Special subject for Thursday 1 PM Study Group meeting
Colleagues,
We have made arrangements for having a meeting during the meeting of the
Studygroup Enhanced 802.11 MAC scheduled for 1-3 PM on Thursday, September
16, with a group that is looking for using our standard for their
application. The purpose of this meeting will to see whether the
requirements fall under the Study Group Charter or whether we need to set-up
a new study group for the subject.
Through the activities of 802.15, I received the request to have a meeting
with a group called "Dedicated Short Range Communications". It is one of the
primary communication links in the Intelligent Transportation Systems (ITS)
Architecture. They are looking for an allocation in the 5.825 to 5.925 GHz
band. They are operating under the American Society for Testing and
Materials (ASTM) subcommittee 17.51 DSRC
I have asked their permission to send their Requirements Document to our
group. As soon as I have the permission, I will send a copy to the web.
Below I have attached the Terms of Reference of the group.
Regards
----------
Vic Hayes,
Chair, IEEE P802.11, Standards WG for Wireless Local Area Networks
Lucent Technologies Nederland B.V.
Zadelstede 1-10
3431 JZ Nieuwegein
The Netherlands
voice phone number: +31 30 6097528 (Time Zone UTC+2)
fax phone number: +31 30 609 7556
e-mail: vichayes@lucent.com
DSRC is "Dedicated Short Range Communications" and is one of the
primary communication links in the Intelligent Transportation Systems
(ITS) Architecture.
We are operating under the American Society for Testing and Materials
(ASTM) subcommittee 17.51 DSRC for which Dam Smith is the staff
coordinator. His phone number is 610-832-9727 and his e-mail address is
dsmith@astm.org.
The 5.825 to 5.925 GHz band is currently in the allocation process at
the
FCC. In response to our petition last year and the mandate by congress
to
allocate spectrum to ITS, we expect the allocation of the band for DSRC
operations on a co-primary basis by the end of the year. Band use rule
development and band assignment is expected to take place next year.
This band is exclusive to North America. The rest of the world will
use
different variations of frequencies in the 5.725 to 5.825 GHz ISM band
for
DSRC. However, an ISO standard application layer has just been
approved
for ballot as a committee draft. This standard should enable all DSRC
applications to interface to the different region specific MAC and PHY
layers.
It is of primary importance that North American interoperability be
established in this band, but there are currently many existing MAC and
PHY layers to choose from. Each different MAC gives specific
manufacturers
an advantage. We think it is a good idea to explore the possibility of
using a MAC layer that everyone can use to enable a level playing
field.
Also, the Japanese government would also like Japan and North America
to
use the same standard even if the frequencies are slightly different.
The major issue with the IEEE 802.11 MAC is initialization time and
overhead. The IEEE 802.11 MAC does a wonderful job in the static data
dump
applications that DSRC must implement but has much more overhead than
any
of the other MACs that we could use for high speed operations. The DSRC
protocol must be able to enter the net at speeds up to 120 mph and
enable
the On-Board Equipment (OBE) or STA to start transmission in 1 to 2
msec
after receiving the initial access point frame at the assigned signal
level threshold for the application.
Looking forward to our discussions.
Broady