The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 20, 1981
Filed:
Nov. 29, 1979
Franz Beyer, Munich, DE;
Siegfried Sedlmair, Groebenzell, DE;
Siemens Aktiengesellschaft, Berlin & Munich, DE;
Abstract
A P-I-N type diode high frequency switch in a secondary radar interrogation device working with ISLS and RSLS and consisting of a transmitter, two receivers and two antennas. So as to reduce the high cost for P-I-N type diodes, including driver stages for the transmission and reception separation and to eliminate the necessity of an antenna switching unit, the terminals 19 and 20 of a pair of antennas are directly connected through single lines 23 and 24 to band pass filters 5 and 6 connected to respective receivers 7 and 8 with the band pass filters 5 and 6 blocking the transmission signal and allowing reception of received signals and wherein the electrical lengths of the line and the band pass filter is such that the input impedance corresponding to no-load operation occurs at the corresponding antenna terminal for the transmission frequency. The invention can be used in secondary radar transponders operating with two antenna diversity and the high frequency switch of the invention can be used in both civil secondary radar interrogation devices as well as military IFF interrogation devices as, for example, in ground stations.