IOT_WIFI/LORA/THREAD/ZIGBEE/NFC/RFID/EnOcean

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What is IoT?

IoT stands for interconnection of internet enabled devices or things unlike people only connectivity used in today’s internet. Due to huge growth in demand for IoT compliant devices chip makers are having great future ahead. IoT is the short form of Internet of Things. According to cisco and other organizations there will be about 50 billion devices connected using internet in the year 2020. Devices based on ethernet, zigbee, bluetooth and wifi will have huge requirements in consumer electronics segment. Cellular devices based on GSM and LTE also will be available to have connectivity with cellular wireless networks,

IoT Applications

IoT devices are used for following applications:
• In consumer market for smart home control(lighting,security,comfort),Optimized energy use maintenance.
• In Industrial market for smartmeters, Wear-out sensing devices, Manufacturing control, Climate control
• In Automotive industries for parking, traffic flow control, Anti-theft devices, Location tracking etc.
• In Environmental for species tracking, weather prediction and resource management.
• In agriculture market for crop management and soil analysis.
• In military for resource allocation, threat analysis, troop monitoring etc.
• In medical industry for wearable devices, implanted devices and telehealth services.
• In retail for product tracking, Inventory control, focused marketing, etc.

IoT Entities

There are two major subsystems involved in the IoT network viz. front end part and back end part. Front end is mainly consists of IoT sensors which are MEMS based. It includes optical sensors, light sensors, gesture and proximity sensors, touch and fingerprint sensors, pressure sensors and more.

Back end consists of cellular, wireless and wired networks which are interfaced with IoT devices. The devices will report to the central servers and also interact with databases in the backbone network. Routers and gateways are part of the wireless backbone networks.

IoT Protocol layers

As the standard has not been finalized for IoT but one can think of IoT having 4 protocol layers as shown in the figure-2. Sensing and Identification include various smart sensor devices based on GPS, RFID, WiFi etc. Network connectivity layer is based on wired and wireless network such as WLAN, WPAN, WMAN, ethernet, optical fiber and more.Other two layers are information Processing layer and application layer.

Cellular IoT

Wireless cellular companies are working towards providing collectivity and enhancement to existing wireless devices to support emerging IoT market.

IoT Device and components

The IoT device mainly consists of battery for providing power. It should have long life approx. about 10 years. The parts include interfacing with sensors and connectivity with wireless and wired network. Hence it include small part of physical layer and also upper protocol layers to interface with application layer. Devices should support both IPV4 and IPV6 based IP protocols. IoT devices must have receiver sensitivity atleast 20dB better than non-IoT devices. The IoT devices should be cheaper about less than $10.

IoT Wireless Technologies

THREAD

What is THREAD

Following wireless home network requirements for connected devices lead to the development of new technology known as thread.
• Low Power
• Resilient (mesh network)
• IP based
• Open protocol
• secure and user friendly
• Fast time to market
• Existing radio silicon
The thread technology is mainly targetted for M2M and IoT market. It is based on existing 802.15.4 standard. A software upgrade to existing 802.15.4 products can add thread features.

THREAD basics in M2M and IoT

Following are the silent features of Thread.
• Uses 6LoWPAN and carries IPv6 packets
• Runs on existing 802.15.4 silicon
• New security architecture introduced to support easy addition and removal of security products.

Figure depicts thread protocol stack which mentions layers added for this technology to exist. It supports many application layers including low bandwidth ones which runs over Ipv6 protocol.

This Thread technology is designed and developed to support following products to be used in the home.
• Security products
• Safety products
• Lighting products
• Energy management products
• climate control products
• Access control products
• Home or household appliances

Some of products which uses thread technology are as follows:
• CoAP and Smart Objects
• ZigBee Smart Energy 2.0
• ECHONET Lite

WLAN

Introduction

Let us understand LAN first. LAN means Local Area Network. It is connection of more than one computer using some medium. For the case of LAN this medium will be wired which include Ethernet cable, fiber optic etc. As shown in figure on the left side LAN can be formed using either Ethernet switch or hub or router. All the computers are connected with this switch/Hub/router. This Switch/Hub/router is connected with cable modem provided by ISP(Internet Service Provider). Cable modem connects with ISP’s Web server i.e. Internet. The advantages of LAN are many such as speed of data communication (as Ethernet works at 10/100 Mbps), sharing of common resources such as printer, internet connection etc.

