Beamformer for multi-beam broadcast antenna
AssigneeEMS Technologies, Inc.
InventorJames M. Howell
Life of this patent
Estimating the term…
Abstract
A phased array antenna system operative to broadcast multiple beams that each include coded data for specific users located within the coverage area of the corresponding beam. An appropriate receiver then receives and decodes a particular beam to extract the specific data for a corresponding user. Multiple users may be assigned to each beam using frequency division or orthogonal code multiplexing, and the user data may be encoded into the beams using frequency shift key or phase shift key encoding. For each coding technique, the encoded antenna control signals are combined into a total gain and total phase shift control signal, which drives a single phase and gain control device for each antenna element. In addition, a single data modulator generates the coding parameters for the entire communication system.
Claims37
A method for operating a phased array antenna system having a plurality of antenna elements, comprising the steps of:
- receiving data for a plurality of users;
- assigning the data to a plurality of beams;
- defining a control signal for each antenna element in which each control signal comprises an associated beam component corresponding to each beam, and computing a total gain and a total phase shift for each antenna element comprising the vector sum of the beam components associated with the corresponding antenna element;
- encoding each beam with the data assigned to that beam by generating the control signals to drive the antenna elements to generate the beams, wherein the combination of the control signals generated for all of the antenna elements causes the antenna to emit the plurality beams in which each beam carries encoded data for its assigned users;
- and
- broadcasting the beams to deliver the data to the users.
A multi-beam phased array antenna system comprising:
- a plurality of antenna elements;
- a phase and gain control device associated with each antenna element;
- and
- a beam forming computer configured to generate control signals to drive the phase and gain control devices to create multiple beams, wherein:
- each beam is assigned data corresponding to users located within a coverage associated with the corresponding beam,
- a control signal for each antenna element comprises a total gain and a total phase shift,
- the control signal control signal for each antenna element comprises a vector sum of beam components in which one beam component corresponds to each beam, and
- each beam component comprises a vector sum of data signals for users assigned to the corresponding beam, wherein each data signal comprises a coding parameter representing data for an associated user.
A multi-beam phased array antenna system comprising:
- a plurality of antenna elements;
- a phase and gain control device associated with each antenna element;
- a code selector configured to identify desired coding parameter sets;
- a beam selector configured to identify desired beam sets;
- and
- a beam forming computer configured to generate control signals to drive the phase and gain control devices to create multiple beams, wherein:
- each beam is assigned data corresponding to users located within a coverage associated with the corresponding beam,
- a control signal for each antenna element comprises a total gain and a total phase shift, and
- the control signal control signal for each antenna element comprises a vector sum of beam components in which one beam component corresponds to each beam, and
- each beam component comprises a vector sum of data signals for users assigned to the corresponding beam, wherein each data signal comprises a coding parameter representing data for an associated user.
In a beam former for use with a phased array antenna system, an improvement comprising:
- the beam former being operative for coding the data and combining the coded data into control signals to drive a plurality of antenna elements to broadcast a plurality of beams, wherein each beam carries data assigned to a plurality of users located within a coverage area associated with the beam, and the control signal for each antenna element comprises a total gain and a total phase shift comprising a vector sum of beam components in which each beam component is associated with a corresponding beam.
The method beam former of 32, wherein:
- multiple users are assigned to each beam using frequency division multiplexing;
- and
- the user data is encoded into each beam using a phase shift key coding technique.
Dependencies are inferred from the claim text.