Microstrip antenna

• US 5,635,942 A
• Filed: 10/24/1994
• Issued: 06/03/1997
• Est. Priority Date: 10/28/1993
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Murata Manufacturing Co Limited
• Inventors: Kushihi, Yuichi, Saitoh, Yasuaki, Michishita, Kenshi
• Primary Examiner(s): Wimer, Michael C.
• Application Number:
  US08/327,986
• Time in Patent Office: 953 Days
• Field of Search: 343/700 MS, 343/906, 343/702
• US Class Current: 343/700.0MS
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40
• CPC Class Codes: H01Q 9/045 with particular feeding means for circular polarisation H01Q9/0428

Abstract

A microstrip antenna (4) has a radiation electrode (2) and a ground electrode (3) which are formed on upper and lower surfaces of a dielectric substrate (1) respectively. A feeding terminal electrode (2c) of the radiation electrode (2) is formed on the lower surface of the dielectric substrate (1), which is provided with the ground electrode (3), and is insulated from the ground electrode (3). A feeding point (2a) of the radiation electrode (2) is connected with the feeding terminal electrode (2c) by a through-hole electrode (2b). The feeding terminal electrode (2c) is formed in the same plane as the ground electrode (3). In another embodiment of the invention, a through-hole electrode (12b) extends from a feeding point (12a) to the plane of the ground electrode (13).

Claims

1. A microstrip antenna comprising:

a dielectric substrate having a first major surface and a second major surface which is opposite to said first major surface;

a ground electrode on said first major surface of said dielectric substrate;

a radiation electrode on said second major surface of said dielectric substrate; and

a feeding terminal electrode extending from a feeding point on said radiation electrode toward said first major surface through the inside of said dielectric substrate, a forward end portion of said feeding terminal electrode being formed so as to terminate substantially at a plane including said ground electrode while being insulated from said ground electrode;

and further wherein said dielectric substrate has an opening portion in a region covered with said radiation electrode,

said feeding terminal electrode having a bent portion defined by partially bending said radiation electrode into said opening portion, and said forward end portion being defined by further bending a forward end of said bent portion to be included in said plane including said ground electrode.

2. A microstrip antenna in accordance with claim 1, in combination With a printed circuit board, said microstrip antenna being mounted on said printed circuit board with said first major surface of said dielectric substrate being directed toward said printed circuit board.

3. A microstrip antenna in accordance with claim 2, wherein said ground electrode and said forward end portion of said feeding terminal electrode are both conductively connected to circuit patterns on a surface of said printed circuit board adjacent to said first major surface of said dielectric substrate.