1. Fill in the blanks
1. The core and foundation of the Internet of Things ( Internet ).
2. The Internet of Things means that objects pass through intelligent sensing devices, pass through the transmission network, and reach the designated data processing center to realize information interaction and processing between people and people, things and things, and people and things (intelligent network ) .
3. The basic characteristics of the Internet of Things are ( comprehensive perception ), ( reliable transmission ), and ( intelligent control ).
Tip: Book P3——The Internet of Things is characterized by the ability to fully perceive objects, and the ability to reliably transmit and intelligently control information.
4. The Internet of Things is divided into three layers ( perception layer ), ( network layer ) and ( application layer ).
5. One of the technologies involved in the perception layer, RFID products have ( low frequency ), ( high frequency ), ( ultra high frequency ) frequency ranges.
6. The RFID system is mainly composed of ( reader ), ( electronic tag ), ( RFID middleware ) and ( application system software ) 4 parts. ( RFID and application system software are collectively referred to as application system )
7.RFID is divided according to the power supply method (Passive RFID products ), ( semi-active RFID products ), ( active RFID products ) three categories.
8.RFID can be divided according to the frequency of use ( low frequency 125kHz ), ( high frequency 13.56MHz ), ( ultra high frequency 860~960MHz ), ( microwave 2.45GHz and 5.8GHz ).
9. The electronic tag containing the chip basically consists of three parts: antenna , analog front end (RF front end) and control circuit .
10. The analog front-end (RF front-end) circuit mainly consists of two working modes ( inductive coupling ) and ( microwave electromagnetic backscattering ).
11. The EPC system is based on ( RFID ) (select RFID\sensor) IoT architecture.
12. Bluetooth works in the ( 2.4GHz ) ISM frequency band.
13. The range of the ISM frequency band in most countries around the world is ( 2.4~2.4835GHz ).
14. The two main technologies used by Bluetooth are ( circuit switching ), ( packet switching)), can transmit language and data services at the same time.
15. The language channel of Bluetooth is ( 64kbps ).
16. Bluetooth defines two link types: ( asynchronous connectionless link ACL ) and ( synchronous connection-oriented link SCO ). 17. Bluetooth devices can be divided into ( master device ) and ( slave device )
according to their roles in the network . 18. ( Piconet ) is the most basic Bluetooth network, consisting of a master device and other slave devices connected to each other. 19. Several piconets overlap each other in time and space, further forming a more complex network topology, called ( scatternet ). 20. When the Bluetooth device is in the communication connection state, there are four working modes: activation (Active) , breathing (Sniff) , hold (Hold) , and sleep (Park) . 21. Bluetooth works in the global 2.4GHz-ISM frequency band, and uses ( frequency hopping) technology transceivers to achieve anti-interference and suppress signal attenuation. 22. The most notable features of ZigBee technology are ( low power consumption ) and ( low cost ).
23. ZigBee mainly adopts ( star network ), ( tree network ) and ( mesh network ) three networking methods.
24. At the network layer, ZigBee mainly defines 3 roles ( network coordinator ), ( router ), and ( end device ).
2. Multiple Choice Questions
1. Bluetooth defines two link types, which are used to transmit languages, and those that support symmetric, circuit switching and point-to-point connections are (B).
A.ACL B.SCO C.EPC D.RFID
2. Bluetooth defines two Among the link types, which are used to transmit data, support symmetric and asymmetric, packet switching and multi-point connections are (A).
A.ACL B.SCO C.EPC D.RFID
3. Each ZigBee network can support up to ( A) Devices.
A.255 B.254 C.65000 D.920
4. The main node in the ZigBee network can also be managed by the network nodes of the upper layer, which can form a large network of (C) nodes at most.
A.255 B.254 C.65000 D.920
5.ZigBee is a wireless data transmission network platform composed of up to (C) wireless data transmission modules.
A.255 B.254 C.65000 D.920
6.ZigBee star network does not support (D).
A.ZigBee connector B.ZigBee terminal C.ZigBee coordinator D.ZigBee router
3. Multiple Choice Questions
1. When the Bluetooth device is in the communication connection state, there is a low power consumption mode (BCD) for energy saving.
