US 10,892,819 B2
Multi-channel communications system using mobile airborne platforms
Donald C. D. Chang, Thousand Oaks, CA (US)
Assigned to SPATIAL DIGITAL SYSTEMS, INC., Camarillo, CA (US)
Filed by SPATIAL DIGITAL SYSTEMS, INC., Agoura Hills, CA (US)
Filed on Jul. 22, 2019, as Appl. No. 16/518,969.
Application 16/518,969 is a continuation of application No. 15/457,701, filed on Mar. 13, 2017, granted, now 10,361,775.
Application 15/457,701 is a continuation of application No. 13/778,171, filed on Feb. 27, 2013, granted, now 9,596,024, issued on Mar. 14, 2017.
Prior Publication US 2019/0363784 A1, Nov. 28, 2019
Int. Cl. H04B 7/204 (2006.01); H04B 7/208 (2006.01); H04W 4/90 (2018.01); H04B 7/06 (2006.01); H04B 7/185 (2006.01); H04W 24/02 (2009.01); H04W 72/06 (2009.01)
CPC H04B 7/2041 (2013.01) [H04B 7/0617 (2013.01); H04B 7/18504 (2013.01); H04B 7/208 (2013.01); H04W 4/90 (2018.02); H04W 24/02 (2013.01); H04W 72/06 (2013.01); H04B 7/0639 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A communications system comprising:
a ground hub comprising:
a first antenna system configured to receive return-link signals radiated respectively by a plurality of mobile airborne platforms, the return-link signals corresponding to first signal streams transmitted by a user terminal and received by the mobile airborne platforms, the first signal streams corresponding to first data streams including a known pilot code stream;
a beam-forming system coupled to the first antenna system, configured to form beams to receive the return-link signals and transform the received return-link signals into baseband signals; and
a baseband processor coupled to the beam-forming system, comprising:
adaptive equalizers configured to equalize the baseband signals and output equalized baseband signals; and
a wavefront demultiplexing processor configured to perform a wavefront demultiplexing transform on the equalized baseband signals and output second data streams as recovered versions of the first data streams, a first one of the second data streams being a recovered version of the known pilot code stream.