Continue reading Buckeyes embed antennas in clothes, couture to improve radio reception?
Buckeyes embed antennas in clothes, couture to improve radio reception? originally appeared on Engadget on Tue, 23 Aug 2011 12:12:00 EDT. Please see our terms for use of feeds.
Permalink | | Email this | CommentsDr. Eric Walton of the ElectroScience Laboratory at The Ohio State University has developed a way to connect an on-glass antenna to a transmission cable that overcomes impedance matching problems in the AM and FM bands. Impedance matching for on-glass antennas is a challenge since in the FM frequency band coaxial cable impedance is often 50 ohms, and in the much lower AM frequency band the antenna and the receiver input impedance is much closer to 6,000 ohms. This invention results in a wide bandwidth and a transformation from the coaxial cable impedance to the antenna impedance. The matching circuit is especially designed to be imbedded in a small window attachment clip. This invention would be particularly suited for use in automobiles where the rear window heater grid can also function as an antenna, and consequently is essential along with another of Dr. Walton’s inventions which is described in U.S. Patent #5,781,160 (OSU Reference #94048). It should be noted, however, that this method is applicable in other on-glass wideband antenna configurations where impedance matching in the AM and FM bands must be achieved.
Dr. Eric Walton of the ElectroScience Laboratory at The Ohio State University has developed an automotive antenna that is effectively incorporated into the resistive, conductive heating elements found in automotive windows. The automobile industry has long recognized the advantages of forming an antenna in a vehicle window by imbedding conductors in the window glass. Manufacturers have also recognized that such windows can be defogged or defrosted by distributing resistive conductors over a major portion of the window area (the familiar heater grid found on the rear window of automobiles). It has been realized that the same conductors may be used for both heating the window area and as the communications antenna. The challenge lies in that the heater power source must be isolated from radio frequency signals in order to prevent RF currents from being shorted through the vehicle or heater power system. Previous attempts at isolation have been successful but have resulted in the need for heavy, expensive components and the need for separate antennas for different frequency bands. Dr. Walton’s design allows for optimal AM/FM reception (or the reception of other relatively low and high frequency bands found in modern wireless communication) and impedance matching using a single antenna, whereas previous designs required the use of two separate, different antennas. The design further allows for an apparatus with reduced size, weight, and cost as compared to previous methods. When coupled with U.S. Patents #6,320,558 and #6,483,468 (On-Glass Impedance Matching Antenna Connector, Reference #99062), impedance matching in the AM and FM bands can be easily achieved and a complete on-glass automotive AM/FM antenna/heater grid configuration realized.
Researchers at the ElectroScience Laboratory at The Ohio State University, in cooperation with an Italian automotive antenna manufacturer, have developed an improved wire pattern layout for an automotive window antenna. Automobiles traditionally have heating elements printed on the rear window for defrosting/defogging purposes, and such elements usually cover the majority of the window in order to defrost the entire area. This leaves little room for an isolated RF antenna on the window, and as a result the smaller antenna geometry results in relatively poor performance. This invention alleviates this problem by incorporating the RF antenna into the heater grid configuration, while taking into account the effects of the heater grid pattern and the general characteristics of RF current throughout the circuit. The result is a rear window antenna with improved performance that is seamlessly and attractively integrated into the already existing heater grid configuration.
Dr. Eric Walton of the ElectroScience Laboratory at The Ohio State University has developed a unique metallic panel aperture design that allows the transmission of radio waves through the panel while blocking infrared radiation. Optically transparent metal panels are often used in automotive or building windows where heating and/or the reflection of infrared radiation is desired. It has been shown that a thin, transparent metallic layer can be deposited on one of the layers of a multi-layer automotive windshield and used for heating/deicing/defogging when powered using bus bars on the top and bottom of the windshield. However, a uniform metallic coating prevents the transmission of radio signals, which is unacceptable given the widespread use of cell phones, GPS receivers, and other electronics commonly used in automobiles and buildings. This invention alleviates these problems; permitting uniform heat distribution and simultaneously allowing the passage of radio waves. The invention is useful in any application where a metallic panel is used to heat a material or to reflect infrared radiation, and where heat uniformity and radio transmission is important.