controls,Wireless thermostat,Wireless mini touch screen,Wireless switchesWireless dimmerContact/Relay Extender:Makes wired contactswireless,Remote control,Digital amplifier,home music distribution,ZIGBEE应用-RFID数据远程传输,由于RFID的传输距离相对比较近，利用ZIGBEE无线网络作为RFID的远程无线传输网络，可以很好地结合RFID和ZIGBEE的技术优势，组合成一个比较完美的RFID应用系统。,ZIGBEE应用-医院医疗监护,利用ZIGBEE 技术组成一个网状路由网络，在楼道设置合适的路由节点，进行数据的中转；,房间内的呼叫节点采用星型网络连接，由其中一个节点作为ZIGBEE 路由器，负责与中心网络的连接和数据中继转发；,所有的 ZIGBEE 路由器组成一个蜂窝网状网络，再与 ZIGBEE 中心节点连接，中心节点设置在管理中心，构建成一个完整的 ZIGBEE无线网络,ZIGBEE应用-远程抄表,将 zigbee 技术与 GPRS/CDMA 结合起来，根据抄表用户的不同分布，来灵活地构建抄表的无线网络；,对于每个抄表终端，要求超低功耗、低成本，并且数据的传输速率不高；,对于居民小区的抄表，抄表终端通常分布较密集、距离较近，zigbee 技术可以很好地满足这些要求；,终端采集的数据需要送到电力公司的集抄管理中心，这可以通过 GPRS/CDMA 网络来实现，它无距离限制。,ZigBee协议栈APS：Application interface designed using general profileNWK：Topology management,MAC management,routing,discovery protocol,security managementMAC：Channel access,PAN maintenance,reliable data transportPHY：Transmission&reception on the physical radio channel,SAP=Service,Access Point,DE=Data Entity,ME=Mgmt Entity,ZigBee协议栈,ZigBee Technology Provides network,security management,applications profiles,interoperability andcertification testingIEEE STD 802.15.4 Designed to supply theradio and protocol,allowing the designer,to concentrate on theapplication and theircustomers needs,Application/ProfilesApplication FrameworkNetwork/Security LayersMAC LayerPHY Layer,ApplicationZigBeeTM Platform StackSilicon,ZigBeeTMZigBeeTMAlliancePlatformIEEE,S1,ZigBee网络模型ZigBee技术具有强大的组网能力，可以形成星型、树型和MESH网，可根据实际需要来选择合适的网络结构；MESH 网状网络拓扑结构的网络具有强大的功能，网络可以通过“多级跳”的方式来通信；该拓扑结构还可以组成极为复杂的网络；网络还具备自组织、自愈功能；星型和族树型网络适合点对多点、距离相对较近的应用。ZigBee 网络协调器(FFD)ZigBee Router(FFD)ZigBee End Device(RFD or FFD),Cluster Tree Routing,Mesh Routing,ZigBeePRO:Mesh&Many-to-One routing as a special case of Mesh,PHY layer,This standard provides 2 PHY options with frequency band asfundamental difference.,2.4 GHz band has worldwide availability and provides a transmission rateof 250 kb/s.,The 868/915 MHz PHY specifies operation in the 868 MHz band inEurope and 915 MHz ISM band in the United States and offer data rates20 kb/s and 40 kb/s respectively.,Different transmission rates can be exploited to achieve a variety ofdifferent goals.,Channelization,27 frequency channels are available across all the 3 bands.,This standard includes the necessary things to implement dynamicchannel selection to avoid interference.,The PHY layers contain several lower-level functions,such as receiverenergy detection,link quality indication,and channel switching,whichenable channel assessment.,These functions are used by the network to establish its initial operatingchannel and to change channels in response to a prolonged outage.,4 Octets,0-127 Bytes,1 Octets,1 Octets,物理层帧格式物理层报文 前导(32 bits)用于同步 Start of packet delimiter(8 bits)shall be formatted as“11100101”物理层头(8 bits)PSDU 长度、预留一位 PSDU(0 to 127 bytes)数据域,Modulation,Data link layer.,IEEE 802 splits DLL into MAC and LLC sublayers.,LLC is standardized and is common in 802.3,802.11,802.15.1.,features of the IEEE 802.15.4 MAC are association and disassociation,acknowledged frame delivery,channel access mechanism,framevalidation,guaranteed time slot management,and beaconmanagement.,MAC,MAC provides data and management services to upper layersThe MAC management service has 26 primitives whereas 802.15.1has about 131 primitives and 32 events,802.15.4 MAC is of very low complexity,making it very suitable for itsintended low-end applications,albeit at the cost of a smaller feature setthan 802.15.1(e.g.,802.15.4 does not support synchronous voicelinks).,IEEE 802.15.4 帧格式,Data payload:127bytes,Security:AES with symmetric keys(link or group keys)to provideData Integrity,Data Confidentiality,Replay Protection,MAC,Layer,PHY Layer,IEEE 802.15.4 MAC OverviewGeneral Frame StructurePayload,MAC Header(MHR),MAC Footer(MFR),MAC Protocol Data Unit(MPDU),MAC Service Data Unit(MSDU),PHY Header(PHR),Synch.Header(SHR),PHY Service Data Unit(PSDU)4 Types of MAC Frames:Data Frame Beacon Frame Acknowledgment Frame MAC Command Frame,Slide 28,Joe Dvorak,Motorola,9/27/05,超帧结构,使用分时隙的,CSMA/CA超帧(分时隙模式，Slotted Mode),协调器分配,Active可以划分16个时隙，第一个时隙是信标时隙，这16个时隙又可分为竞争阶段（CAP)和非竞争阶段（CFP)CAP(Contention Access Period)-CSMA/CACFP(Contention Free Period)(7slots),分配GTS給有数据交换需求的设备Inactive是指不可以传输数据的时间,超帧结构Super Frame(Slotted Mode),启动superframe同步网络中的设备通知网络外的设备，当前存在由本协调器形成的PAN协调器通知设备，有数据传输给它,超帧结构Beacon的功能,BO決定superframe的长SO決定superframe中，active阶段的长,0SOBO14,超帧结构Superframe的长取决于如下参数,分时隙CSMA/CA,optional,UnslottedCSMA/CA,There is no conceptof CW in this part.,ZigBee设备模型,技术比较,ZigBee由ZigBee由,在树状网络中，用指派位址的方式寻。网状网络中，用类似AODV的方法寻。