Wireless Communications
Chapter 6
High Rate Wireless Personal Area
Networks
Wireless# Guide to Wireless Communications 2
Objectives
•
Define a high rate wireless personal area network (HR
WPAN)
•
List the different HR WPAN standards and their
applications
•
Explain how WiMedia and UWB work
•
Outline the issues facing WPAN technologies
•
Describe the security features of each HR WPAN
technology
Wireless# Guide to Wireless Communications 3
High Rate WPAN Standards
•
IEEE is currently working on two standards
–
IEEE 802.15.3 and 802.15.5
•
IEEE 802.15.3 standard
–
Defines the specifications for HR WPANs supporting
speeds of 11, 22, 33, and up to 55 Mbps
•

–
Require quality-of-service (QOS) capabilities
–
Connections should be simple and automatic
–
Devices should be able to connect to multiple other
devices
–
Security features should be included
Wireless# Guide to Wireless Communications 6
WiMedia Protocol Stack
•
WiMedia group defined two different architectures
–
For the upper layers of the protocol stack
–
One is used for multimedia audio/visual applications
and the other for data transfer applications
•
The lower two layers of the stack (MAC and PHY)
–
Are implemented in hardware
•
802.15.3 PHY layer
–
Converts data bits into a modulated RF signal
–
802.15.3 standard uses the ISM 2.4 GHz band
Wireless# Guide to Wireless Communications 7
WiMedia Protocol Stack (continued)

See Table 6-2 for modulation techniques
–
Enhancements
•
Passive scanning
•
Dynamic channel selection
•
Ability to request channel quality information
•
Link quality and received signal strength indication
•
Transmit power control
•
An 802.11 coexistence channel plan
•
Lower transmit power
•
Neighbor piconet capability
Wireless# Guide to Wireless Communications 11
WiMedia Protocol Stack (continued)
Wireless# Guide to Wireless Communications 12
802.15.3 Network Topology
•
Piconet coordinator (PNC)
–
Role assumed by the first device in the area
–
Provides all of the basic communications timing in a
piconet

•
The IEEE 802.15.3 MAC layer functionality
–
Connection time (association) is fast
–
Devices associated with the piconet can use a short,
one-octet device ID
–
Devices can obtain information about the capabilities of
other devices
–
Peer-to-peer (ad hoc) networking
–
Data transport with QoS
–
Security
–
Efficient data transfer using superframes
Wireless# Guide to Wireless Communications 18
Additional MAC Layer Functionality
(continued)