Dual frequency microstrip antenna
First Claim
Patent Images
1. A dual frequency microstrip antenna comprising:
- a dielectric substrate which has a top surface and a bottom surface;
a conductive layer attached to the bottom surface of the dielectric substrate thereby forming a ground plane;
a feeding means attached to the ground plane and conducting first and second radio frequency signals into the conductive layer;
said first radio frequency signal having a first frequency FH, said second radio frequency signal having a second frequency FL, said second frequency being lower than said first frequency;
a conductive patch attached to the top surface of the dielectric substrate, said conductive patch having at least one of a plurality of slots which are in the conductive patch and reduce the first frequency of the first radio frequency signal, said plurality of slots thereby affecting a ratio of FH /FL ; and
shorting means attached between said conductive patch and said conductive layer, said shorting means providing an electrical short circuit with conducting pins at locations on the conductive patch to the conductive layer and raising the second frequency of the second radio frequency signal thereby causing a variation in the ratio of FH /FL, said locations including positions in said conductive patch where high order modal electric fields are weakest so that their presence will not disturb high frequency operation, thus providing an independent means to control FL.
1 Assignment
0 Petitions
Accused Products
Abstract
A single element patch microstrip antenna for dual frequency operation is disclosed. By placing shorting pins at appropriate locations in the patch, the ratio of two band frequencies can be varied from 3 to 1.8. By also introducing slots in the patch, the ratio can be reduced from 3 to less than 1.3. A second embodiment of the antenna uses a c-shaped slot to obtain an even smaller ratio of two band frequencies.
53 Citations
12 Claims
-
1. A dual frequency microstrip antenna comprising:
-
a dielectric substrate which has a top surface and a bottom surface; a conductive layer attached to the bottom surface of the dielectric substrate thereby forming a ground plane; a feeding means attached to the ground plane and conducting first and second radio frequency signals into the conductive layer;
said first radio frequency signal having a first frequency FH, said second radio frequency signal having a second frequency FL, said second frequency being lower than said first frequency;a conductive patch attached to the top surface of the dielectric substrate, said conductive patch having at least one of a plurality of slots which are in the conductive patch and reduce the first frequency of the first radio frequency signal, said plurality of slots thereby affecting a ratio of FH /FL ; and shorting means attached between said conductive patch and said conductive layer, said shorting means providing an electrical short circuit with conducting pins at locations on the conductive patch to the conductive layer and raising the second frequency of the second radio frequency signal thereby causing a variation in the ratio of FH /FL, said locations including positions in said conductive patch where high order modal electric fields are weakest so that their presence will not disturb high frequency operation, thus providing an independent means to control FL. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A dual frequency microstrip antenna comprising:
-
a dielectric substrate which has a top surface and a bottom surface; a conductive layer attached to the bottom surface of the dielectric substrate thereby forming a ground plane; a feeding means attached to the ground plane and conducting first and second radio frequency signals into the conductive layer;
said first radio frequency signal having a first frequency FH, said second radio frequency signal having a second frequency FL, said second frequency being lower than said first frequency; anda conductive patch attached to the top surface of the dielectric substrate, said conductive patch having a c-shaped slot which forms a ring in the conductive patch which has an effective open-circuited transmission line length of about one half of the rectangular ring'"'"'s length, said c-shaped slot producing a separation between said first frequency and said second frequency said separation decreasing as transmission line length of the c-shaped slot increases. - View Dependent Claims (12)
-
Specification