CIIT Attock

Wireless Sensor Networks

Assignment # 1

Aroosa AmanatMS-EE Fall 2016

9/12/2016

Department Of Electrical Engineering

COMSATS Institute of Information TechnologyAttock Campus

1

Briefly explain the following topics BACnet, Lon Works, KNX.

BACnet:

A data communication protocol for building automation and control networks. A data communication is set of rules governing the exchange of data over a computer network. BACnet is an American national standard, a European standard and a national standard in more than 30 countries. It is developed, supported and maintained by ASHARE (American society of heating, refrigeration and air-conditioning) and accepted as American standard in 1995.BACnet provides the communication infrastructure needed to integrate products made by different vendors and to integrate building services that are now independent. BACnet rules relates specifically to the need of building, equipment control and automation for example they define fan operating schedule, temperature measurements or send alarm. BACnet is based on a "client-server" model of the world, BACnet messages are called "service requests." A client machine sends a service request to a server machine that then performs the service and reports the result to the client. BACnet currently defines 35 message types that are divided into 5 groups or classes.

Lon Works:

Lon work (Local Operating Network) developed by Echelon is peer-peer network, meaning there is no single master on network. Each Lon Works node includes local processing and I/O to process input data from sensors, handle control of actuators, and interact with other devices. Each node also includes the capability to communicate with other nodes because it contains the Lon Talk protocol in firmware.

 The four major elements of Lon Works are the Lon Talk protocol, the Neuron chips, the Lon Works transceivers, and network management and applications software. The Lon Talk protocol is a 7-layer communications protocol which ensures that nodes can inter-operate using an efficient and reliable communications standard. Neuron chips works whenever a node program writes a new value into one of its output variables, the new value is propagated across the network to all nodes with input network variables connected to that output network variable. Lon Work transceivers includes 74-kbps twisted-pair transceivers, power line transceivers, radio frequency transceivers and link-power twisted-pair transceivers etc. The software program of Lon Work network is the Lon Maker Integration Tool which uses the Microsoft Visio graphic interface.

KNX:

KNX the worldwide standard for home and building control. This standard is based upon more than 24 years of experience in the market.Via the KNX medium to which all bus devices are connected (twisted pair, radio frequency, power line or IP/Ethernet), they are able to exchange information. Bus devices can either be sensors or actuators needed for the control of building management equipment such as: lighting, blinds / shutters, security systems, energy management, heating, ventilation and air-conditioning systems etc. All these functions can be controlled, monitored and signaled via a uniform system without the need for extra control centers. KNX is an approved international standard as well as European standard and Chinese standard.

2

Figure 1 KNX

Give some Examples of Semi Passive Sensors?

RFID tags can be active, passive and semi-Passive. In Semi Passive RFID the battery is only used to power the sensor and recording the logic whereas communication in active RFID powered by his own battery. Implementation of active RFID requires larger battery and more electronic component. The typical range of Passive and Semi Passive RFID is 10cm-3m and that of active RFID is 100 meters. The price of active RFID is ten times of semi-passive RFID. Recently commercially Semi-Passive Temperature, humidity, shock and light sensors are available. Example of a semi-passive sensor is an inertial sensor integrated into a shoe could measure the daily walking distance, and the result could be read from the sensor at the end of the day by an NFC-enabled mobile phone.