A communications system includes a ground hub, mobile airborne platforms, and a user terminal. The ground hub includes an antenna system, a beam-forming system and a baseband processor. The antenna system receives return-link signals radiated respectively by the mobile airborne platforms. The return-link signals correspond to signal streams transmitted by the user terminal and received by the mobile airborne platforms. The signal streams correspond to data streams including a known pilot code stream. The beam-forming system forms beams to receive the return-link signals and transforms the received return-link signals into baseband signals. The baseband processor includes adaptive equalizers to equalize the baseband signals and a wavefront demultiplexing processor to perform a wavefront demultiplexing transform on the equalized baseband signals to produce recovered versions of the data streams.