Basics of WLAN

WLAN is the short form of Wireless Local Area Network. Unlike LAN, WLAN will have Wireless medium which include radio wave, microwave etc. WLAN compatible Access points or routers are available which converts LAN to become WLAN. So that WLAN devices such as laptop, ipad, tablet can communicate any system in LAN. This wifi router is connected with cable modem on one side using cable. The other side of wifi router is wireless medium, by which it will connect with WLAN devices. There are various PC cards or USB dongles available with WLAN features so that they can be connected with WiFi network or WLAN network. The same is depicted in the figure on right hand side (laptop with wireless adapter card).

Wireless LAN works on radio frequency of usually around 2.5GHz or 5GHz. There are different flavors in WLAN for different data rates and distance coverage. They are 11a, 11b, 11g, 11n, 11ac, 11ad etc. developed and maintained by IEEE and popularly called as IEEE Standards. These IEEE standards define PHY and MAC layers of 11a/11b/11g/11n/11ac/11ad and upper layers are developed by IETF.
WLAN is the short form of Wireless Local Area Network. Unlike LAN, WLAN will have Wireless medium which include radio wave, microwave etc. WLAN compatible Access points or routers are available which converts LAN to become WLAN. So that WLAN devices such as laptop, ipad, tablet can communicate any system in LAN. This wifi router is connected with cable modem on one side using cable. The other side of wifi router is wireless medium, by which it will connect with WLAN devices. There are various PC cards or USB dongles available with WLAN features so that they can be connected with WiFi network or WLAN network. The same is depicted in the figure on right hand side (laptop with wireless adapter card).

Wireless LAN works on radio frequency of usually around 2.5GHz or 5GHz. There are different flavors in WLAN for different data rates and distance coverage. They are 11a, 11b, 11g, 11n, 11ac, 11ad etc. developed and maintained by IEEE and popularly called as IEEE Standards. These IEEE standards define PHY and MAC layers of 11a/11b/11g/11n/11ac/11ad and upper layers are developed by IETF.

WLAN Standards

WLAN devices are designed and developed as per IEEE standards. There are different versions based on RF frequency, data rate and coverage requirement. They are IEEE-802.11a, IEEE-802.11b, IEEE-802.11g, IEEE-802.11n, IEEE-802.11ac, IEEE-802.11ad etc. developed and maintained by IEEE. These IEEE standards define PHY and MAC layers of 11a/11b/11g/11n/11ac/11ad and upper layers are developed by IETF. Wireless LAN works on radio frequency of usually around 2.5GHz or 5GHz.

IEEE 802.11a- This wlan standard supports OFDM Physical layer and works at 5 GHz RF center frequency.
IEEE 802.11b- This wlan standard supports DSSS/CCK Physical layer.
IEEE 802.11g- This wlan standard supports both 11a and 11b and supports RF center frequencies of 2.4 GHz and 5 GHz.
IEEE 802.11n - This wlan supports OFDM and also MIMO is supported to enhance the data rate. It has 40MHz bandwidth supported.
IEEE 802.11ac- This wlan standard further extends bandwidth and increases MIMO antennas to further increase data rate compare to 11n.
IEEE 802.11ad- This wlan standard makes possible wlan devices to operate in 60GHz frequency band.

WLAN Devices

Hence in WLAN network there are two main devices, They are Access point (or router) and Station ( or client) . Both AP and STA should be WLAN standard compliant in order to establish WiFi or WLAN Network.

WLAN Frame

WLAN frame consists of preamble, PLCP header and Data (MAC PDUs). PLCP Header provides information (e.g. length, modulation, code rate) of DATA Burst. Data MAC PDU is composed of Header, Payload and CRC. Header provides many useful fields. Out of which are Type and Subtype fields. Type differentiates between three main types of frames used in wlan. They are control frame, data frame and management frame. Control frame helps in carrier sense and channel acquisition process to STA. This is done by way of RTS/CTS/ACK sub frames under control frame category. Data frames as the name suggests are used by STA for data communication. Management frames are used to establish the connection and to maintain the connection.

WLAN network establishment

As mentioned below there are various frames exchanged between STATION and Access Point to establish wlan network connection.

