1. Wireless Personal Area Networks
Chapter 15

2. WPAN and Wireless Networks
WWAN (3G,4G?)
WMAN (WiMax)
Low throughput, Long range
WLAN (Wi-Fi)
High throughput, short range
WPAN
Low throughput, short range

3. Topics discussed in this section:
Wireless Personal Area Networks
A WPAN (wireless personal area network) is a personal area network - a network for interconnecting devices centered around an individual person's workspace - in which the connections are wireless. WPAN uses some technology that permits communications in a very short range (10 – 100 m).
Topics discussed in this section:
Used Technologies IEEE Standards

4. Unlicensed Spectrum for Wireless Networks
Wireless Personal Area Networks
Unlicensed Spectrum for Wireless Networks
ISM – Industrial, Scientific and Medical band)
The only ISM band guaranteed to be available in every country is the one at 2.4GHz (2.4–2.483 GHz).
Free for anyone to use for almost any purpose.
Employed by most wireless technologies, many cordless phones and Bluetooth.

5. Wireless Personal Area Networks
WPAN Technologies
Bluetooth
IrDA (Infrared)
Zigbee
UWB (Ultra Wideband )
RFID
NFC

6. Wireless Personal Area Networks
Bluetooth History
1998 – Its primary purpose is to be a wire replacement technology in order to transfer voice and data.
1999 – Bluetooth 1.0 specification is introduced.
2003 – Bluetooth 1.2 Core Specification
2004 – Bluetooth 2.0 Core Specification + EDR (Enhanced Data Rate).
2009 – Bluetooth 3.0 Core Specification + HS (High Speed).

7. Wireless Personal Area Networks
Bluetooth Technology
BT is a short-range wireless radio technology that allows electronic devices to connect to one another.
BT ranges: 10 m, or 100 m.
Its popularity increases as consumers always look for BT to be included in all products they buy.

8. Bluetooth Specifications
Wireless Personal Area Networks
Bluetooth Specifications
Bluetooth devices in a piconet share a common communication channel, its capacity 1 Mbps (3 Mbps or more in newer versions).
The frequency range is 2.4 GHz to GHz.
A piconet has a master and up to seven slaves.

9. PDAs & Handheld Devices
Wireless Personal Area Networks
Bluetooth Applications
PDAs & Handheld Devices
Modems
PC Accessories
(PC Dognles, Printers, Serial Cable, Keyboard, Mouse)
Personal Computers
(Notebook, Desktop, Tablet PC)
Headset/Hands-free
(Automotive Applications)
Mobile
Phones
Consumer Devices
PAN Access Points

10. Wireless Personal Area Networks
Bluetooth Applications
Keyboard, file transfer, handsfree (and headset), etc…

11. Wireless Personal Area Networks
Bluetooth Applications
Activity
Body weight
Peak flow
Blood analysis
Glucose
Oxygen saturation
EMG
Temperature
Heartbeats
Coagulation
ECG
Blood pressure

12. Wireless Personal Area Networks
Bluetooth Advantages
Bluetooth devices are wireless.
BT is inexpensive.
Bluetooth is Automatic.
Standardized Protocol = Interoperability
Low Interferences .
Low energy Consumption.
Share voice and data.

13. Wireless Personal Area Networks
Infrared
Infrared communication is achieved using transmitters/Receivers (transceivers) that modulate noncoherent infrared light.
Transceivers must be within the line of sight of each other either directly or via reflection.
Infrared does not penetrate walls (+ advantages security, and no interference problems).
No license required thus no frequency allocation issue.

14. Infrared Transmission Techniques
Wireless Personal Area Networks
Infrared Transmission Techniques
Three transmission techniques:
1 – Directed Beam Infrared (point-to-point link).
2 – Ominidirectional (single base station that is within line of sight of all other stations (typically, this station is mounted on the ceiling). The base station acts as a multiport repeater.
3 – Diffused (all of the IR transmitters are focused and aimed at a point on a diffusely reflecting ceiling. IR radiation striking the ceiling is reradiated ominidirectional and picked up by all of the receivers in the area.

15. Wireless Personal Area Networks
Infrared Waves
Infrared waves:
with frequencies from 300 GHz to 400 THz
(wavelengths from 1mm to 770 nm).
We cannot use infrared outside a building because the sun’s rays contain infrared waves that can interfere with the communication.

