Multiple beam communication network with beam selectivity

• US 6,008,923 A
• Filed: 03/16/1998
• Issued: 12/28/1999
• Est. Priority Date: 03/16/1998
• Status: Expired due to Fees

• Current Assignee: Plato, Inc. (Edmentum Ultimate Holdings LLC)
• Original Assignee: NetSchools Corporation (Edmentum Ultimate Holdings LLC)
• Inventors: Samdahl, Roger, Milewski, Richard A.
• Primary Examiner(s): NEGASH, KINFE MICHAEL
• Application Number:
  US09/040,330
• Time in Patent Office: 652 Days
• Field of Search: 359/172, 359/152, 359/159, 359/125, 359/113, 359/117, 340/825-72
• US Class Current: 398/127
• CPC Class Codes: H04B 10/1149 Arrangements for indoor wireless networking of information
• CPC Class Codes: H04B 10/40 Transceivers

Abstract

A space multiplexed wireless interconnection system employs an array of overhead access points in a first plane and selected client node points at arbitrary locations and orientations in a second plane, with server transceivers disposed in an ordered array at the access points and illuminating a radiation region over a substantial portion in said second plane, and with at least one complementary transceiver disposed in the second plane in a client node host device, wherein at least one of the complementary transceivers provides a radiation and reception pattern sufficiently narrow to capture one and only one of the first access points for a session of communication so that the server transceivers can control communication with multiple complementary transceivers and each complementary transceiver can communicate with only one server transceiver.

Claims

1. A system for space division multiplexed communication between first elements in a first plane and second elements in a second plane, said first plane being substantially parallel to said second plane, said system comprising:

first transceivers disposed in an array according to a configuration at first access points in said first plane, each one of said first transceivers illuminating a radiation region over a substantial portion in said second plane; and

at least one second transceiver disposed in said second plane in a host device, said second transceiver projecting a first radiation and reception pattern directly onto said first plane with functionally uniform radiation in a first field of view with preselected attenuation outside of said first field of view, said first radiation pattern being sufficiently narrow and positioned to capture one and only one of said first access points for a session of communication so that said first transceivers can control communication with multiple second transceivers and each said second transceiver can communicate with only one first transceiver.

2. The system according to claim 1 wherein said array configuration for said first transceivers is fixed in a Cartesian grid pattern, wherein said first radiation and reception pattern of said second transceiver is circular in shape in said second plane and has a diameter not substantially exceeding the closest separation between two said first transceivers.

3. The system according to claim 2 wherein said first radiation pattern is positioned along a circle at an odd number of fixed positions.

4. The system according to claim 3 wherein said second transceiver includes an odd number of radiators at fixed positions centered on said circle and wherein said first radiation pattern of each said radiator is uniform in diameter and exceeds spacing of the closest separation between two said first transceivers.

5. The system according to claim 1 wherein said first transceivers are disposed along a ceiling of an enclosed room and wherein radiators of each said second transceiver are disposed in said host device opposing said first transceivers, and said host device being portable.

6. The system according to claim 5 wherein said portable host device is selected from the list including a portable personal computer, a printer, earphones, an instrument, a remote sensing device, a remote data storage device, a remote data collection device, display device, a robotics device.

7. The system according to claims 1 wherein said positioning is independent of placement of said host device.

8. The system according to claim 1 wherein said system is a satellite to ground communication system.

9. The system according to claim 1 wherein each said second transceiver comprises a transmitting element and a receiving element, said receiving element having a field of view substantially coextensive with the radiation pattern of said transmitting element.

10. A method for space division multiplexed communication between first elements in a first plane and second elements in a second plane, wherein said first plane is substantially parallel to said second plane, said method comprising the steps of:

disposing first transceivers in an array according to a configuration at first access points in said first plane;

illuminating with each one of said first transceivers a radiation region over a substantial portion in said second plane;

disposing in said second plane at least one second transceiver in a host device;

projecting with said at least one second transceiver a first radiation and reception pattern directly onto said first plane with functionally uniform radiation in a first field of view and with preselected attenuation outside of said first field of view, said first radiation pattern being sufficiently narrow and positioned to capture one and only one of said first access points for a session of communication so that said first transceivers can control communication with multiple second transceivers and each said second transceiver can communicate with only one first transceiver;

generating at each one of said first transceivers a beacon signal;

listening at each one of said second transceivers for said beacon signals;

if at said second transceiver a plurality of beacon signals is heard, causing at said second transceiver said radiation pattern position of said first radiation and reception pattern to change;

thereafter

listening again at said second transceiver for said beacon signals; and

upon hearing at said second transceiver one and only one of said beacon signals, conducting a point-to-point communication session between said second transceiver and the selected first transceiver.

11. The method according to claim 10 wherein said radiation pattern is changed along a circular track.