STA side - AP side

Probe REQ->
<-Probe RES
ACK (Acknowledgement)->
Authentication->
<-ACK
<-Authentication
ACK->
Association Request->
<-ACK
<-Association Response
ACK->
Data->
<-ACK

WLAN channels

Works on 2.4 GHz and 5 GHz RF center frequencies with various Channel bandwidths as shown below.
11b channels-Non overlapping (22MHz bandwidth), North America
Channel 1- 2412 MHz
Channel 6- 2437 MHz
Channel 11- 2462 MHz
11b channels-Non overlapping (22MHz bandwidth), Europe (except France and Spain)
Channel 1- 2412 MHz
Channel 7- 2442 MHz
Channel 13- 2472 MHz
11n channels-40MHz bandwidth, occupied bandwidth of 33.75 MHz
Channel 3- 2422 MHz
Channel 11- 2462 MHz
11 g/11n -20 MHz bandwidth, occupied bandwidth of about 16.25 MHz
Channel 1 - 2412 MHz
Channel 5 -2432 MHz
Channel 9 -2452 MHz
Channel 13 -2472 MHz

Applications of WLAN

It extends LAN by way of adding additional PCs(with WLAN PCI card) and other WLAN devices(laptop/ipad/tablet) using wireless connectivity.
It provides connection of two LANs housed in two nearby buildings
Wifi hot spots are available in park/coffee shop/malls, which provides visitor with wlan or wifi capable device to use internet.
Adhoc networking of devices temporarily without need of any server.Here all the devices(peers) communicate directly.

LORA

What is LoRa wireless?

LoRa stands for Long Range Radio. It is the wireless technology mainly targetted for M2M and IoT networks. This technology will enable public or multi tenant networks to connect multiple applications running in the same network. This LoRa technology will fulfill to develop smart city with the help of LoRa sensors and automated products/applications.

LoRa Alliance formed to standardize LPWAN (Low Power Wide Area Network) for M2M/IoT. The prospective members in this alliance are Actility, Cisco, Bouygues Telecom, Proximus, SingTel, Semtech, Swisscom, IBM, SingTel, KPN etc. The LoRa Alliance will drive global success of LoRa Protocol i.e. LORA WAN.

LoRa wireless technology basics in M2M and IoT

Following table summarizes key features of the LoRa wireless technology such as range, standard, modulation scheme, capacity, physical layer etc.


Figure depicts LoRa network. It consists of two main entities such as Sensors (or nodes) and LoRa Gateway(or LoRa base station).

LoRa Products and LoRa device testing

Semtech corporation is leader in LoRa wireless technology based products. LoRa has introduced SX127x family of RF Transceivers for supporting LoRa technology for emerging M2M/IoT market. These transceivers operate in 860-1000 MHz and 137-960 MHz range. They have also introduced concentrator in the 860-1000 MHz frequency range.

Semtech also offers LoRa device evaluation and testing devices for 868 MHz band. LoRa base station is also developed by them. Moreover SemTech corporation has developed LoRa development kit useful for the LoRa development/manufacturing companies.

Difference between Lora, INSTEON, Z-wave, Zigbee, X10, HomePlug and other M2M IoT wireless technologies

One can easily derive difference between Lora and other wireless IoT technologies such as zigbee, z-wave, insteon, X10, Homeplug, EnOcean, Bluetooth etc.

As there are wireless devices designed and developed based on different wireless standards as outlined above, the biggest challenge is interoperability between these devices in the IoT network. The other challenge is interference among these devices due to frequency of operation either in the same band or nearby bands. The radiated power is also the critical factor to be considered for interference related issues.

ZIGBEE

Introduction

Now-a-days zigbee is becoming very popular for low data rate wireless applications. Zigbee devices are used everywhere including smart energy, medical and in home automation. In smart energy applications zigbee products are used to monitor and control use of energy and water, which helps consumers save energy and water and save money too. In medical field it is used to connect unlimited number of health monitoring devices and many more. In home automation it controls domestic lighting, such as switches, dimmers, occupancy sensors and load controllers.

It has two bands of operation 868/915MHz and 2450MHz. 868/915 band provides about 20-40Kb/s and 2450MHz band provides about 250 kb/s data rates. In addition to this uses zigbee end devices can go to sleep mode which saves battery consumption and it also takes care of security of the information owing to security layer.