16. Infrared Applications
Wireless Personal Area Networks
Infrared Applications
- The Infrared band, almost 400 THz. It can be used to transmit digital data with a very high data rate.
- The Infrared Data Association (IrDA) sponsors the use of infrared waves by setting standard for using these signals for communication between devices such as keyboards, mice, PCs, and printers.
- IrDA port may be present in a device
- The standard originally defines a data rate of 75 Kbps for a distance up to 8m. The recent standard defines a data rate of 4 Mbps.
- IrDA transmit through line of sight.

17. Wireless Personal Area Networks
ZigBee Technology
ZigBee is a standard for embedded application software that has been approved in late 2004 under wireless networking standards.
ZigBee IEEE is an established set of specifications for wireless personal area networking (WPAN).
ZigBee addresses remote monitoring and controlling applications.
Reference:

18. Wireless Personal Area Networks
ZigBee Features
1 – Low power consumption (ranging from months up to years on standard batteries ).
2- Maximum data rate GHz, MHz, and MHz .
3 – Needed for only two major modes (Tx/Rx or Sleep).
4 – High density of nodes per network.
5 – Low cost.
6 – Simple implementation.
7 – high reliability and Adequate security.
8 – Acceptable Latency (10 ms for PC, 100 ms for

19. IEEE 802.15.4 / ZigBee Stack Architecture
Wireless Personal Area Networks
IEEE / ZigBee Stack Architecture

20. Wireless Personal Area Networks
1 - Network and Application Support layer
- APS sub-layer responsible for maintaining tables that enable matching between two devices and communication among them, discovery, identify other devices that operate in the operating space of any device.
- ZigBee define object is responsible of determining the nature of the device (Coordinator / FFD or RFD) in the network, commencing and replying to binding requests and ensuring a secure relationship between devices.
- The user-defined application refers to the end device that conforms to the ZigBee Standard.

21. Wireless Personal Area Networks
2 - Media access control (MAC) layer
- permits use of several topologies without introducing complexity and is meant to work with large numbers of devices.
3 – Physical (PHY) layer
- accommodates high levels of integration
- enable cheaper implementations

22. Wireless Personal Area Networks
ZigBee Devices
1 – ZigBee Coordinator node (only one, act as a router to other networks, it is designed to store information about the network).
2 – The Full Function Device (intermediary router transmitting data from other devices).
3 – The Reduced Function Device (it is just capable to talk in the network).

23. Wireless Personal Area Networks
ZigBee Applications
Embedded in consumer electronics.
Home and building automation and security systems.
Industrial controls.
PC peripherals.
Medical and industrial sensor applications.
Toys and games and similar applications.

24. Wireless Personal Area Networks
Comparison of Bluetooth and ZigBee
Bluetooth
ZigBee
Transmission Scheme
FHSS (Frequency Hopping Spread Spectrum)
DHSS (Direct Sequence Spread Spectrum)
Modulation
GFSK (Gaussian Frequency Shift Keying)
QPSK (Quadrature Phase Shift Keying) or BPSK (Binary Phase Shift Keying)
Frequency Band
2.4 GHz
2.4 GHz, 915 MHz, 868 MHz
Raw Data Bit Rate
1 Mbps
250 Kbps, 40 Kbps, or 20 Kbps (depends on frequency band)
Power Output
Maximum 100 mW, 2.5 mW, or 1 mW, depending on class
Maximum capability 0.5 mW; maximum as allowed by local regulations
Network Topology
Master-Slave
8 active nodes
Star or Peer-Peer
255 active nodes

25. Ultra wideband Specifications
Wireless Personal Area Networks
Ultra wideband Specifications
Ultra Wideband enables movement of massive files at high data rates over short distance.
High Data Rate (200Mbps within 10m).
Extremely low transmission energy ( less than 1mW).
Low cost.
Extremely difficult to intercept

26. UWB

27. UWB Applications

28. Ultra wideband Applications
Wireless Personal Area Networks
Ultra wideband Applications
Short-distance applications (PC Peripherals).
short-range indoor application
applications with high data rate requirement (Wireless Monitors, Camcorders & Wireless Printing).

29. Wireless Personal Area Networks
RFID Technology
RFID – Radio Frequency Identification
- The concept is that a query is sent out over a radio wave and a subsequent reply is received.
- Its used in supply chain management (just-in-time inventory, reducing theft and fraud, and improving the type and quantity of product marketing information).
- its also used in tracking systems.
- It was invented in 1948 and in commercial applications since 1980.

