IEEE Spectrum February, 2009 - 40

trial broadcast signal provides. For videophiles who have already spent a fortune
on their home-theater systems, a couple of
hundred dollars more for a top-of-the-line
antenna obviously makes sense. And of
course, antennas are also good backup for
the times when the cable gets cut or the satellite system fades out due to rain or snow.
In addition, they serve second TV sets in
houses not wired to distribute signals to
every room.
Suddenly the dowdy TV antenna, a
piece of technology that has changed little over the past 30 years, is about to be
the belle of the ball.

winegard
SquareShooter

et's say you've gone and bought a highdefinition LCD TV that's as big as your outstretched arms. And perhaps you've also
splurged on a 7.1 channel surround sound system,
and an upconverting DVD player or maybe a sleek
Blu-ray player. Maybe you've got a state-of-the-art
game console or Apple TV or some other Web-based
feed. Well, come 17 February, you just might want
one more thing: a new antenna on your roof.

If you live in the United States and
you're one of the 19 million people who
still prefer to pull their TV signals out of
the air rather than pay a cable company
to deliver them, you may already know
that this month the vast majority of analog television broadcasts in the United
States are scheduled to end and most free,
over-the-air TV signals will be transmitted only in the new digital Advanced
Television Systems Committee (ATSC)
format. A massive advertising campaign
is now telling people who get their signals from the ether that they'll need a
TV with a built-in ATSC tuner or a digital converter box to display their favorite programs.
What the ads don't mention is that
most of those people will also need a new
46

NA * iEEE SpEctrum * FEbruAry 2009

antenna. For the vast majority of you out
there in Broadcast-TV Land, the quality of
what you see-or even whether you get a
picture at all-will depend not on your TV
or converter box but on the antenna that
brings the signal to them.
If you have a cable or satellite hookup,
you might think that this antenna issue is
irrelevant-but think again. Some owners
of high-end systems complain that the signals coming from their satellite or cable
provider aren't giving them the picture
quality they expected. That's because
cable and satellite operators often use
lossy compression algorithms to squeeze
more channels, particularly local channels, into their allotted bandwidth. This
compression often results in a picture with
less detail than the corresponding terres-

one, however, are the days when
a large rooftop antenna was a status
symbol. Cellphones and handheld
GPS units have conditioned consumers
to expect reliable wireless services in very
small packages. Such dramatic changes in
consumer preferences-coupled with the
new frequency allocations, channel distributions, and high demand for reliable overthe-air digital antennas-mean that the
time for new designs has indeed come.
Most TV viewers think of antennas
as simple devices, but you're tech savvy,
so of course you'd never assume this.
Nevertheless, bear with us briefly as we
review Antennas 101.
The decades-old designs of most TV
antennas on rooftops-and in the market today-are typically configured on a
horizontal fish bone, with arms of varying lengths to handle a broad range of
frequencies.Though the engineering of
antennas in other spheres has advanced
radically over the years, manufacturers
of television equipment have stuck pretty
much with the old designs for economic
reasons. Traditional antennas were good
enough for analog television, and the
shrinking customer base for broadcast
reception didn't offer much incentive to
plow money into new designs.
The transition to digital has changed
all that. Most digital channels are
broadcast in UHF, and UHF antennas
are smaller than those used for analog
TV, where most broadcast signals were
VHF. Also, the multipath problem, arising from signals that reflect off buildings
and hills, which may have occasionally
caused ghosting on analog TVs, can completely destroy a digital picture.
A few designers and manufacturers
have done the necessary research and
development and introduced improved
models. First out of the labs were the
Silver Sensor, introduced by Antiference,
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Table of Contents for the Digital Edition of IEEE Spectrum February, 2009