Zigbee Network Overview

As mentioned in the network diagram, zigbee network is comprised of coordinator©, router® and end devices (E). Zigbee supports mesh-routing. For detailed information on routing protocol employed in zigbee, one may refer Ad-hoc on-demand Distance Vector Routing protocol (AODV protocol),
Coordinator:
• Always first coordinator need to be installed for establishing zigbee network service, it starts a new PAN (Personal Area Network), once started other zigbee components viz. router® and End devices(E) can join the network(PAN).
• It is responsible for selecting the channel and PAN ID.
• It can assist in routing the data through the mesh network and allows join request from R and E.
• It is mains powered (AC) and support child devices.
• It will not go to sleep mode.
Router:
• First router needs to join the network then it can allow other R & E to join the PAN.
• It is mains powered (AC) and support child devices.
• It will not go to sleep mode.
End Devices:
• It cannot allow other devices to join the PAN nor can it assist in routing the data through the network.
• It is battery powered and do not support any child devices.
• This may sleep hence battery consumption can be minimized to great extent. There are two topologies, star and mesh, as mentioned Zigbee supports mesh routing. PAN ID is used to communicate between zigbee devices, it is 16 bit number. Coordinator will have PAN ID set to zero always and all other devices will receive a 16 bit address when they join PAN. There are two main steps in completing Zigbee Network Installation. Forming the network by Coordinator and joining the network by Routers and End devices.

Forming the Zigbee Network

• Coordinator searches for suitable RF channel which is usable and not interfering with Wireless LAN frequencies in use. This is because WLAN also operates in the same 2.4GHz bands.This is done on all the 16 channels. It is also referred as energy scan.
• Coordinator starts the network by assigning a PAN ID to the network. Assignment is done in two ways. Manual (pre configured) and dynamic (obtained by checking other PAN IDs of networks already in the operation nearby so that PAN ID does not conflict with other networks). Here Coordinator also assigns network address to itself i.e. 0x0000.
• Now coordinator completes its configuration and is ready to accept network joining request queries from routers and end devices who wish to join the PAN.
• In addition to above, Coordinator© sends broadcast beacon request frame on remaining quiet channel. This is also referred as beacon scan or PAN scan. By this Coordinator receives PAN ID of routers® and end devices(E) present nearby. It also comes to know whether R/E allow join or not.
• Now R/E can join by sending association request to C. C will respond with association response.

Joining the Zigbee Network

• Let us examine how a router or end device joins zigbee network as part of zigbee tutorial. There are two ways to join a zigbee network viz. MAC association and network re-join.

• First one is implemented by device underlying MAC layer and second one is implemented by network layer, despite the name may also be used to join a network for the first time.

• MAC association can be performed between C and R/E or R and E or R and other R.

• Let us assume that Coordinator© has already established the PAN network. Hence next step for R or E is to find out whether C is allowing joining or not. So they do PAN scan or send beacon request frame.

• After they come to know that they can join the network, they will send association request frame and will join the network as soon as they receive the association response.

• As mentioned above whether or not C or R allow a new device to join depends on two main factors:
-Permit joining attribute
-Number of end device children it already has.
One of the applications of zigbee in home is that switch, speakers and lamp is controlled using zigbee technology.

zigbee protocol stack

zigbee IP consists of various protocol layers viz. physical layer(PHY), mac layer, network layer and application layer. IEEE 802.15.4 standard defined zigbee PHY and MAC specifications. Zigbee alliance specifies network and application layers.

Zigbee Physical Layer

There are two physical layer version in zigbee. These are categorized based on frequency band of use viz. 868/915MHz and 2450MHz. The figure depicts the same. Refer Zigbee PHY for more information on working of physical layer and function of its modules.

Zigbee MAC Layer

The figure depicts physical layer packet structure used to carry MAC frame of different types as per need.

Zigbee MAC frames include beacon, data, acknowledgment, MAC command and so on.

Zigbee Network Layer

Ad-hoc on-demand Distance Vector Routing protocol (AODV) is used at network layer.

Zigbee Application Layer Profiles

There are two main types of profile IDs viz. public profile and manufacturer specific profile used in zigbee application layer. The data transmission and reception in zigbee device occurs using application profile. They have specific IDs assigned with size of 16 bits. Public profile ranges from 0x0000 to 0x7fff where as manufacturer Specific Profile ranges from 0xbf00 to 0xffff. Public profiles are used in order to have interoperability between different OEM devices. Manufacturer specific profiles are used by OEMs which do not require any interoperability with other OEM products.

