The National Association of Broadcasters hopes cellular handset and other portable device manufacturers will use new antenna designs it helped fund for radio and ATSC mobile DTV receiver products.
NAB’s technology advancement program FASTROAD has released two reports. They deal with the development of improved VHF and UHF antennas to support FM and mobile DTV reception in handheld devices. (FASTROAD stands for “Flexible Advanced Services for Television & Radio On All Devices.”)
New embedded antenna designs offer a more attractive antenna solution to handheld device manufacturers than the headset cords or fragile, telescoping “monopoles” now in use, NAB believes.
The reports offer results of development efforts by antenna systems company Ethertronics and The Technology Partnership, a technology development firm based in the U.K.
Each came up with antenna solutions to operate over low- and high-VHF and UHF TV band frequencies as well as the VHF frequencies that comprise the FM band, NAB said. This broad frequency range requirement, combined with the size and power constraints of cell phones, presented a “significant challenge” for design and implementation of small antenna systems.
In its report (PDF), San Diego-based TTP said it assessed the feasibility of a single antenna to cover all the bands, and found that most TV tuners have separate VHF and UHF inputs, and do not include analog FM or HD Radio tuners. TTP also found that no single antenna can operate in all the target bands efficiently. “Hence, separate antennas are acceptable for UHF and VHF bands,” it concluded. TTP identified a number of tuner ICs “with a particular focus on the emerging HD Radio and ATSC-M/H technologies.”
The Ethertronics report (PDF) describes developing a prototype embedded antenna and testing it with a demonstration board powered by a battery for powering the module along with a DIP switch and potentiometer to switch bands and tune the antenna response. The board simulated the width and length of a typical handset or smart phone, according to Ethertronics.
The company said its FASTROAD active tunable antenna prototype testing shows the antenna can provide good antenna gain performance across the three designated frequency bands. “The technique of using a single common antenna element and driving it with multiple tuning circuits” is a viable solution for an internal antenna for mobile FM and DTV applications, according to Ethertronics. It estimated the cost for fabricating, assembling and testing each FASTROAD embedded antenna for volume manufacturing in quantities of 200,000 or more at $1.85 per device.
