Патент USA US2115789код для вставки
243-872 May 3, 1938. CROSS REFERENCE K. SCHMID 2,115,789 v DIRECTIONAL ANTENNA SYSTEM Filed May 22, 1936 T INVENTOR KURT S HMID BY’ ' ATTORNEY 2,115,789 Patented May 3, 1938 UNITED STATES PATENT OFFICE 2,115,789 DIRECTIONAL ANTENNA SYSTEM Kurt Schmid, Berlin, Germany, assignor to Tele funken Gesellschaft fiir Drahtlose Telegraphie m.‘ b. 11., Berlin, Germany, a corporation of Germany Application May 22, 1936, Serial No. 81,181 In Germany June 4, 1935 (Cl. 250—11) 2 Claims. The present invention is concerned with a weatherproof arrangement for ultra short waves. much as it is suitable in the case of parabolic re?ectors to mount in front of the dipoles a small In the mounting of antennae it happens quite often that their proper operation is seriously im 5 paired by the inclemencies of the weather, bird auxiliary re?ector, the part H of tube J accord ing to this invention may be made of metal or else is metallized inside and out. The embodiments here described embodying the idea of this invention offer the advantage that with limited means the radiators are safeguarded excrements and dead insects. It has been sug~ gested to accommodate the entire antenna as sembly, that is to say, radiator, including re ?ector or tube, inside a box casing permeable to 10 electrical waves. Although the antenna assembly is safeguarded from the e?ects of the weather, one shortcoming of this idea is that the large sur faces of the box offer a high resistance to the wind. from atmospheric agencies and from soiling by animals, while yet causing but little wind resist 10 ance. It will be evident that the basic idea of the invention is not con?ned to the instances here Another disadvantage is that the expenditure for discussed. For instance, also individual dipoles 15 material is so great that it does not warrant the and rows of dipoles of a “Christmas tree” type of directional antenna could be placed inside a tube aim. '~ According to the present invention, only th radiator or radiators are accommodated inside a casing protecting the same against atmospheric 20 agencies, and that the re?ector is built according to aerodynamic principles. An exempli?ed embodiment of the basic idea of the invention is illustrated in Fig. 1. Fig. 2 shows a detail of Fig. 1. Referring to Fig. l, in the focal line of the cyl 25 inder paraboloid P is a tube R. which is closed all around and made of insulation material, there being con?ned in the interior of the said tube a dipole radiator D. The feed line S passed through 30 the re?ector- is con?ned inside the metallic pipe M for the sake of shielding. In such cases, Where metallic shielding is not absolutely necessary, the feeder S could be shielded also by lighter and cheaper material. Now, in order to minimize the 35 wind resistance of the parabolic mirror, the same is not made from sheet metal, but rather from a gauze or wires extending parallel to the dipoles. The way the pipe or tube enclosing the dipoles D should preferably be made is illustrated in Fig. 40 2. For the sake of simplicity, only one pair of di poles D is here illustrated which is directly united with the feeder S. The feeder for the purpose of shielding it is laid inside the metallic tube M which at point 0 is passed through the re?ector 45 (not shown). The pair of dipoles D is placed in the tube J made of insulation material, which at both ends is shut by lids V though the same is shown cut open at the bottom end. Now, inas~ to be safeguarded from the weather or some similar enclosure or container and the posterior re?ector could be built up of a number of parallel wires. It will be understood that the invention 20 could be applied also to antenna arrays compris ing rotary paraboloids, etc. What is claimed is: 1. In combination, a re?ector, a dipole antenna at the focus of said re?ector, said dipole having two arms arranged substantially in the same straight line, a feed line connecting the adjacent ends of said arms with high frequency apparatus, a hollow insulating tube completely surrounding said antenna and having an aperture located in the center thereof for entrance of said feed line, and a metallic shield surrounding said feed line for at least a portion of its length adjacent said insulating tube. 2. In combination, a reflector comprised of per forate metallic material, an antenna at the focus of said reflector, a feed line connecting said an tenna with high frequency apparatus, a hollow insulating tube completely surrounding said an tenna, and a metallic shield surrounding said cs feed line for at least a portion of its length, that portion of said insulating tube farthest removed from the center of said re?ector having a metal surface for re?ecting towards said re?ector rays emanating from said antenna and striking said surface. KURT SCHMID.