Spiral antenna

• US 9,112,268 B2
• Filed: 01/22/2013
• Issued: 08/18/2015
• Est. Priority Date: 07/25/2012
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Tanabe, Masahiro
• Primary Examiner(s): Ho, Tan
• Application Number:
  US13/746,692
• Publication Number:
  US 20140028528A1
• Time in Patent Office: 938 Days
• Field of Search: 343/895
• US Class Current: 1/1
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 9/27 Spiral antennas

Abstract

According to one embodiment, a spiral antenna includes at least one spiral arm and a connection portion which connects an end of the spiral arm to an adjacent spiral arm.

Claims

1. A spiral antenna comprising:

at least one spiral arm; and

a connection portion which connects an end of said spiral arm to an adjacent spiral arm, wherein

at said connection portion, a current reflected by the end of said spiral arm and a current flowing to the adjacent spiral arm cancel each other.

2. A spiral antenna comprising:

at least one spiral arm; and

a connection portion which connects an end of said spiral arm to an adjacent spiral arm, wherein

when transmitting/receiving a right-handed circularly polarized wave, a left-handed circularly polarized wave of an outer loop radiated field of said spiral arm is canceled by a left-handed circularly polarized wave of an inner spiral radiated field of said spiral arm at a frequency at which a phase difference between the left-handed circularly polarized waves is substantially 180°

.

3. A spiral antenna comprising:

at least one spiral arm; and

a connection portion which connects an end of said spiral arm to an adjacent spiral arm, wherein

when transmitting/receiving a left-handed circularly polarized wave, a right-handed circularly polarized wave of an outer loop radiated field of said spiral arm is canceled by a right-handed circularly polarized wave of an inner spiral radiated field of said spiral arm at a frequency at which a phase difference between the right-handed circularly polarized waves is substantially 180°

.