RFID

RFID Terminologies

RFID Tag- There are two types of tags, passive and active. Tags are used to identify people/device/object and tied with them. Active tags send radio waves to the RFID reader and hence will inform about its location. Passive tags reflect the radio waves transmitted by RFID reader and hence reader will come to know about location of the tags. Passive tag usually will have coverage of about 3-5 meters while active tag will have coverage of about 100meters. Active tag has power source. Passive tags do not have internal power source/battery. Hence passive tags rely on power of the active tag, which passive tags obtain wirelessly using E-M waves. class 1 generation 2 tags are backward compatible to generation 1 class 0 & class 1 RFID tags.
RFID tags can be divided into five classes as shown in the following table:

RFID reader- The readers usually are mainly active type and will read information either transmitted by RFID tags or reflected by them. RFID reader usually is interfaced with computer.

What is RFID?

RFID stands for Radio Frequency Identification. As mentioned RFID devices use radio frequency waves to communicate. The common method used to identify person/object is to use serial number for each tags. Other information can also be customized as per the requirement. RFID tag usually will have smaller micro-chip along with the antenna. RFID tags communicate with the reader with the help of antenna. The reader converts reflected or transmitted information from tags to useful digital information which can be further processed by software running in the computer. RFID works on different frequency bands, mainly in UHF frequency range.

RFID Frequencies

RFID network operates based on three main frequency bands mainly LF,HF and UHF. Following table summarizes these frequencies and their applications.

RFID network

There are two major factors which help building the RFID network, coverage and number of objects/people. Let us understand RFID with the example of school tracking. For school management RFID is mainly used for student attendance management and for their movement notification. All these via real time SMS or E-mail. Here each Student is given a RFID Badge. This badge will contain student photo and other vital information. As depicted in the figure, RFID tags provided to students communicate with RFID reader. This reader having TCP/IP features interfaced with LAN and LAN intern connects with the server. This server is interfaced with SMS gateway. This gateway takes care of delivering SMS/Email to the authorities/parents. As per the layout entry and exit points of the school premises are installed with RFID reader. Once the student enters/ leaves the school premises, the RFID reader will capture all the information and the data is given to server for validation. After validation, SMS or Email is generated and sent to the registered mobile.

To cater any requirements of the RFID, following factors are needed by system integrators or RFID suppliers.
1.How big is the Area? This required to decide RFID tag type active or passive.

2.Where do they want to track the objects/people? This helps in decoding RFID reader location as well as number of readers.

3.How many number of objects/people are there? This helps in designing data base requirement in the GUI software running in the system attached with the RFID reader.

4.How are tags to be embedded with objects/people? i.e. in ID card, wrist band or to be stitched in the uniform etc. This helps address the requirement accordingly.

RFID applications

• Production line management
• Access control
• Patient ID management
• Logistics and warehouse management
• Asset tracking
• Parking management

RFID cost

Typically RFID passive tag costs about less than a dollar and RFID active tag costs about 25 dollar. RFID reader comes with about 500-700 dollar depending upon the features.

RFID vendors

RFID vendors/manufacturers provide RFID tags and RFID readers, which need to be used for various RFID applications as mentioned. Refer RFID tag page for more information.

RFID standards

RFID Class-1 Generation-2 can be downloaded from following link(UHF Class 1 Gen 2 Standard v. 2.0.0 ):
https://www.gs1.org/sites/default/files/docs/uhfc1g2/uhfc1g2_2_0_0_standard_20131101.pdf

NFC

Near Field Communication is referred as NFC. The technology is similar to RFID standard. As we know there are two types of fields around the RF Antenna viz. near field and far field. Near field refers to the electromagnetic radiation near to the antenna(i.e. region upto 2D2/λ) and far field refers to EM radiation away from the antenna. NFC has become very popular as short distance communication(few millimeters) with very low data rate (few kbits/sec). NFC protocols are based on RFID standards published and outlined in ISO/IEC 18092.

NFC is used for wide variety of contactless applications which include access control in railways and in offices, healthcare, information exchange, payments as well as consumer electronics. NFC is basically a point to point way of communication. It always need initiator and target. There are two types of communication based on power. In active communication , initiator and target will generate the EM fields alternately and will communicate with each other. In passive mode, target will draw the power from NFC reader. In passive mode it is easy to make the NFC target with the use of sticker and no battery is neeeded.

