http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-844559-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_66c37c127b4c84bee2f039e646d7a7ed |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G01S1-02 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G01S1-02 |
| filingDate | 1958-10-03-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1960-08-17-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-844559-A |
| titleOfInvention | Omnidirectional beacon antenna |
| abstract | 844,559. Aerials. STANDARD TELEPHONES & CABLES Ltd. Oct. 3, 1958 [Oct. 10, 1957], No. 31670/58. Addition to 772,120. Class 40(7). An aerial system suitable for use at a TACAN radio beacon station and capable of producing the required multilobed rotating radiation pattern is constructed with a view to maintaining an adequate depth of modulation up to high angles of elevation. This is done by reducing in length the rotating parasitic elements forming the pattern lobes as compared with similar elements in prior art aerial systems and by arranging the shortened elements in groups. The embodiment shown comprises a vertical central array of four cylindrical dipoles 7, 8, 9, and 10. These dipoles are coaxial with a central feeder system described in detail with reference to Fig. 2 (not shown) which supplies energy to them in the proportions 1:2:2:1 and with relative phase relationships -45 degrees: -30 degrees: + 30 degrees: -45 degrees. The array is stationary and is enclosed in a dielectric cylinder 2. Surrounding the cylinder 2 is the rotating part of the structure consisting of inner and outer dielectric cylinders 4 and 6, dielectric cap 23, and conductive counterpoise surface 24. The whole aerial system is mounted in a stationary dielectric radome 28 on a bottom support 29. The outer rotating cylinder 6 carries nine equally spaced groups of parasitic elements. The arrangement of elements in one group is shown in Fig. 3. For operation at a frequency of approximately 1,000 mc/s. the element 30 is 7 inches long and the elements 31 and 32 on either side of it 5 inches long. Above the element 30 is element 33 of length 4# inches and, to the side of this, element 34 seven inches long. Elements 31 and 32 are made of resistance wire and the remaining elements of copper wire. There is a single group of parasitic elements mounted on the inner cylinder 4 arranged as shown in Fig. 4. Here the elements 35 and 36 are each 6¢ inches long and the V-elements 37 and 38 which serve to increase the coupling between them have 3“ inch legs set at an angle of 60 degrees. The upper element 39 is 4¥ inches long and all the elements are of copper wire. The Specification gives full details of the positioning of the elements relative to each other and to the central array for the frequency mentioned. There is also described with reference to Fig. 5 (not shown) a suitable group of outer parasitic elements for use with a central array of seven vertically aligned kiconical radiators. An explanation of the theory involved is given, reference being made to the vector diagrams and curves of Figs. 6 to 11 (all not shown). The reason that short parasitic elements of the order of half a wavelength long are used is that these have definite centres of radiation which do not shift appreciably with any change of frequency. Further, short elements are easier to place to obtain optimum spacing and radiation phasing. |
| priorityDate | 1957-10-10-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 15.