A. Activate B. Breathe C. Hold D. Dormant
2. The following are the technologies for short-distance communication (ABC).
A.Zigbee B.WIFI C.Bluetooth D.Ultra Wideband Technology
3. The characteristics of ZigBee technology are (ADE).
A. Low power consumption B. High cost C. High data transmission rate D. Large capacity E. Short delay
4. ZigBee provides (ABC) these three raw data throughput rates.
A.250kbps(2.4GHz) B.40kbps(915MHz) C.20kbps(868MHz) D.220kbps(2.2GHz)
5. The range of ISM frequency bands in most countries in the world is 2.4~2.4835GHz, of which ISM frequency bands are: global (1), the United States (2), and Europe (3). (B)
A. 915MHz 868MHz 2.4GHz
B. 2.4GHz 915MHz 868MHz
C. 13.56MHz 915MHz 868MHz
D. 915MHz 868MHz 13.56MHz
6. The carrier of Zigbee network and Bluetooth network has (40) channels, among which the broadcast channel is (37,38,39).
7. ZigBee network structure includes (BCD).
A.ZigBee connector B.ZigBee terminal C.ZigBee coordinator D.ZigBee router
4. Short answer questions
1. What is the definition and composition of the sensor? Its functions are respectively?
Answer: A sensor is a device or device that can sense a specified measured value and convert it into a usable signal according to certain rules, usually consisting of a sensitive element and a conversion element. A sensor is actually a functional block whose function is to convert various information from the outside world into electrical signals.
The sensitive element refers to the part of the sensor that can directly sense or respond to the measured .
The conversion element refers to the part of the sensor that can convert the measurand sensed or responded by the sensitive element into an electrical signal suitable for transmission or measurement.
2. What is the function of EPC code?
Answer: EPC coding is an important part of EPC. It is to code entities and related information of entities, and to establish a global information exchange language through unified and standardized coding.
3. The EPC system is an RFID-based Internet of Things architecture. What does its architecture mainly include? What role does each part play?
Answer: The EPC system consists of three parts: the global electronic product code (EPC) coding system, radio frequency identification system and information network system, mainly including EPC code , EPC radio frequency tag , EPC radio frequency reader , Savant management software , object naming analysis system ( ONS) , physical recognition language (PML) 6 aspects.
EPC coding is to provide a unique identification of objects in the physical world, to identify and access individual objects through computer networks, just like using IP addresses to identify, organize and communicate in the Internet.
The information network system is composed of the local network and the global Internet, and is a functional module to realize information management and information circulation. The EPC information network system is based on the global Internet, through Savant management software , Object Naming System (ONS) and Physical Identification Language (PML) , to achieve global "physical interconnection".
The EPC radio frequency identification system is a functional module to realize the automatic collection of product EPC codes, mainly composed of EPC radio frequency tags and EPC radio frequency readers. The radio frequency tag is the physical carrier of the electronic product code (EPC), which is attached to the trackable item and can be circulated globally and identified, read and written. The radio frequency reader is an electronic device used to identify EPC tags, and is connected to the information system to exchange data.
4. What is the architecture of ZigBee?
The ZigBee architecture mainly consists of a physical (PHY) layer, a media access control (MAC) layer, a network/security layer, and an application framework layer .
The IEEE 802.15.4 standard defines the PHY layer and MAC layer of the ZigBee protocol , and the ZigBee Alliance standardized its network layer protocol and API, and also developed a security layer, which really formed the ZigBee protocol stack.
The PHY layer is characterized by enabling and disabling wireless transceivers, energy detection, link quality, channel selection, clear channel assessment (CCA), and sending and receiving data packets over the physical medium.
The characteristics of the MAC layer are: beacon management, channel access, time slot management, sending confirmation frames, sending connection and disconnection requests. In addition, the MAC layer provides methods for applying appropriate security mechanisms.
The network/security layer is mainly used for the networking connection, data management and network security of ZigBee's LR WPAN network.
The application framework layer mainly provides some application framework models for the actual application of ZigBee technology, and the application frameworks provided by different manufacturers are different in different application occasions.
5. What is the architecture of wireless sensor network?
Answer: A wireless sensor network is a task-oriented wireless ad hoc network system, usually composed of a large number of sensor nodes densely deployed in a monitoring area and one or more data aggregation nodes located in or near the area. These sensor nodes integrate the functions of information collection, data processing and wireless communication, form a network through wireless communication and self-organization, monitor and process various environmental data or target information in the monitoring area, and combine the monitored data and The information is sent to the sink node. At the same time, the sensor node can also be connected to the existing network infrastructure (such as the Internet, satellite network, mobile communication network, etc.) through the aggregation node as a gateway, so as to transmit the collected data and information to the remote monitoring center or end users. use.
6. Please design an IoT application/describe an existing IoT application according to the three-tier structure framework of the IoT.
Answer: [This is written by myself] You can refer to Chapter 8 of the book