Offset active antenna having two reflectors

• US 5,321,413 A
• Filed: 12/23/1992
• Issued: 06/14/1994
• Est. Priority Date: 12/23/1991
• Status: Expired due to Fees

• Current Assignee: Alcatel Espace
• Original Assignee: Alcatel Espace
• Inventors: Lenormand, Regis
• Primary Examiner(s): Hajec, Donald
• Assistant Examiner(s): Ho, Tan
• Application Number:
  US07/996,156
• Time in Patent Office: 538 Days
• Field of Search: 343/753, 343/754, 343/755, 343/781 P, 343/781 CA, 343/786, 343/853
• US Class Current: 343/755
• CPC Class Codes: H01Q 19/104 using a substantially flat reflector for deflecting the radiated beam, e.g. periscopic antennas periscopic fed Cassegrain antennas H01Q19/191; passive relays H04B7/145
• CPC Class Codes: H01Q 19/192 with dual offset reflectors

Abstract

An offset type active antenna having two reflectors in a periscopic configuration. A radio lens is provided at the focii of the two reflectors. It comprises a collector and a primary array that is considerably larger in size than the collector. The "small" sources of the collector are in a geographically identical one-to-one correspondence with the "big" sources of the primary array, and they are respectively connected together via devices for providing fine phase adjustment.

Claims

1. A two-reflector offset type active antenna including a radio wave lens at a common focal point of first and second confocal reflectors, said lens having a collector with a collector first face that receives and picks up a concentrated and reflected beam derived from a beam emitted by an active source of the antenna towards said first reflector that encounters said beam, said collector being placed at the focus of the first reflector, and a primary array having an opposite face which re-emits, towards said second reflector, energy transmitted to a second face of said primary array from the collector first face by means of interconnections, said primary array being placed at the focus of said second reflector;

the primary array and the collector have plural sources, respectively, and the sources of the collector are respectively connected in a one-to-one geometrical configuration preserving relationship to respective ones of the sources of the primary array; and

wherein the connection between each source of the collector and the corresponding source of the primary array includes a device providing fine phase adjustment.

2. An antenna according to claim 1, wherein a first face surface area of the sources of the collector are considerably smaller in size than a second face surface area of the sources of the primary array, and said collector is considerably smaller than said primary array.

3. An antenna according to claim 2, wherein dimensions of the surface area of the primary array sources are of the order of several times greater than dimensions of the surface area of the collector sources.

4. An antenna according to claim 1, wherein each source of the primary array is built up from an integer number of juxtaposed smaller sources each source of which is connected to a source in the collector having the geographical position that corresponds to the position of said source in the primary array by means of its own phase adjustment circuit.

5. An antenna according to claim 1, wherein the collector and the primary array are carried by surfaces that are not parallel.