Microwave antennas are constructed today by using multilayer circuit board technology. These antennas can be inserted into garments only with difficulty and the resulting garment is uncomfortable to wear. Also, since the antenna is added during the garment manufacture, the cost is increased.
There is prior art in the area of fabric antennas. Van Heerden et al. in U.S. Pat. No. 6,677,917 describes a fabric antenna that consists of a radio frequency transponder and a radio frequency circuit enclosed in a housing and this is attached to conductive thread, glue and substrate. The antenna is enclosed in a seam of the garment. Van Heerden, in U.S. Pat. No. 6,686,038, describes a conductive fiber that is capable of being sewn, woven or knitted into a conductive mesh.
Another relevant patent is U.S. Pat. No. 6,433,743 by Massey et al. This describes a patch antenna that can be incorporated into a garment. The patch antenna comprises two spaced layers of electrically conductive fabric sandwiched around a non-conductive layer of fabric with a connection between the two conductive layers. The resulting patch is then incorporated into a garment.
GPS antennas have also been incorporated into garments, see Krasner U.S. Pat. No. 6,259,399. In this patent, the inventor describes an antenna “attached to the garment.” This is not the case in this application.
In this application, a non-woven fabric, a conductive fabric or a wire-mesh which is able to conduct microwave energy is used to make a patch antenna. Conductive non-woven fabric is a non-woven fabric that has incorporated a conductive metal. See U.S. Pat. No. 6,841,244 by Foss et al. This patent describes an anti-microbial fiber that contains an additive comprised of “a zeolite of a metal selected from the group consisting of silver, zinc, copper and tin.”
The object of this invention is to describe a method for incorporating antennas, electronic filter components, and microwave circuits into woven and non-woven fabrics. In the preferred embodiment of this invention, a layer or layers of conductive fabric comprises the conductive material upon which microwave energy can be channeled producing an antenna, electronic filter components or microwave circuits. This conductive fabric is encapsulated or fused in layers of non-conductive fabric. Non-woven fabrics are broadly defined as sheet or web structures bonded together by entangling fiber or filaments (and by perforating films) mechanically, thermally or chemically. They are flat, porous sheets that are made directly from separate fibers or from molten plastic or plastic film. They are not made by weaving or knitting and do not require converting the fibers to yarn. Non-woven fabrics are engineered fabrics that may have a limited life, may be single-use fabric or may be a very durable fabric. Non-woven fabrics also provide specific functions such as absorbency, liquid repellency, resilience, stretch, softness, strength, flame retardancy, washability, cushioning, filtering, bacterial barrier and sterility.