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WiMAX's Role in Untangling Traffic Problems
As bandwidth needs and cost of wired connectivity soar, cities are turning to WiMAX to cost-effectively connect traffic lights and cameras to relieve congestion and enforce traffic laws.
We've all seen the cameras at busy intersections, looming atop the traffic
lights, ready to catch us if we dare to run a red light. These cameras are part
of the now well-known "Red Light Running" program, where sensors detect red
light violators and quickly snap a photo of both the license plate number and
the driver. While nobody seems to appreciate the program when they receive their
ticket in the mail, the program definitely works - some cities have seen as much
as a 90 percent
decrease in red light running-related accidents.
Until recent years, the only realistic option for connecting the cameras at
these intersections was to run a dedicated leased line to each camera at every
intersection a city wished to deploy. This was not only an extremely costly
solution, with leased lines running as much as $2,000 (in some cases more) per
month, but installing a new dedicated wired line for each camera also required a
great deal of labor, further driving up the cost and impeding the scalability of
these systems.
Today, however, cities and counties are turning to WiMAX technologies to remove
the cost and complexity roadblocks that have prevented greater rollout of these
programs. WiMAX, originally designed as a backhaul technology, has proven ideal
for the increased bandwidths required by HD video cameras. And since today's
wireless radios can not only backhaul the traffic from multiple cameras while
(in some cases) powering co-located cameras directly from the radio via Power
over Ethernet (PoE), WiMAX and other high-bandwidth point-to-multipoint
technologies are ideally suited to drive down the cost of traffic camera
connectivity while greatly easing deployments.
Often times, Red Light Running is the first traffic program initiated after a
camera deployment because the program not only provides a strong reduction in
traffic incidents in a short period of time - but also because it provides an
immediate revenue stream. At first, before drivers notice where the cameras are
deployed, the revenue from traffic ticketing increases dramatically. That
revenue often offsets part of the initial cost of the deployment for the
city/county. Over time, that revenue decreases as people learn to be more
careful at intersections, but that is when the more important return on
investment indicator - the reduction of fatal accidents - becomes the focus.
The utility of WiMAX for traffic applications does not end with the Red Light
Running program, though. Now that WiMAX has reduced both the time and the cost
associated with deploying cameras, resulting in thousands of intersections being
unwired in cities across the globe, some have identified other ways that they
can utilize the wireless networks they have put in place to yield even more
traffic benefits. In particular, the trend of traffic synchronization and
management has emerged as a leading trend.
Traffic synchronization refers to the connection and networking of many
intersections in a particular area so that the city can control those
intersections during hours of heavy commute hours to increase the flow of
traffic and reduce congestion. By utilizing cameras placed at every intersection
and special traffic management software, these traffic synchronization networks
can monitor the flow of traffic and determine when an area is congested, then
adjust the timing of the lights to increase traffic flow in the direction that
is most congested. The combination of traffic sensors that communicate with the
traffic management software and the visual confirmation provided to the traffic
control centers via the networked cameras give traffic operators the ability to
make the changes necessary at any given time (as opposed to relying purely on
timed lights) to ensure that traffic continues to move smoothly.
One example of a large traffic synchronization network that is utilizing WiMAX
technology is the County of Los Angeles. LA County is one of the most congested
traffic areas in the world, and to combat the problem, the County decided to
deploy a wireless traffic synchronization network running over unlicensed WiMAX.
To date, the County has over 1,200 intersections deployed, with WiMAX radios
connecting not only the lights, but the video cameras at those intersections as
well.
The main culprit for LA County's traffic problems is rush-hour traffic, so the
wireless traffic synchronization network provides the flexibility needed to
dynamically change the lights as needed - providing longer green lights for
inbound or outbound traffic, depending on the time of day. And because of this
flexibility, the system also enables traffic operators to react and help control
traffic caused by emergencies or accidents. Based on the initial deployment, LA
County has determined that the wireless traffic synchronization network has
reduced commute times in the deployed areas by nearly 20 percent - a huge
improvement in such a congested area.
Another example is the town of Umatilla, Oregon. While Umatilla does not suffer
from the same traffic congestion problems that LA County faces, it decided to
deploy a wireless traffic synchronization network for a completely different
reason. You see, one of the major industries in the town of Umatilla is a large
chemical weapons depot. As part of the town's extensive emergency preparation
planning - should anything ever go wrong at the depot - they implemented the
traffic synchronization system so that they could enable everyone to get out of
town quickly in the case of an emergency. If something was to happen, they could
turn all inbound lights red, and ensure that all the roads leading out of the
city had green lights - enabling everyone to evacuate quickly and smoothly.
There are many more examples, all of which suggest that wireless traffic
synchronization is a growing trend. And following on the heels of other traffic
oriented uses of wireless technology (such as speed and Red Light Running
enforcement), the utility of traffic synchronization is just the next evolution
of wireless traffic management systems. Surely that evolution will continue as
the traffic management systems become more and more complex, which will only
increase the need for cost-effective, easy to deploy and flexible wireless
solutions to connect and backhaul these systems.
WiMAX and other high-bandwidth wireless systems are ideal for these deployments,
because they decrease the initial cost of deployment for traffic systems and
other outdoor applications (download
a free copy of the recent Farpoint Group analyst white paper on the TCO of
Wireless vs. Wired for Outdoor Applications for more cost analysis). In
addition, these high-bandwidth wireless networks increase the amount of
applications that can be run over these systems, increasing the ROI. That blend
of decreased up front deployment cost, increased utility (Red Light Running,
traffic synchronization, speed enforcement, etc.) and accelerated ROI is a
winning combination when applying for grants or securing funding for your
traffic network.
Robb Henshaw is the Director of Marketing & Communications at
Proxim Wireless, a manufacturer of end-to-end broadband wireless systems, where he
oversees the company's global marketing and communications efforts. For the last
8 years he has been dedicated to helping develop the wireless industry, with
expertise in technologies ranging from enterprise WLANs, to carrier-grade
wireless backhaul, to WiMAX and point-to-multipoint broadband wireless access (BWA)
solutions.
