It’s Monday morning, 5:00 am in Houston, Texas,
and the majority of Houstonians are still sound asleep. Light rain showers are forecast
for the morning and patchy fog lingers throughout the Houston area. Already an
eighteen-wheeler full of fuel has jackknifed on the city’s East side and a four-car
pileup on the Southwest freeway has caused traffic to be diverted to the access road.
Shadow Broadcast Services producer Lyndon Joslin settles down in front of his computer,
the primary link to eighteen affiliate stations, and gets ready for what promises to be a
long morning.
Most folks probably dream of doing something less stressful when they retire; fishing,
refinishing furniture and playing with the grandchildren. Lyndon is probably no different
than anyone else, longing for the days of a less stressful existence. Something like air
traffic controller at LAX, working the bomb squad in Northern Ireland, or perhaps fighting
oil well fires in the desert. One thing’s for certain—he’d have to look
long and hard to find a job more demanding!
Two scanners, a two-way radio, a telephone that rings incessantly, and even a closed
circuit television camera atop their office building provide a steady flow of data, all
making its way to the producer. His job is to assimilate this tidal wave of disjointed
data and condense it down to one screen of meaningful information. This information is
then sent to all eighteen affiliate radio and TV stations via modem at a rate of once
every two minutes.
So where does all this information come from and how does it get out to the stations so
quickly? To find out, let’s take a look at what goes on behind the scenes of a
traffic reporting operation in one of the nation’s largest metropolitan regions.
Shadow Broadcast Services maintains offices at eight metropolitan areas around the nation.
At the Houston office is an impressive variety of high-tech tools that feed information
from various sources directly to their studio. However, Shadow’s chief source of
information is the mobile traffic reporters. It’s the reporter’s job to get to
the scene as soon as possible and give a first-hand account of the delay, along with an
estimate of when traffic should again be flowing.
The number of reporters varies throughout the day, but there are typically four that
patrol the freeways by car and two who travel in aircraft. Needless to say, getting around
Houston’s eighteen hundred square miles is a lot quicker at 130 miles per hour. When
the cloud ceiling is above 1,200 feet, the two airborne reporters each travel in a Cessna
172. When the ceiling are lower than 1,200 feet, the Cessna’s cannot fly due to FAA
regulations and two Bell Jet Ranger helicopters are used instead.
When a major problem does occur, the traffic reporters will often suggest alternate
routes. Information regarding the viability of the alternates is usually verified by one
of the aircraft to ensure that the alternate is not already backed up from other’s
fleeing the original problem. Armed with this information, motorists can then decide if
they want to take alternate routes around the delay or just sit it out.
In addition to dispatching reporters to where accidents have occurred, reporters are sent
to areas where conditions are ripe for problems to develop. Since Houston is so large,
there can be a violent storm on one side and clear weather on the other. Shadow closely
monitors changing weather conditions with a NOAA weather receiver and a Doppler radar
satellite downlink directly to the studio. Then, when inclement weather moves into the
area, reporters can already be in place to keep track of the traffic.
The reporters in the field stay in touch with the studio via conventional UHF radios
through a repeater. The producer uses the two-way to obtain driving conditions from the
field and to dispatch reporters to any situations that the he may become aware of from
another source. Many of the reporters also carry scanners so they can quickly start moving
toward a scene as soon as they hear emergency services being dispatched.
Reports from the field may be transmitted back to the Shadow studio by one of two
different types of radios. For those affiliate stations who prefer a higher quality audio
report from the field (usually from the airborne reporters), Marti FM wide-band
transmitters are used. Other affiliates may prefer the sound of the standard FM
narrow-band radios because of the perceived sense of realism. The reports from the field
are recorded on tape cartridge, then transmitted selected affiliate stations via phone
line.
For local radio station KTRH, live broadcasts are periodically produced at the Shadow
studio. The link from Shadow to KTRH is accomplished via a wideband (eight kilohertz)
dedicated phone line, so voice audio quality is remarkably good. As the announcer at
Shadow makes his report, he can listen to the producer at the affiliate station in his
headphones over a conventional phone line referred to as a “haulback.”
Traffic reporting has been typically geared to radio, for obvious reasons. However, many
television stations have discovered that viewers may want to check the traffic situation
before venturing out, and now include traffic reports as part of the news. To fill this
need, Shadow provides traffic information with computer generated graphics to local
television stations. Since Shadow already has the traffic details available, it’s
just a matter of updating a graphic depiction map of Houston on an Amiga computer. The
images are then transmitted to the TV stations via microwave link.
Keeping Texas on the Move
In the early eighties, Houston was experiencing one of the largest growth spurts ever.
With the oil industry booming in Texas and the auto industry on the decline up North, the
population was growing by leaps and bounds. Too many cars on a freeway system already at
near-capacity created unprecedented traffic jams. Realizing that something had to be done
soon, the Texas Department of Transportation began a program of accelerated freeway
renovation. However, it has only been in recent years that the really high-tech hardware
came on the scene.
In order to help alleviate the congestions, the Texas Department of Transportation (DOT)
established the Traffic Management Center. Under the direction of Mr. Carlton Allen, the
latest in traffic monitoring and flow control technology is being implemented.
