Abstract: One embodiment provides a system that facilitates integrated security and high availability. During operation, the system obtains a number of data elements from a data stream based on a number of coded fragments that a code word includes. The system determines one or more bit-level operations for the data elements in such a way that at least one of the one or more bit-level operations becomes eliminated from a process of erasure encoding. The system then obfuscates the data elements based on one or more bit-level operations. Subsequently, the system generates a code word of the erasure encoding from the obfuscated data elements based on the generator matrix. The code word comprises a plurality of coded fragments.

Abstract: An apparatus comprises an antenna array having N elements to receive N input streams from a plurality of transmitters and a post-processing device to perform a wavefront de-multiplexing transform on the N input streams corresponding to M orthogonal beams to generate M output streams using a weight matrix having M beam weight vectors (BWVs) associated with the M orthogonal beams, where M and N are positive integers and 1<M?N. The M BWVs are calculated using an optimization procedure based on performance constraints. The performance constraints for one of the M orthogonal beams with an orthogonal beam radiation pattern include designated peak and null positions.

Abstract: An apparatus comprises an antenna array having N elements to receive N input streams from a plurality of transmitters and a post-processing device to perform a wavefront de-multiplexing transform on the N input streams corresponding to M orthogonal beams to generate M output streams using a weight matrix having M beam weight vectors (BWVs) associated with the M orthogonal beams, where M and N are positive integers and 1<M?N. The M BWVs are calculated using an optimization procedure based on performance constraints. The performance constraints for one of the M orthogonal beams with an orthogonal beam radiation pattern include designated peak and null positions.

Abstract: A MIMO basestation for a cellular communications system comprises a remote indoor processing facility coupled to an outdoor RF tower via optical fibers. The remote indoor processing facility includes a bank of RF modulators to modulate signal streams; a remote MIMO transmitting processor that includes a remote digital beam-forming network to transform the modulated signal streams into transmit beam signals; a pre-processor to perform a wavefront multiplexing transform on the transmit beam signals to generate wavefront multiplexed beam signals, each of the wavefront multiplexed beam signals being a linear combination of the transmit beam signals; and RF-to-optical drivers to perform optical modulating functions on the wavefront multiplexed beam signals to generate optical waveform streams.

Abstract: A system comprises a ground hub and a mobile airborne platform hovering over or close to a coverage area on or near the earth surface. A bistatic radar receiver on the airborne platform includes a first antenna system to capture reflected radiofrequency signals originated from a satellite via reflected paths from the coverage area; and a second antenna system to transmit the reflected radiofrequency signals to the ground hub via a feeder link. At the ground hub, a multibeam antenna system receives the reflected radiofrequency signals and captures radiation signals directly from the satellite via a direct path; and a remote beam forming network remotely forms receiving beams for the first antenna system. A remote radar processing center includes a cross-correlator to receive the reflected radiofrequency signals and the radiation signals as two input signal streams, perform cross-correlations between the two input signal streams, and output an output signal stream.

Abstract: A communication system includes (1) a first airborne linear array configured to project a first fan beam over a first ground coverage elongated in a first direction, the first fan beam delivering a first information data associated with a first data stream; and (2) a second airborne linear array configured to project a second fan beam over a second ground coverage elongated in a second direction, the second fan beam delivering a second information data associated with a second data stream. The first and second ground coverages are overlapped to form a common coverage area. The first and second data streams are complementary to each other and are linear combinations of a plurality of segmented substreams. The plurality of segmented substreams is formed from an information data stream. The first and second data streams are generated from a ground control facility.

Abstract: An apparatus includes a memory storing a digital envelope and a wavefront demultiplexing (WFD) device which receives M input streams concurrently, M being an integer greater than 1, performs a WFD transformation on the M input streams, and generates M output streams concurrently. A first input stream includes wavefront multiplexed digital identifiers for digital right management. A second input stream is the digital envelope. The first input stream presented in a digital format appears to human perception as having identical features to the digital envelope presented in the digital format. Each output stream is a linear combination of the M input streams such that the digital identifiers are recovered from at least one of the M output streams. The digital envelope is a data file used by a sender to send the M input streams and is scaled with a magnification factor greater than 1 in the WFD transformation.

Abstract: An apparatus comprises a segmenter and a pre-processor. The segmenter segments a first stream of data into P-1 substreams, P being an integer greater than 1. The pre-processor, having N input ports, N being an integer greater than P-1, receives the P-1 substreams at P-1 ports of the N input ports and a second stream at a Pth input port. The pre-processor generates P output streams from the P-1 substreams and the second stream using a P-to-P K-muxing operation. The P output streams are uploaded to a cloud storage via a network. Redundancy of the P output streams recovered by a user from the cloud storage is based on whether the second stream is accessible to the user.

Abstract: For data writing, a first wavefront multiplexing (WFM) processor performs WFM on M input streams to generate N output streams. A pre-processor segments or codes a source stream to produce the M input streams. For data reading, a first wavefront demultiplexing (WFD) processor performs WFD on M input streams to generate N output streams. A post-processor de-segments or decodes the N output streams into a source stream.

Abstract: 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.

Abstract: This device combines multiple elements that function like a single smart antenna that performs both connectivity and spatial discrimination functions. The antenna functions in both receive and transmit modes. The apparatus utilizes commonly used components to distinguish and separate desired satellite signals from those signals of satellites in close directional proximity. Disclosed are six methods for optimizing simultaneously reception of multiple desired satellite signals performed either mechanically or electronically and also included is an optimization technique. The transmission apparatus uses many of the same components as the receiver antenna and additionally uses in-beam nulling to fine tune transmission.