,NWK802.15.4,NWK802.15.4,APP1,NWK802.15.4,APP2,APP2,APP3,Cluster1,Cluster2,App profile 1,Cluster1,Cluster2,App profile 1,APS,APS,IPPHY/MAC,UDP/TCP,Message RoutingEndpoints have to be bound before one sends messagesto the otherFor comparison:Java,Thread on a UDP/TCP/IPmachine,Java Classes/Interfaces,JavaThreads,ZigBee Application ModelApplication Profiles are an agreement on a series of messagesdefining an application space(for example,“Home Automation”or“Smart Energy”)Endpoints are a logical extension added to a single ZigBee radiowhich permits support for multiple applications,addressed by theEndpoint number(1-240).Key Relationships:,Maximum of 240 Endpoints per ZigBee Device(Endpoint 0 isreserved to describe the generic device capabilities and Endpoint255 is reserved for broadcasting to all endpoints,Endpoints 241-254 are reserved for future use)One Application Profile described per Endpoint,Cluster:A cluster is a related collection of commands andattributes,which together define an interface to specific functionality,Something similar to a Java class with member variables,membermethods and interfaces,ZigBee Device Objects(ZDO),ZDO is responsible for:,Initializing the application support sub-layer(APS),thenetwork layer(NWK),and the Security Service Provider.Assembling configuration information from the end,applications to determine and implement:,Discovery(device discovery,service discovery)Security managementNetwork managementBinding management,Application Support Sublayer(APS)Functionality similar to TCP/IP,Generation of the application level PDU(APDU)BindingGroup address filteringReliable transportDuplicate rejectionFragmentation,ZigBee Cluster Library(ZCL)A Cluster is a related collection of commands andattributes,which together define an interface to specificfunctionality.Clusters are distinguished by ID numbers(16-bit integers)Client-Server Semantics Cluster Server:Entity that stores the attributes of a cluster Cluster Client:Entity that affects or manipulates thoseattributesCommands:Manipulate(Read/Write/Etc)Attributes onServerCommands,ResponsesCluster Binding,Any DeviceCClient,Any DeviceSServer,ZigBee Cluster Library(ZCL),Commands:Read attributes:Specify a list ofattribute IDs to be read Write attributes:Specify a list of,attributeid-type-value triples to bewrittenWrite attributes undivided:Sameas above but the operation fails ifany of the attributes cannot bewritten(atomicity)Configure reporting:Specifyreporting frequency,eventthresholds.,Events are specified usinga change value(+/-change)and checkperiod.E.g.send a reportif attribute#124 changes+/-4 units and check againif it changes after 30seconds(essentiallyconfigure a check period),Read reporting configurationReport attributes:The actual reportmessage with the attributeid-type-value triple which is the result of theConfigure reporting commandDiscover attributes:A noderequests from another to list theattributeids that it stores,Responses Read attributes response Write attributes response,Write attributes no responseConfigure reporting responseRead reporting configurationresponseDefault responseDiscover attributes response,ZigBee Cluster Library(ZCL)contdEach cluster has specific attributes listed in the standard“Attributes”are basically attribute ID-value pairs to(e.g.sensed values forsensors),Attributes dont have names,they have 16-bit IDsAttributes have values with specific data types dictated in the standard,Example a temperature value may be encoded as a 16-bit etc signedintegerExample:If one application on one node wants to read the temperature of atemperature sensor on a another node then it has to send the command toread the attribute“temperature”which has an attribute ID 124.Access control classification of attributes:,“Read Only”if they can only be read(e.g.a measured sensor value)“Read/Write”if they be read or written(e.g.configuration or actuation settings).,Compliance classification of attributes,Mandatory:if the standard mandates the existence of the attribute on thedevice that implements a specific cluster which includes the attribute in questionOptional:if the standard allows devices not to include the specific attribute intheir cluster implementation.,DeploymentCommissioning,Devices are programmed for a specific feature set or to join specific,alternate feature set networksIf multiple networks with the same feature set are present,theapplication needs mechanisms to help the device select the correctnetwork,Provision security keys(unless they are provided over the air)Establish command/control relationships in the network(binding)Commissioning can take place via a dedicated commissioning tool,(laptop or PDA)or via installation key presses on a remote controlor the device itselfCommon Maintenance Operations requiring application support,Adding new devices to an existing networkCombining networksReplacing devices in a network,ZigBee Frame Formats,APS FrameFormatNWK FrameFormatPHY/MACFrameFormat,ZigBee Frame Formats(contd),Command Frame Format:command id=00=Command=Read attributesZCL Frame formatAPS FrameFormat,Q&A,