Antenna device and mobile communication terminal

• US 8,704,716 B2
• Filed: 02/15/2013
• Issued: 04/22/2014
• Est. Priority Date: 11/20/2009
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Kato, Noboru, Sasaki, Jun, Miura, Teppei
• Primary Examiner(s): MANCUSO, HUEDUNG XUAN CAO
• Application Number:
  US13/767,960
• Publication Number:
  US 20130154388A1
• Time in Patent Office: 431 Days
• Field of Search: 343/700.MS, 343/702, 343/748, 343/788, 343/867, 343/895
• US Class Current: 343/702
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/07756 the connection being non-galvanic, e.g. capacitive
• CPC Class Codes: G06K 19/07786 the antenna being of the HF type, such as a dipole
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 1/40 Radiating elements coated with or embedded in protective material
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop
• CPC Class Codes: H04B 5/70 specially adapted for specific purposes

Abstract

An antenna device includes a feeding member including a coil pattern and an emitting member to emit a transmit signal supplied from the feeding member and to receive a receive signal and supplying it to the feeding member. The emitting member includes an opening portion and a slit portion communicating with the opening portion. When seen in plan view from the direction of the winding axis of the coil pattern, the opening portion of the emitting member and the inner region of the coil pattern overlap each other, and the emitting member and the coil pattern overlap each other at least partially.

Claims

1. An antenna device comprising:

a feeding member including a coil pattern;

an emitting member magnetically coupled to the coil pattern and arranged to emit a transmit signal supplied from the feeding member and/or to receive a receive signal and supply the receive signal to the feeding member; and

a conductor member that is opposed to the emitting member;

wherein

the emitting member includes a slit portion, and the emitting member and the conductor member are capacitively coupled to each other on both sides of the slit portion.

2. The antenna device according to claim 1, wherein the emitting member and the conductor member are capacitively coupled to each other via a capacitance assisting element.