DIRECTIONAL MIMO ANTENNA

• US 20180287671A1
• Filed: 02/23/2018
• Published: 10/04/2018
• Est. Priority Date: 02/24/2017
• Status: Active Grant

• Current Assignee: Antenum, Inc.
• Original Assignee: Ami Research & Development, LLC
• Inventors: Apostolos, John T., Mouyos, William
• Granted Patent: US 10,686,497 B2
• Time in Patent Office: Days
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
• CPC Class Codes: H01Q 21/26 Turnstile or like antennas comprising arrangements of three or more elongated elements disposed radially and symmetrically in a horizontal plane about a common centre
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0604 with predefined switching scheme
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
• CPC Class Codes: H04L 25/0204 of multiple channels
• CPC Class Codes: H04L 25/0224 using sounding signals
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04L 5/06 the signals being represented by different frequencies combined with time-division multiplexing H04L5/26
• CPC Class Codes: H04W 64/003 locating network equipment

Abstract

A Multiple Input Multiple Output (MIMO) antenna system and operating method that provides spatial- and temporal multiplexing with polarization independent operating modes.

Claims

1. A multiplexing method for operating a Multiple Input Multiple Output (MIMO) system in a multipath environment, the MIMO system comprising a transmit subsystem comprising two or more transmit antennas and a receive subsystem comprising two or more receive antennas, the multiplexing method comprising:

in a training mode,

activating a first transmit antenna to transmit a predetermined pilot signal, determining a first angle of arrival (AOA) and a first time of arrival (TOA) from one or more signals received at the receive subsystem;

activating a second transmit antenna to transmit a predetermined pilot signal, and determining a second angle of arrival (AOA) and a second time of arrival (TOA) from one or more signals received at the receive subsystem;

deriving a spatial frequency and temporal frequency transfer function from the signals received at the receive subsystem;

in an operating mode,

using the spatial and temporal transfer function to discriminate signals received at the receive subsystem.

2. The multiplexing method of claim 1 additionally wherein two or more of the receive antennas are directional receiving antennas.

3. The multiplexing method of claim 2 wherein the angles of arrival include an elevational angle and an azimuth angle.

4. The multiplexing method of claim 2 wherein the directional receiving antennas are crossed dipole antennas.

5. The multiplexing method of claim 2 wherein each directional receiving antenna further comprises a structure having sets of antenna elements, with each set of antenna elements including four radiating segments, and further comprising the step of:

combining the outputs of two or more radiating segments in each set of elements, to provide two or more of a horizontal, vertical, left hand or right hand polarization mode.

6. The multiplexing method of claim 2 additionally wherein the directional receiving antennas further comprises four quadrant elements, with each quadrant element further comprising:

a conductive cylinder side section and a feed point;

a first pair of the four quadrant elements positioned opposite to one another along a major axis;

a second pair of the four quadrant elements positioned opposite to one another along the major axis; and

a combining circuit for selectively combining the feed points provided by respective quadrant elements.

7. An apparatus comprising:

a plurality of directional receiving antennas, arranged to receive multiple signals from an array of transmitting antennas;

a plurality of combining circuits, with each combining circuit connected to a respective one of the directional receiving antennas,

to produce a first angle signal indicative of a first angle of arrival (AOA) for one or more signals received when a first transmit antenna is active;

to produce a second angle signal indicative of a second angle of arrival (AOA) when a second transmit antenna is active;

a signal processor,

for deriving a spatial frequency and temporal frequency transfer function from the signals received at the receive subsystem; and

in an operating mode, for using the spatial and temporal transfer function to discriminate signals received at the receive subsystem.