Multilayered slot-coupled antenna device

• US 20040125021A1
• Filed: 03/01/2004
• Published: 07/01/2004
• Est. Priority Date: 03/05/2001
• Status: Active Grant

• Current Assignee: Ericsson AB (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson AB (Telefonaktiebolaget LM Ericsson)
• Inventors: Munk, Marco
• Granted Patent: US 7,064,712 B2
• Time in Patent Office: Days
• US Class Current: 343/700MS
• 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 9/0435 using two feed points
• CPC Class Codes: H01Q 9/0457 electromagnetically coupled to the feed line

Abstract

A multilayered slot-coupled antenna device employs a push-pull arrangement of at least two slot-feedline pairs, whereby the feed lines are driven from a common signal source and configured such that changes in antenna centre-frequency and input impedance due to layer offsets are largely compensated.

Claims

1. A multilayered slot-coupled antenna device comprising:

in sequence;

an antenna element (16);

a first dielectric layer (12);

a ground plane (14) having first and second coupling slots (20, 21;

30, 31) formed therein;

a second dielectric layer (11); and

first and second feed lines (22, 23;

32, 33) associated with respective coupling slots, characterised in that the first and second feed lines are connected to a signal-feed port (35) by way of a power divider (25, 26, 27) and the feed lines are configured such that each has a portion distant from the signal-feed port which crosses its respective slot orthogonally thereto, said portions pointing in opposite directions.

2. An antenna device according to claim 1 in which the signal feed lines are arranged such that, in use and with reference to the locations of the feed lines at the slots, a signal applied to the signal-feed port is divided substantially equally between the feed lines and in opposite phases.

3. An antenna device according to claim 1 or claim 2 in which the first and second coupling slots comprise elongate apertures (20, 21) spaced apart from each other and lying along a common axis and the first and second feed lines (22,23) lie orthogonal to their respective apertures, the free-ends of the feed lines lying on opposite sides of the common axis.

4. An antenna device according to claim 1 or claim 2 in which the first and second coupling slots comprise elongate apertures (30, 31) spaced apart and lying parallel to each other and the first and second feed lines (32, 33) lie orthogonal to their respective apertures, the free-ends of the feed lines pointing away from each other.

5. An antenna device according to claim 1 or claim 2 in which the first and second coupling slots comprise elongate apertures (30, 31) spaced apart and lying parallel to each other and the first and second feed lines (32, 33) have respective first portions (40, 41) lying orthogonal to, and respective continuing portions lying parallel to, the respective apertures.

6. An antenna device according to claim 1 or claim 2 and further comprising third or more coupling slots (44) formed in the ground plane and third or more feed lines (44) associated with respective third or more coupling slots and connected to at least one further signal-feed port (46).

7. An antenna device according to claim 6, comprising third and fourth coupling slots and respectively associated third and fourth feed lines, the third and fourth feed lines being connected to a further signal-feed port by way of a further power divider.

8. An antenna device according to claim 7 in which the antenna element is rectangular in form and the first and second coupling slots (50, 51) lie opposite each other near two of the edges of the rectangular element and the third and fourth coupling slots (52, 53) lie opposite each other near the other two edges of the rectangular antenna element, the feed lines having portions which lie orthogonal to their respective coupling slots.