Abstract: For signal transmission, a pre-processing device performs a wavefront multiplexing (WVM) transform on M input streams corresponding to M orthogonal beams to generate N output streams using a weight matrix having M beam weight vectors (BWVs) associated with the M orthogonal beams. An antenna array having N elements transmits the N output streams to a plurality of receivers. For signal reception, an antenna array having N elements receives N input streams from a plurality of transmitters. A post-processing device performs a wavefront de-multiplexing (WVD) transform on the N input streams corresponding to M orthogonal beams to generate M output streams using a weight matrix having M beam weight vectors (BWVs) associated with the M orthogonal beams. M and N are positive integers and 1<M?N. The M BWVs are calculated using an optimization procedure based on performance constraints.

Abstract: An antenna system includes N movable antenna elements configured to generate concurrently M receiving beams pointing respectively at M satellites radiating in a common frequency band, N and M being integers and N?M?2. A beam forming system is coupled to the N movable antenna elements and configured to shape the M receiving beams using weights inputted from a beam controller. The beam controller optimizes the M receiving beams by computing spatial displacements to spatially reposition the N movable antenna elements relative to each other, using an iterative optimization processing to satisfy a plurality of constraints concurrently. A position driver system spatially re-positions the N movable antenna elements in accordance to the spatial displacements inputted from the beam controller.

Abstract: A receiving terminal for communication via NGSO satellites comprises an outdoor unit coupled to an indoor unit via optical fibers. The outdoor unit comprises an array antenna for capturing signals from the satellites; low-noise amplifiers; analog-to-digital conversion blocks for converting the captured signals to digital signals; a pre-processor for performing a wavefront multiplexing transform on the digital signals and generating wavefront multiplexed signals; and RF-to-optical drivers for transforming the wavefront multiplexed signals to optical waveforms.

Abstract: A communications system between a source and a destination includes a transmitter at the source and a communication connectivity. The transmitter comprises a preprocessor and a candidate envelope folder to provide M known a priori digital envelopes, M?1. The preprocessor has N input ports and N output ports, N>M, performs at least one wavefront multiplexing (WFM) transform on N inputs received at the N input ports to generate N outputs at the N output ports. The preprocessor performs the at least one WFM transform by calculating, for each of the N outputs, a linear combination of the N inputs using one of the M digital envelopes such that a digital format of one of the N outputs appears to human sensors as having features substantially identical to a digital format of the one of the M digital envelopes.

Abstract: An apparatus includes a memory storing a digital envelope and a wavefront demultiplexing (WFD) device which receives M input streams concurrently, M being an integer greater than 1, performs a WFD transformation on the M input streams, and generates M output streams concurrently. A first input stream includes wavefront multiplexed digital identifiers for digital right management. A second input stream is the digital envelope. The first input stream presented in a digital format appears to human perception as having identical features to the digital envelope presented in the digital format. Each output stream is a linear combination of the M input streams such that the digital identifiers are recovered from at least one of the M output streams. The digital envelope is a data file used by a sender to send the M input streams and is scaled with a magnification factor greater than 1 in the WFD transformation.

Abstract: An antenna system comprises: multiple antenna elements; and multiple beam forming networks configured to produce radiation patterns for both receiving and transmission functions configured to be optimized by re-positioning said antenna elements, wherein said beam forming networks comprise a receiving beam forming network configured to combine multiple first inputs from said antenna elements into at least a first output, and a transmission beam forming network configured to divide a second input into multiple second outputs to said antenna elements.

Abstract: A retro-directive antenna system on a mobile airborne platform for communication with a ground hub located within a coverage area. The system comprises an antenna array, a receive beamforming network, and a diagnostic processor. The antenna array comprises a plurality of antenna elements. The receive beamforming network generates concurrently a plurality of receive beams for the respective antenna elements. The receive beams correspond to respective beam positions within the coverage area. A first beam position points to the ground hub and a corresponding receive beam receives a target signal from the ground hub. The diagnostic processor determines a best position for the first beam position based on a ranking system and controls the receive beamforming network by updating the beam positions based on the best position for the first beam position.

Abstract: One embodiment provides a system that facilitates numerical operation-based erasure coding. During operation, the system determines the bit-width of processing capability of the computing system. The system then determines, based on the bit-width, a number of bits for representing a respective data element from a data stream and a number of data elements based on a number of a dimension of a generator matrix of erasure encoding. The system then obtains the number of data elements from the data stream and converts a respective obtained data element to a corresponding numerical representation. Here, a respective obtained data element is represented by the determined number of bits. The system then generates a code word, which comprises a plurality of coded fragments, of erasure encoding from the numerical representations based on the generator matrix of the erasure encoding.

Abstract: Enveloping techniques using incoherent wavefront multiplexing (WF muxing or K-muxing) will enhance privacy protection on data communications. The disclosure relates to methods and architectures of packing or enveloping data using WF muxing, or K-muxing, for information transport via multiple communication links such as concurrently via multiple satellites, airborne platforms, wireless terrestrial links, and/or other wireless links. The multi-link communications may include the use of cloud transport of multiple WF-muxed data packages. It is focused to appearance of a digital envelop and reliability of enclosed data. The K-muxing on information digital streams before modulation in a transmitter shall provide enhanced data privacy and better availability. The WF multiplexed (WF muxed or K-muxed) information data streams will be individually and concurrently sent to the multiple links accordingly for data transport.