At the Operations Center, data is gathered with fifty-three high-resolution closed-circuit
cameras placed at strategic locations along Houston’s busiest freeways. From the
Center, the operators can control the pan, tilt and zoom of each camera. The signal is
transmitted from the cameras to the Center via fiber optics, and the resolution of the
picture is nothing less than incredible. To demonstrate, Mr. Allen zoomed in on a distant
street sign with lettering approximately 3” high. Even from its lofty perch high
above the freeway, the name of the street was easily discernible. With the help of the
cameras, the operators can quickly pinpoint problems along the freeway system and the
appropriate emergency services can be dispatched in a matter of minutes.
Houston’s traffic woes are by no means limited to the freeways. At the Astrodome,
events like football games, rodeos or concerts may draw a crowd of over 60,000. For such
events, Metro buses using the “park and ride” concept are often utilized to
alleviate the congestion. To ensure that the buses keep moving, an array of ten
closed-circuit cameras monitor traffic around the Astrodome. Coordinators stationed at the
Traffic Management Center are then able to guide the buses and other event traffic to and
from the dome via the least congested route.
For those motorists who frequently travel Houston’s toll roads, an electronic device
called the EZ Tag may be leased to expedite the trip through the toll booth. The EZ Tag is
a small transponder, about the size of a pack of cigarettes, only half as thick, which
attaches to the windshield. Whenever the motorist drives through a toll gate, the EZ Tag
is interrogated automatically and the appropriate account is debited for the toll.
By taking advantage of the EZ Tag transponders, the Texas DOT has implemented another
piece of impressive traffic-tracking technology. At 135 freeway locations around Houston,
the EZ Tags are interrogated as they drive past a reader, usually mounted on an overhead
traffic sign. Computer tracking of the vehicle is begun as it passes the first reader and
is updated as it passes subsequent readers. Back at the Center, the average speed for
those vehicles with an EZ Tag is computed and graphically depicted on a Houston freeway
map. By glancing at the thirty-five inch Mitsubishi monitor, the average speed for a given
segment of a freeway can quickly be determined.
The only problem with the system, admitted Mr. Allen, is at off-peak when there is
sometimes not enough traffic with EZ Tags to keep the system updated with real-time
information. However, with over thirty-eight thousand EZ Tags in use, and more being
issued every day, the quality of data from this system should only become better and more
reliable.
Another innovative program, a joint effort of the Texas DOT and Metro, is the Motorist
Assistance Program (MAP). Nine MAP vans, which are manned by Harris county sheriff’s
deputies, patrol the freeways from six in the morning until ten at night, five days a week
(excluding holidays).
The ultimate objective of the Motorist Assistance Program is to improve mobility and keep
traffic flowing on the freeway system by rendering aid to stranded motorists. One duty the
officers are not charged with is traffic enforcement. To a motorist stranded on the
freeway, this is one time they’ll be glad to see flashing lights in the mirror!
Motorists can summon assistance by dialing “CALL MAP” (225-5627) or by placing a
toll-free call (*627) from their cellular phone. The MAP vans are dispatched and report
problems back to the Traffic Management Center using the county’s 800 MHz trunked
system.
Gathering all of this information is great, but how does it make it out to the motorists
trying to get across town? Various media, including Shadow, are allowed to station
reporters at the Traffic Management Center during peak traffic periods. There is then a
two-way sharing of information between personnel at the Center and the traffic reporters.
So in essence, the Traffic Management Center becomes a clearing house for traffic
information in the Houston area. The Texas DOT also keeps motorists apprised of traffic
conditions with changeable traffic information signs which are updated from the Center via
phone line.
Scanning Traffic Reporters In Your Area
The list of frequencies in the footnote should be of interest to those who live in
Houston. However, if you live in another region of the country, the following tips should
be helpful in finding the traffic reporters in your area.
Traffic reporting is usually done on frequencies allocated for remote media broadcasts. On
the VHF band, search between 161.640 and 161.760 MHz. On the UHF band, the repeater output
is usually between 450 and 451 MHz. The input frequency to the repeater is five megahertz
up, between 455 and 456 MHz. Also, it is not unusual for simplex transmissions to be
conducted on the repeater input frequencies, especially remote-to-base traffic reports
used to feed the affiliate stations.
As you search these frequency ranges for activity, you may find a lot more than just
traffic reports. There is usually an abundance of interesting activity here if you live in
an area where radio or television broadcasts originate. I strongly suggest you locate and
log the frequencies for future use. Then, in the event of a disaster in your area, you
will have the unedited news long before it reaches the general public.
Though broadcast services such as Shadow are usually better equipped to provide quality
traffic information, some radio and television stations prefer to do their own traffic
reporting and production. Often the larger stations which already have aircraft for their
news services may opt to customize the traffic reports for their own format. Again, look
for these services in the same frequency ranges.
When listening to the various traffic reporting agencies, you’ll usually hear more
than just mobile reporters posting traffic conditions. Often you will hear the studio
feeds as a mobile reporter broadcasts overall traffic conditions for the region. So by
monitoring these reports with your scanner, you’ll have crucial traffic information
long before it reaches the general public!
All articles are property of Haskell L.
Moore, and may not be reproduced
in whole or in part without written permission from the author.
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