Multibeam digital beam-forming global navigation receivers

Abstract

An apparatus for positioning comprises an antenna array and a digital beam-forming processor. The antenna array comprises a plurality of antenna elements arranged as at least one of a non-planar array, a non-contiguous distributed array or both. The antenna elements produce a plurality of element signals. The digital beam-forming processor is coupled to the antenna array, and is configured to receive the element signals, process the received element signals using a plurality of beam weighting vectors, and generate a plurality of concurrent shaped beams. A first shaped beam of the concurrent shaped beams comprises a null at a first direction to reject a first signal from a first navigation satellite. A second shaped beam of the concurrent shaped beams comprises a null at a second direction to reject a second signal from a second navigation satellite.

What is claimed is: 
     
         1 . An apparatus for positioning, comprising:
 an antenna array comprising a plurality of antenna elements arranged as at least one of a non-planar array, a non-contiguous distributed array or both, the antenna elements producing a plurality of element signals; and   a digital beam-forming processor coupled to the antenna array, the digital beam-forming processor being configured to receive the element signals, process the received element signals using a plurality of beam weighting vectors, and generate a plurality of concurrent shaped beams, wherein a first shaped beam of the concurrent shaped beams comprises a null at a first direction to reject a first signal from a first navigation satellite, and wherein a second shaped beam of the concurrent shaped beams comprises a null at a second direction to reject a second signal from a second navigation satellite.   
     
     
         2 . The apparatus of  claim 1  further comprising a multichannel receiver coupled to the digital beam-forming processor, the multichannel receiver comprising correlators for performing correlation of the first shaped beam and an acquisition code associated with the first navigation satellite. 
     
     
         3 . The apparatus of  claim 1 , wherein the antenna array comprises conformal antenna elements. 
     
     
         4 . The apparatus of  claim 1 , wherein the antenna array comprises non-identical antenna elements. 
     
     
         5 . The apparatus of  claim 1 , wherein the antenna array comprises antenna elements covering different fields of view. 
     
     
         6 . The apparatus of  claim 1 , wherein the apparatus is on a moving platform. 
     
     
         7 . The apparatus of  claim 1 , wherein the digital beam-forming processor is remotely located from the antenna elements. 
     
     
         8 . The apparatus of  claim 1 , wherein the beam weighting vectors are dynamically adjusted and wherein the digital beam-forming processor is further configured to steer at least one of the concurrent shaped beams using the dynamically adjusted beam weighting vectors to follow an angular position of a navigation satellite. 
     
     
         9 . The apparatus of  claim 1 , wherein the concurrent shaped beams comprise a plurality of concurrent spot beams. 
     
     
         10 . The apparatus of  claim 1 , wherein the concurrent shaped beams track one navigation satellite or a plurality of navigation satellites concurrently, the one or more navigation satellites being included in a single space-based navigation system or in a plurality of independent space-based navigation systems. 
     
     
         11 . The apparatus of  claim 1 , wherein each of the beam weighting vectors comprises at least one selected from a group consisting of a phase correction factor, an amplitude correction factor, and a time-delay correction factor. 
     
     
         12 . The apparatus of  claim 1 , wherein the beam weighting vectors are dynamically adjusted and wherein the digital beam-forming processor is further configured to steer the concurrent shaped beams using the dynamically adjusted beam weighting vectors. 
     
     
         13 . The apparatus of  claim 1 , wherein the first navigation satellite and the second navigation satellite are included in a same space-based navigation system. 
     
     
         14 . An apparatus for positioning, comprising:
 an antenna array comprising a plurality of antenna elements arranged as at least one of a non-planar array, a non-contiguous distributed array or both, the antenna elements producing a plurality of element signals; and   a digital beam-forming processor coupled to the antenna array, the digital beam-forming processor being configured to receive the element signals, process the received element signals using a plurality of beam weighting vectors, and generate a plurality of concurrent shaped beams, wherein a first shaped beam of the concurrent shaped beams comprises a null at a first direction to reject a first signal from a first navigation satellite in a first space-based navigation system, and wherein a second shaped beam of the concurrent shaped beams comprises a null at a second direction to reject a second signal from a second navigation satellite in a second space-based navigation system.   
     
     
         15 . The apparatus of  claim 14 , wherein the beam weighting vectors are dynamically altered and wherein the digital beam-forming processor is configured to steer the concurrent shaped beams using the dynamically altered beam weighting vectors. 
     
     
         16 . The apparatus of  claim 14  further comprising a multichannel receiver coupled to the digital beam-forming processor, the multichannel receiver comprising correlators for performing correlation of the first shaped beam and an acquisition code associated with the first navigation satellite. 
     
     
         17 . A method for locating a satellite, the method comprising the operations of:
 (a) obtaining a plurality of element signals from an antenna array, the antenna array comprising a plurality of antenna elements arranged as at least one of a non-planar array, a non-contiguous distributed array or both, the antenna elements producing the element signals;   (b) processing the element signals, by using a digital beam-forming processor coupled to the antenna array and a plurality of beam weighting vectors, to generate a plurality of concurrent shaped beams, each of the concurrent shaped beams being configured to track one of a plurality of satellites within a field of view and providing respective data on the respective one of the satellites being tracked; and   (c) performing an analysis of all respective data provided by the concurrent shaped beams, using a multichannel receiver coupled to the digital beam-forming processor, to obtain location information on the satellites being tracked.   
     
     
         18 . The method of  claim 17 , further comprising the operations of:
 (d) turning off one of the concurrent shaped beams, the one of the concurrent shaped beams having been pointing at a respective satellite; and   (e) performing an analysis of all respective data provided by the remaining concurrent shaped beams, using the multichannel receiver, to obtain location information on the remaining satellites being tracked.   
     
     
         19 . The method of  claim 18 , further comprising the operation of:
 (f) repeating the operations (d) and (e) for each of the remaining satellites being tracked   
     
     
         20 . The method of  claim 19 , further comprising the operation of:
 (g) comparing results from all analyses performed in the operation (e) to determine which one of the concurrent shaped beams produces data containing an interfering satellite signal.