NFC devices work based on inductive coupling. Induction is the production of electric current by passing a wire through a magnetic field(H). As we know NFC devices have coils built into them. A magnetic field from a NFC device generates power in these coils, which initiates the transmission of data over the radio waves. Both devices (target and initiator) share this power.

NFC Operating modes

There are three operating modes in the NFC technology. They are reader/writer, peer to peer and card emulation.

The reader/writer mode is compliant to ISO/IEC 14443 as well as FeliCa specifications. In this mode, NFC device can read the tag. The tag here usually is integrated in the smart poster or sticker.

The peer to peer mode is compliant to ISO/IEC 18092 standard specifications. In this mode, devices are self powered. Here both the devices communicate with each other and share the information. Users of this mode can exchange bluetooth or WLAN link establishment parameters as well as exchange data for example, digital photos or virtual business cards.

In card emulation mode, the data stored on the card is read by NFC reader. The card having this mode is referred as smart card and is used for various applications such as ticketing, payments, purchases, transit access control mechanism etc. In this mode, NFC compliant device communicates with the reader just like a smart card. This mode is a two way communication.

NFC Frequency and data rates

NFC operates in unlicensed ISM frequency band of about 13.56 MHz. It supports data rate of 106 Kbps , 212 kbps and 424 Kbps. NFC uses bandwidth of 14KHz to map data on the RF carrier. Sidebands of NFC RF modulated spectrum may extend upto +/- 1.8MHz.

NFC Applications

NFC has wide variety of applications. Few of them are summarized below. Following can be served with the use of NFC mobile phone and NFC smart cards.
• It is used at airport and railways for pass gate, to get information from smart poster, to get information from information kiosk, to pay bus or taxi fare.
• It is used in the vehicle to adjust the seat position, to open the door, pay parking fees etc.
• It is used in the office for entry and exit locations, exchange business cards, log in to the PC, print using copier machines etc.
• It is used in the restaurant to pay using credit card, get loyalty points, get and use coupon, share information and coupon among NFC users etc. Figure-2 depicts NFC compliant USIM.
• It is used at theater stadium at pass entrance, get event information and more.
• It is used for download and personalize the applications, check usage history, lock phone remotely and more.

All the products compliant to NFC use N-Mark. It is the global symbol for recognition as well as acceptance of NFC compatible short range wireless communication devices.

NFC Tag Types

There are four NFC tag types viz. Tag 1 type, tag 2 type, tag 3 type and tag 4 type.

Type 1 tag : It is based on ISO/IEC 14443A standard specifications. Ihis tag type-1 is read as well as read/Write capable. The size of the memory is between 96bytes to 2kbytes. The memory can be write protected. The data rate supported with this type 1 tag is 106 kbps. One such example manufactured is Innovision Topaz.

Type 2 tag : It is based on ISO/IEC 14443A standard. This tag also is read/write protected and is write protectable. The memory size available is between 48 bytes to 2 Kbytes. The data communication speed supported is about 106 kbps. The NFC tag type-2 is manufactured by NXP and are available as NXP Mifate ultralight.

Type 3 tag : It is based on JIS X 6319-4 standard and is popular in Japan. The tag can be either read & re-writable or read only. This mode is pre-configured during the manufacturing. Memory size of upto 1Mbyte is available. The data rate supported is 212 kbps. The example of this type 3 tag is sony Felica.

Type 4 tag : This tag type is ISO/IEC 14443 (A or/and B) standard compliant. This tag also is pre-configured at the time of manufacturing. This tag also can either be read & rewritable or it can be read only. The memory size max. supported is 32 Kbytes. The data communication speed supported is 106 Kbps. For communication, APDU as per ISO 7816-4 need to be used.

NFC Signalling types

There are three signalling types used in NFC communication technology standard. Any one of these signalling type is used for communication between initiator and target or between reader and tag. The types are NFC-A, NFC-B and NFC-F. Refer NFC-A vs NFC-B vs NFC-F for more which describes difference between these signalling types.

EnOcean

EnOcean is a wireless technology compliant to energy harvesting. It delivers high data rate at low energy consumption. It takes care of multiple simultaneously transmitting devices. More than about 50 manufacturing companies have already created about 200 EnOcean compliant products. It is specified in International Standard ISO/IEC 14543-3-10.

