# US 8,786,497 B2 · High isolation multiband MIMO antenna system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,497 B2 - Document ID: US8786497B2 - Status: Granted - Kind: B2 - Application number: 12/958,330 - Filed: 2010-12-01 - Published: 2012-06-07 - Granted: 2014-07-22 - Earliest claimed: 2010-12-01 - Assignees: King Fahd University of Petroleum and Minerals - Applicants: Mohammad S. Sharawi - Inventors: Mohammad S. Sharawi - Web page: https://patentgrep.com/patent/US8786497B2 ## CPC - H01Q 1/38: formed by a conductive layer on an insulating support {(patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142)} - H01Q 1/521: {reducing the coupling between adjacent antennas} - H01Q 9/065: {Microstrip dipole antennas (patch antenna H01Q9/0407)} - H01Q 21/28: Combinations of substantially independent non-interacting antenna units or systems {(multiple beam H01Q25/00)} - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) ## Abstract The high isolation multiband MIMO antenna system is a multi-band dual and quad antenna for multiple-input-multiple-output (MIMO) antenna systems. Element and ground plane geometries that can cover a wide range of frequency bands (780 MHz-5850 MHz) are based on the varying some simple geometrical lengths and widths of the elements and ground planes. The MIMO antenna systems can be used for next generation cellular and wireless MIMO communication systems. Several isolation enhancement schemes increase the isolation between adjacent antenna elements. Any combination of the isolation and MIMO antenna system geometries can be created to support different wireless system standards. The novel MIMO antenna systems are disposed within a dielectric substrate area of 50×100 mm2. ## Claims ### Claim 1 A high isolation multiband MIMO antenna system, comprising: a substantially rectangular planar dielectric substrate having a top face and a bottom face; a plurality of electrically conductive microstrip antennas disposed on the substantially planar substrate; at least one ground plane having a substantially L-shaped contour, the at least one ground plane having a substantially rectangular portion and an elongate extension portion, the elongate extension portion extending from the substantially rectangular portion, the substantially rectangular portion and the elongate extension portion being disposed on the substantially planar substrate; feeding points, for feeding signals, the feeding points being electrically connected to the antennas, wherein said plurality of electrically conductive microstrip antennas comprise at least one F-shaped antenna having an elongate portion having opposed first and second ends, the first end thereof being connected to a corresponding feeding point, and first and second orthogonal portions, said first and second orthogonal portions extending orthogonally to an axis of said elongate portion, said first orthogonal portion extending from the second end of said elongate portion, said second orthogonal portion extending from a central region of said elongate portion, said first orthogonal portion having a length associated therewith which is greater than a length associated with said second orthogonal portion. ### Claim 2 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein a width-wise edge of said substantially rectangular portion is flush with a length-wise edge of said substrate and a width-wise edge of said elongate extension portion is flush with a width-wise edge of said substrate. ### Claim 3 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein a width-wise edge of said substantially rectangular portion is parallel to and proximate to a length-wise edge of said substrate. ### Claim 4 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein a width-wise edge of said elongate extension portion is parallel to and proximate to a width-wise edge of said substrate. ### Claim 5 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said substrate has four quadrants, said at least one ground plane comprising four ground planes, each of the quadrants having a corresponding one of the ground planes disposed thereon. ### Claim 6 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said at least one ground plane is disposed on the bottom face of said substrate. ### Claim 7 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said at least one ground plane is disposed on the top face of said substrate. ### Claim 8 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said elongate extension portion has a gap splitting the elongate extension portion into two portions. ### Claim 9 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said elongate extension portion has a plurality of gaps splitting the elongate extension portion into multiple portions. ### Claim 10 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said at least one F-shaped antenna comprises two F-shaped radiator elements disposed on the top face of said planar substrate in diagonally opposed quadrants. ### Claim 11 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said at least one F-shaped antenna comprises one F-shaped radiator element disposed on the top face and one F-shaped radiator element disposed on the bottom surface of said planar substrate. ### Claim 12 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said at least one F-shaped antenna comprises four F-shaped elements disposed on the top surface of said planar substrate, one in each quadrant of said substrate. ### Claim 13 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said plurality of antennas comprises two serpentine-shaped elements disposed on the top face of said planar substrate in diagonally opposed quadrants, wherein each said serpentine-shaped elements comprises a plurality of coils, each said coil having a width associated therewith which is equal to widths of adjacent ones of said coils. ### Claim 14 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said plurality of antennas comprises a first serpentine-shaped element disposed on the top face and a second serpentine-shaped element disposed on the bottom face of said planar substrate, wherein each of said first and second serpentine-shaped elements comprises a plurality of coils, each said coil having a width associated therewith which is equal to widths of adjacent ones of said coils. ### Claim 15 (depends on 1) The high isolation multiband MIMO antenna system according to claim 1, wherein said plurality of antennas comprises a first pair of antennas resonant in a first frequency band and a second pair of antennas resonant in a second frequency band, the first pair of antennas being disposed in diagonally opposed quadrants of said substrate and the second pair of antennas being disposed in a different pair of diagonally opposed quadrants of said substrate.