communication & protocols -...
Post on 07-Feb-2018
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www.Ko-FAS.de
Project Ko-TAGProject Ko-TAG
Communication & ProtocolsCommunication & Protocols
The Ko-TAG communication protocol
Network Simulation
Registration
• Observation of the management channel
• Reply to registration requests of the TAGs
• Assignment of addresses and time slots
TOF (Distance Measurement)
• Transmission of Beacons
• Time-Of-Flight Measurements for each
TAG in its time slot
• Duration of a time slot < 15µs
AOA (Angle Measurement)/Data
• Transmission of a Request-Beacon
• Transmission of the replies by the addressed
TAGs
• Angle Measurement of the arrived signal
The Ko-TAG communication protocol is based on three non-overlapping channels used for management
operations, distance measurements, data transmissions and angle estimations. An overlapping star
topology was chosen with a single localization unit (LU) as the center of each star.
The network management runs completely autonomously. No interaction from outside is required.
A specific communication protocol was developed to
answer the specific user requirements.
During communication each LU performs three different
subsequent steps:
The communication frames in the data
and in the management channels are
derived from the 802.11p-Specification.
For Time-Of-Flight Measurements use
short bursts to increase the update
rate.
Packet collision probability can be
significantly reduced with a time slotted
channel access mechanisms within the
own network.
ALL 10
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166H
z
165H
z
165H
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166H
z
165H
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165H
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OBU: Frequency of successfull requests per device
OBU-Nr.
Fre
quency o
f successfu
l re
quests
per
devic
e (
Hz)
ToF
AoA
Data
Verification was performed using the OPNET®
Modeler simulator for wireless networks.
The picture shows an example measurement of the
maximum time required until a distance measurement
has been performed for all TAGs. The corresponding test
setup used 500 TAGs and 75 time slots per cycle.
The single curves represent the behavior regarding a
different dwell time of the devices in the management
channel.
In this scenario a simultaneous registration of all devices
in the network is simulated.
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