30. Wireless Personal Area Networks
RFID Technology
RFID components:
- Tag (Passive tag, Active tag).
- Reader with antenna (Fixed or mobile)
- Communications protocol suite.
- Communications network
- Database.
Reference:

31. Wireless Personal Area Networks
RFID Technology
Tag (Passive tag, Active tag):
- Tags can be either Class o (Read only) or Class 1 (Read/Write).
- Reader (or the active tag) initiates the communication via a radio signal to enable the tag to answer with a return radio signal carrying information regarding the item.
- Electronic Product Code (EPC) is used to uniquely identified an item.
- In the future there will be more information tracked via EPC by using EPC Information Services (EPCIS).

32. Example of transmitted information:
Wireless Personal Area Networks
Example of transmitted information:
Current:
- This is where I originated: “manufacturing source”
- This is what I am “a specific pallet carrying boxes of paper towels” or
- This is what I am “a specific box of paper towels”
Future:
- This is my rout tracking: “my mode of transportation, my origination point, my arrival and departure time and location of every stop along the way, and the time I arrived at this final destination point”
- This is my purchase and restocking information: “I was purchased by so and so, on this date and at this price, and now I have left the building – please restock this item”

33. Wireless Personal Area Networks
RFID Technology
Reader with antenna:
- Reader has a distance range to query tag’s information.
- Readers vary in their capabilities such as how many tags a reader can capture within a specific time period, filtering and communicating with a product database.
- Number of readers and their placement in the physical facility is a challenge.

34. Wireless Personal Area Networks
RFID Technology
Communications protocol suite :
- Physical Layer (describes the specific radio frequencies and whether tags and reader are communicating in half or full duplex mode).
- On data-link layer Slotted Aloha scheme is used.
- Application Level Events (ALE) standard defined to support collection of event data coming from readers.
- Reader Protocol (RP) standard is defined to specify how readers capture and communicate event data from tags.
- Communications between readers and in-house database are up to individual implementations.

35. RFID Basic Operation Antenna Tag on Item, box or pallet Computer
1. Tag enters RF field of Reader
2. RF signal powers Tag
3. Tag transmits ID, plus data
4. Reader captures data
5. Reader sends data to computer
6. Computer send data to reader
7. Reader transmits data to tag
Antenna
Tag on
Item, box or
pallet
Computer
Reader

36. Wireless Personal Area Networks
Electric
Waves
Radio
Infra-red
Visible
Light
Ultra-
Violet
X-Rays
Gamma
Rays
Cosmic
9kHz
30kHz
300kHz
3000kHz
30MHz
300MHz
3000MHz
30GHz
300GHz
3000GHz
VLF LF MF HF
VHF
UHF
SHF
EHF
Not
designated
Long
Wave
Medium
Short
Very Low Frequency
Very High Frequency
Low Frequency
Ultra High Frequency
Medium Frequency
Super High Frequency
High Frequency
Extremely High Frequency
Radio Spectrum
kHz
13,56 Mhz
MHz
2,45 and 5,8 GHz
The “RFID” Frequencies
Electromagnetic Spectrum

37. Wireless Personal Area Networks
NFC Technology
NFC – Near Field Communications
- NFC is a set of standards for smart-phones or whatever to establish communication with each other by bringing them into close together (0-5 centimetres).
- NFC operates at MHz
- NFC rates ranging from 106 Kbps – 424 Kbps.
- NFC involves an initiator and a target.

38. Wireless Personal Area Networks
NFC Technology
There are two NFC operational modes:
1- Passive communication mode: The initiator device provides a carrier fields and the target device answers by modulating the existing field.
2- Active communication mode: Both initiator and target device communicate by alternately generating their own fields.

39. Wireless Personal Area Networks
NFC Technology
NFC & other wireless technologies

40. Wireless Personal Area Networks
NFC Technology
NFC use examples:
Paying by mobile devices like cell phones
Credit card integration into a mobile device
Electronic ticketing for transport usage
Personal electronic document
Download of data from kiosks such as railway time table
Flight  and hotel booking
Music and photos download from camera, cell phones, multimedia readers
Connections P2P (peer to peer) for an easy information transmission between wireless devices.