Making rabbit ears ready for prime time

May 14, 2001  •  Post A Comment

Next-generation receivers have taken center stage in the scramble to rescue digital television from its stalled rollout. But terrestrial broadcasters heavily invested in making DTV work recognize that they need a “modern coat hanger” (indoor antenna) to go with the new receiver-and it has to be something smart, easy, good-looking and cheap enough to draw customers.
“The first-line problem in indoor reception is field strength,” said Andrew Miller, a senior technical staff member of iBlast, a consortium of terrestrial TV stations intent on mining digital signals for datacasting and television fare. “There’s a point where you run into fundamental physics and the signal’s just too damn weak.”
Resolving this dilemma is crucial for iBlast. The 14-month-old consortium is in negotiations but has yet to sign a content deal for its datacasting services as its member stations’ assets dwindle due to skepticism over DTV.
Recent iBlast field tests put digital signal strength at close to 90 percent with a number of prototype antennas (see photos). But the report noted that the tests “were not designed to seek out areas of weakness.” As one employee said, “We didn’t go looking for trouble.”
For at least the next six to eight months, Mr. Miller conceded, the industry will be saddled with “dumb” antennas. Improvements will focus on making them as highly directional as possible, restricting the angle of reception to boost gain (output based on input) and attaching state-of-the-art amplifiers.
The problems with being highly directional, iBlast RF Reception Manager Jerry Glaser said, boil down to cost, overloading the amplifiers and other modulation distortions. Mr. Glaser believes the best solution would be an interface between the antenna and the receiver’s demodulator. This interface would direct the antenna to best find and track the signal and order it not to send back multipath distortions to get the cleanest rendition of what viewers want to see and hear.
Once the turf of the U.S. military, smart antennas show big promise for commercial use as information becomes declassified.
Boylston, Mass.-based MegaWave, a 7-year-old antenna specialist that chiefly works on government contracts, developed an indoor prototype that looks like a Maltese Cross. It’s basically two crossed antennas equipped with a pre-amplifier and voltage running on a coaxial cable to the antenna. The equipment is controlled manually; there’s neither a motor nor movable parts.
The goal is to increase the two-element antenna to six, automate the process and connect the antenna directly to a TV set, which would trigger the optimization process each time it tunes into a new channel. To do this, MegaWave needs a partner to help develop an interface between the antenna and receiver. It has contacted a number of possibilities, including iBlast and Oren Semiconductor, which impressed NAB attendees with its new take on digital receivers.
“If somebody were willing to throw money at it and get it in production, it would probably be out there in a year,” MegaWave President Glynda Benham said.
“They not only have to work, they’ve got to look cool,” said Jim Kutzner, senior technology director at the Advanced Television Technology Center. He believes that sexy antennas would definitely find takers in this market, which is usually seen as about 20 percent of TV viewers.
“Most homes have multiple TV sets-and most of those are not connected to anything but the antennas sitting on top of them,” he said. “With an average of three to four TV sets per home and only one or two connected by cable or DBS, perhaps as many as half are connected to nothing but an antenna. If the system cannot serve those antennas, we have a big problem.”