System and method for wave vector multiplexed laser communication

Wave vector division multiplexing ("WVDM") is a method of free-space multiplexing for optical communications. In WVDM, wave vectors of individual laser beams are manipulated so that each individual laser beam has a unique wave vector. These individual laser beams are multiplexed into an aggregate beam, which is transmitted to a receiver. The receiver separates the individual laser beams on the basis of their unique wave vectors. One area where WVDM is useful is in quantum cryptography. WVDM can also be combined with traditional wavelength division multiplexing ("WDM") to increase throughput even further.

System and method for audio hot spotting

Audio hot spotting is accomplished by specifying query criterion to include a non-lexical audio cue. The non-lexical audio cue can be, e.g., speech rate, laughter, applause, vocal effort, speaker change or any combination thereof. The query criterion is retrieved from an audio portion of a file. A segment of the file containing the query criterion can be provided to a user. The duration of the provided segment can be specified by the user along with the files to be searched. A list of detections of the query criterion within the file can also be provided to the user. Searches can be refined by the query criterion additionally including a lexical audio-cue. A keyword index of topic terms contained in the file can also be provided to the user.

Voice signature with strong binding

Voice signature method. The signer obtains a public key from an intended recipient of a document to be electronically signed. The signer speaks a personal identification number (PIN) to generate a voice PIN and the signer also speaks at least the signer's name. The voice PIN and voice signature are appended to the document and the voice PIN is encrypted using the public key to create an encrypted voice PIN. A polynomial hash is generated based on the document, the voice signature and the encrypted voice PIN and this hash is itself encrypted based on the PIN to generate an encrypted hash. Finally, the document, the voice signature, the encrypted voice PIN and the encrypted hash are sent to the intended recipient.

High-quality detection based on sequential interference cancellation techniques

The present invention relates to a system and method for successive interference cancellation in a multi-user wireless communication system. In one aspect of the invention, a method of decoding signals from a plurality of superimposed signals is provided. In an embodiment, the plurality of superimposed signals are ranked in order of signal strength. The strongest signal is then decoded and a signal estimate thereof generated and subtracted from the plurality of superposition signals. The method repeats iteratively, decoding and canceling the strongest signal, until all signals are decoded. In another aspect of the invention, a system for decoding signals from a plurality of superimposed signals is provided. In an embodiment, the system is a wireless multi-user receiver.

Auto-configuration of spectrum use by wireless pre-planned or ad hoc networks

A method of, and a wireless device capable of, dynamically allocating radio spectrum access within a wireless communication system includes a wireless transceiver having at least a physical layer functionality to transmit and receive data across a wireless network. The device extracts measurements of radio spectrum conditions from a least one of a local and a remote wireless transceiver to form an assessment of radio spectrum conditions. The device then integrates the assessment of radio spectrum conditions to form an integrated assessment of radio spectrum conditions between the local and remote wireless transceivers. The device further possesses a means for selecting a preferred set of radio spectrum access parameters for a communications session between the local and remote wireless transceiver.

Spreading code derived from weil sequences

Methods and systems relating to Weil-based spreading codes are described herein. In an embodiment, a method includes generating a set of Weil sequences, adapting a plurality of sequences of the set of Weil sequences to form a first plurality of codes, and selecting a second plurality of codes from the first plurality of codes. A code of the first plurality of codes is selected based at least on a correlation associated with the code. Each code of the first plurality of codes has a predetermined length.

System and method for interference cancellation with multi-stage multi-user detection

Reduction of multiple access interference, in one example for asynchronous CDMA systems using long codes. In one aspect, parallel interference cancellation (PIC) implements a decoupled estimate, preferably non-linear and applied at chip intervals. According to another aspect, interference is cancelled using a technique that estimates bits for a symbol by interpolating signature waveforms for users to a common sampling lattice of the received data. According to another aspect, multi-stage, hybrid multi-stage, and reconfigurable recursive multi-stage multi-user detection architectures and corresponding processes are provided.

Sub-symbol parallel interference cancellation

Reduction of multiple access interference, in one example for asynchronous CDMA systems using long codes. In one aspect, parallel interference cancellation (PIC) implements a decoupled estimate, preferably non-linear and applied at chip intervals. According to another aspect, interference is cancelled using a technique that estimates bits for a symbol by interpolating signature waveforms for users to a common sampling lattice of the received data. According to another aspect, multi-stage, hybrid multi-stage, and reconfigurable recursive multi-stage multi-user detection architectures and corresponding processes are provided.