ARRAY ANTENNA

• US 20110084880A1
• Filed: 12/07/2009
• Published: 04/14/2011
• Est. Priority Date: 12/05/2008
• Status: Active Grant

• Current Assignee: Sakura Tech Corporation
• Original Assignee: Sakura Tech Corporation
• Inventors: Sakai, Fuminori, Ohta, Kazuo
• Granted Patent: US 8,427,372 B2
• Time in Patent Office: Days
• US Class Current: 342/375
• CPC Class Codes: G01S 13/0209 Systems with very large relative bandwidth, i.e. larger than 10 %, e.g. baseband, pulse, carrier-free, ultrawideband
• CPC Class Codes: G01S 13/87 Combinations of radar systems, e.g. primary radar and secondary radar
• CPC Class Codes: G01S 2013/0254 Active array antenna
• CPC Class Codes: G01S 7/282 Transmitters
• CPC Class Codes: G01S 7/285 Receivers
• CPC Class Codes: H01Q 21/08 the units being spaced along or adjacent to a rectilinear path waveguide fed H01Q21/0037
• CPC Class Codes: H01Q 3/2682 Time delay steered arrays
• CPC Class Codes: H01Q 3/30 varying the relative phase between the radiating elements of an array H01Q3/2605, H01Q3/2658, H01Q3/2682, H01Q3/44 take precedence

Abstract

Disclosed is an electronic scanning array antenna which can be used as a UWB radar having an occupied band of not less than 500 MHz. An impulse generator is connected to each of a plurality of antenna elements constituting the electronic scanning array antenna, and a transmission trigger time to each of the impulse generators connected to the antenna elements is changed, whereby the phase of radio waves emitted from an antenna is equivalently changed. Moreover, a transmission trigger repletion interval is changed to thereby control a direction of a beam emitted from the array antenna. As means of changing a transmission trigger timing to each of the impulse generators connected to the antenna elements, a method of changing a frequency of a transmission trigger pulse and a method of changing a pulse position are adopted.

Claims

1. An electronic scanning array antenna comprising:

a plurality of antenna elements constituting the electronic scanning array antenna are respectively connected to a single trigger generator through impulse generators;

delay lines with different numbers are provided between the trigger generator and each of the impulse generators; and

a time difference occurs between inputs to each of the antenna elements to thereby control a direction of a beam emitted from the electronic scanning array antenna.

4. The electronic scanning array antenna according to claim 1, wherein the trigger generator is a variable frequency trigger generator.

5. The electronic scanning array antenna according to claim 1, wherein a switch which performs on/off switching control of an input to each of the impulse generators based on an instruction of an on/off switching control signal is provided on the input side of each of the impulse generators.

9. The electronic scanning array antenna according to claim 1, wherein a narrowband filter is inserted into an output of the impulse generator.

2. An electronic scanning array antenna comprising:

a plurality of antenna elements constituting the electronic scanning array antenna are respectively connected to a single trigger generator through a correlation detecting circuit or a sampling circuit;

delay lines with different numbers are provided between the trigger generator and each of the correlation detecting circuits or each of the sampling circuits; and

a time difference occurs between inputs to each of the antenna elements to thereby control a direction of a beam received by the electronic scanning array antenna.

10. The electronic scanning array antenna according to claim 2, wherein a narrowband filter is inserted into an impulse generation output in the correlation detecting circuit or an impulse generation output in the sampling circuit.

3. An electronic scanning array antenna comprising:

a plurality of antenna elements constituting the electronic scanning array antenna are respectively connected to a single trigger generator through impulse generators;

the plurality of antenna elements are respectively connected to the trigger generator through a correlation detecting circuit or a sampling circuit;

delay lines with different numbers are provided between the trigger generator and each of the impulse generators, and, at the same time, delay lines with different numbers are provided between the trigger generator and each of the correlation detecting circuits or each of the sampling circuits;

a time difference occurs between inputs to each of the antenna elements to thereby control a direction of a beam emitted from the electronic scanning array antenna; and

the time difference occurs between the inputs to each of the antenna elements to thereby control a direction of a beam received by the electronic scanning array antenna.

6. An electronic scanning array antenna, wherein:

an impulse generator is connected to each of a plurality of antenna elements constituting the electronic scanning array antenna;

each of the impulse generators is connected to a single pulse position modulator receiving an input of a clock pulse from a clock generator;

delay lines with different numbers are provided between the pulse position modulator and each of the impulse generators; and

a time difference occurs between inputs to each of the antenna elements to thereby control a direction of a beam emitted from the electronic scanning array antenna.

7. An electronic scanning array antenna wherein:

a correlation detecting circuit or a sampling circuit is connected to each of a plurality of antenna elements constituting the electronic scanning array antenna;

each of the correlation detecting circuits or each of the sampling circuits is connected to a signal pulse position modulator receiving an input of a clock pulse from a clock generator;

delay lines with different numbers are provided between the pulse position modulator and each of the correlation detecting circuits or each of the sampling circuits; and

a time difference occurs between inputs to each of the antenna elements to thereby control a direction of a beam received by the electronic scanning array antenna.

8. The electronic scanning array antenna according to claim 7, wherein a plurality of delay lines are connected in series to the pulse position modulator;

a phase comparator is connected to a tail end or the middle of a wiring through which the plurality of delay lines are connected in series to the pulse position modulator;

a phase of a trigger signal at a position where the phase comparator is connected and a phase of a signal output from the clock generator are compared with each other by the phase comparator;

the comparison result of the phase comparator is input to the clock generator or input to a pulse position controller which inputs a pulse position control signal to the pulse position modulator.