Digital Beamforming Arrays
Next-Generation Digital-Beamforming (DBF) Arrays
Our next generation of DBF antenna technology has extended the RF coverage of the antenna from S-band to L/S/C telemetry bands simultaneously. We have utilized a tri-band array to demonstrate the first implementation of a new architecture that we call Universal Beamforming Technology (UBT), which can be applied to a wide variety of DBF applications, including communications, radar and telemetry.
We partnered with an antenna element provider to demonstrate the following proof-of-concept hardware for a US Government customer:
RF operation 1 – 6 GHz
Scan extent: +/- 90 deg Azimuth and Elevation (with roll-off)
Target acquisition/tracking at <<13 dB EbN0 (the practical limit for zero BER)
Tracking rates > 100 deg./sec.
16 simultaneous dual-polarized beams
Error-free bit rates up to 30 Mbps from a flying source (hardware supports 120Mbps)
Optimal (pre-detection) combination
Multipath mitigation due to novel processing approach
A Digital Beam-forming Module (DBM) is a small multi-beam phased- array antenna. It can function as a stand-alone antenna senor, or in cooperation with other DBMs to form a very large antenna aperture. All DBMs within an array communicate through a mesh network and orient themselves as a single aperture capable of simultaneously forming multiple beams.
There is no requirement for DBMs to be installed on a planar surface or as a contiguous array.
A DBM array functions as a coherent antenna aperture and will compare favorably with a 70% efficient dish antenna occupying the same area. RF signals are digitized and processed throughout the antenna aperture. Beam formed, filtered signals are transported as digital signals through the mesh.
The output of the multiple beams are available at the terminus of the mesh, at a host controller. as digital or analog( IF or RF) signals at almost any desired frequency.
Unconventional beam-forming techniques make possible for the DBMs to operate robustly even under sever multi-path conditions.
DBMs afford extreme flexibility for the system designer, placing the angular shape of the gain profile and the frequency coverage into the cost trade-space. DBMs are currently available for individual S-band and L-band operation, and will soon be functioning simultaneously at L& S-band and also at C-band.
We used current-generation low-cost commercially-available hardware to prototype a small-scale array to demonstrate such high performance with the potential for greatly-reduced SWaPC (Size Weight Power & Cost).
Excellent IM3 performance was demonstrated by the distributed digital receiver (an inherent feature of our DBF approach).
The System acquired and tracked 30 Mbps source moving at 120 deg/sec within +/-60 deg. field of view, and was even able to produce an error-free signal while tracking over +/- 90 deg in azimuth and/or elevation, in the presence of multipath.
We continue to develop UBT through our IRAD efforts, particularly in the following dimensions:
Increasing maximum data rate per channel
Increasing maximum aggregate data rate over all channels
Increasing maximum number of simultaneous beams
Reduce the SWAP footprint
Reduce the DBF cost by 3-5x compared to E-9 generation (2008)
Increase the hardware reliability and add fault tolerance
Fabricate flight-qualified production hardware for mission operation
Extend our UBT demonstration platlform from Rx-only to Tx/Rx
Demonstrate applicability of UBT to telemetry, communications and radar
Demonstrate multi-function capability using UBT
Investigate applications of UBT for ground, sea, air and space
Extend UBT to very large arrays