Following table summarizes the key features/specifications of the EnOcean wirelss technology.

EnOcean wireless technology basics in M2M and IoT

The figure depicts typical EnOcean system. As mentioned unlike other wireless systems EnOcean system devices do not require battery for operation. Wireless sensors use motion converters, solar cells and also thermo converters for energy harvesting.

EnOcean wireless technology can be used for various applications which include smart homes, building automation, M2M (Machine to Machine) communication and IoT (Internet of Things).

Moreover with efficient energy management EnOcean transmits information with the use of radio with minimum amount of energy. EnOcean protocol stack is modular and versatile and hence customer applications are easily integrated with it.

Typical EnOcean chip will have energy converter, energy management, sensor, microcontroller, RF transceiver and antenna.

What is EnOcean Technology ?

Introduction: The EnOcean is a wireless technology which does not require battery for its operation. It uses energy harvesting techniques to power its devices and to transmit extremely short data telegram wirelessly. It uses sub 1 GHz frequency bands for its operation and covers distance of about 300 meters (Outdoors) and 30 meters (indoors). The specifications of EnOcean technology is defined in ISO/IEC 14543-3-1X standard. “EnOCean” is a company which is originator of this energy harvesting wireless technology. The company is headquartered in Oberhaching, Germany. EnOcean Alliance is a international consortium with 400 companies worldwide. The alliance develops and promotes EnOcean technology based products and solutions.

EnOcean technology uses solar cells, motion converters and thermo converters for energy harvesting. It uses energy management techniques so that minimum power is used for small amount of data transmission. The EnOcean software stack is modular and versatile which makes interoperability between different manufacturers of the EnOcean sensors and devices.
Following are the technical features of EnOcean wireless technology.
• Operating Frequency : 868 MHz (Europe and China), 315 MHz (Asia), 902 MHz (North America and Canada), 928 MHz (Japan), 2.4 GHz (World Wide for IoT applications).
• Modulation type : ASK, FSK
• Data rate : 125 Kbps (ASK)
• Channel Bandwidth : 280 KHz (For ASK)
• Transmit power : 6 dBm typical at antenna input
• Receiver sensitivity : -97 dBm typical
• Information data type : Frame (Encoded data at physical layer), Telegram (Consists of maximum of 3 subtelegrams), Subtelegram (After decoding process)

Benefits or advantages of EnOcean Technology

Following are the benefits or advantages of EnOcean Technology:
➨EnOcean devices do not require battery. Hence it is maintenance free.
➨It does not require wires as it is wireless technology. Hence it is easy to install which saves both time and money.
➨It uses interoperable protocol. Sensor profiles are well defined and all EnOcean devices are identified by 32 bit unique transmission ID. Hence devices and sensors from different manufacturers can be installed together in the same building or home without any issues.
➨Reduced fire risk and inductive fields.
➨It transmits small size data with minimum power to longer range. For example, 50 µW power is needed to transmit small telegram to about 300 meters in a free field.
➨EnOcean technology co-exist with WLAN, DECT, PMR systems due to no interference between them.
➨Risk of data collision is very low due to use of extremely short telegram (~ 1ms) or data overhead in EnOcean technology.
➨It uses license free radio frequency spectrum below 1 GHz world wide in different bands.
➨Each EnOcean nodes has its own processor. Moreover it uses distributed intelligence so that entire EnOcean system does not fail if a single component or device fails.
➨It covers distance of up to 30 meters in indoors and 300 meters in outdoors (free field) using sub 1GHz frequency bands. It supports range from 10 meters (indoors) to 100 meters (outdoors) using 2.4 GHz band.

Drawbacks or disadvantages of EnOcean Technology

Following are the comparative limitations or drawbacks or disadvantages of EnOcean Technology with respect to other indoor wireless technologies.
➨It offers lower data rate (~ 125 Kbps ) compare to Zigbee (max. 250 Kbps) , Bluetooth (720 Kbps), UWB (110 Mbps) and WLAN (11 to 54 Mbps).
➨It supports medium range (~ 30 meters) indoors which is less compare to Zigbee (~100 m), UWB (~300 m) and Wavenis (~1000 m) technology.
➨It offers basic security using 32 bit unique ID. For applications requiring additional security such as smart homes, maximum 24 bit RC (Rolling Code) is incremented with each telegram and 128 bit AES algorithm is employed.