Abstract: Apparatus and associated methods relate to providing robust synchronization of a Radio-Frequency (RF) communication in a severe-fading environment. A first portion of a detected RF signal is auto-correlated with a second portion of the detected RF signal. The first and second portions are time-separated by the predetermined time delay separating the first and second code-sequences. A third portion of the detected RF signal is sync-correlated with a sync-sequence so as to generate a sync-correlation signal. The third portion is of the predetermined length of the sync sequence and includes the first and second portions of the detected RF signal used to generate the auto-correlation signal. The auto-correlation signal is multiplied by the sync-correlation signal so as to generate a combined synchronization signal. A peak in the combined synchronization signal is then detected. This peak can be indicative of a synchronization time of an authorized communication.

Abstract: A system includes one or more radio frequency (RF) emitters configured to transmit RF energy into a specified area in order to inactivate one or more specified microorganisms in the specified area. The system also includes a control system configured to control the one or more RF emitters in order to adjust the RF energy transmitted by the one or more RF emitters. The control system is configured to obtain information identifying different types of microorganisms that are or might be present in the specified area over time and to adjust the RF energy transmitted by the one or more RF emitters in order to target the different types of microorganisms for inactivation over time.

Abstract: Apparatus and associated methods relate to providing robust synchronization of a Radio-Frequency (RF) communication in a severe-fading environment. A first portion of a detected RF signal is auto-correlated with a second portion of the detected RF signal. The first and second portions are time-separated by the predetermined time delay separating the first and second code-sequences. A third portion of the detected RF signal is sync-correlated with a sync-sequence so as to generate a sync-correlation signal. The third portion is of the predetermined length of the sync sequence and includes the first and second portions of the detected RF signal used to generate the auto-correlation signal. The auto-correlation signal is multiplied by the sync-correlation signal so as to generate a combined synchronization signal. A peak in the combined synchronization signal is then detected. This peak can be indicative of a synchronization time of an authorized communication.

Abstract: A system includes one or more radio frequency (RF) emitters configured to transmit RF energy into a specified area in order to inactivate one or more specified microorganisms in the specified area. The system also includes a control system configured to control the one or more RF emitters in order to adjust the RF energy transmitted by the one or more RF emitters. The control system is configured to obtain information identifying different types of microorganisms that are or might be present in the specified area over time and to adjust the RF energy transmitted by the one or more RF emitters in order to target the different types of microorganisms for inactivation over time.

Abstract: An optical feed network (OFN) for an RF phased antenna array includes a single free-space optical beamformer that supports all of the RF electrical feed signals for the RF phased antenna array to steer an RF beam. The free-space optical beamformer can more easily scale to accommodate larger array sizes than either the discrete fiber channel or PIC implementations. Furthermore, certain embodiments of the optical beamformer avoid the complexity of having to compute FFTs for each channel to steer the beam, instead relying on the inherent function of an imaging lens to perform the FFT, which in turn facilitates rapid steering.

Abstract: An optical feed network (OFN) for an RF phased antenna array includes a single free-space optical beamformer that supports all of the RF electrical feed signals for the RF phased antenna array to steer an RF beam. The free-space optical beamformer can more easily scale to accommodate larger array sizes than either the discrete fiber channel or PIC implementations. Furthermore, certain embodiments of the optical beamformer avoid the complexity of having to compute FFTs for each channel to steer the beam, instead relying on the inherent function of an imaging lens to perform the FFT, which in turn facilitates rapid steering.

Abstract: A method of generating a transmit signal by a transmitter for transmission to a receiver includes receiving input data, generating a base symbol signal, the base symbol signal, generating a perturbation signal based on the input data, and combining the base symbol signal and the perturbation signal to generate the transmit signal.

Abstract: A coupler for separable physically coupling together a pair of objects includes two parts, on opposite sides of a boundary, that have different piezoelectric characteristics. When an electric field is applied to the coupler parts the piezoelectric forces induce a mechanical stress that separates the parts. The parts may be made of the same or a similar material, such as a suitable ceramic material, with the different piezoelectric characteristics produced by templating the parts with different domain orientations, from different seeds, for example using a three-dimensional manufacturing processes. The coupler may be used to allow shock-free (or reduced shock) separation of parts, such as separation of stages of vehicles such as flight vehicles.

Abstract: A coupler for separable physically coupling together a pair of objects includes two parts, on opposite sides of a boundary, that have different piezoelectric characteristics. When an electric field is applied to the coupler parts the piezoelectric forces induce a mechanical stress that separates the parts. The parts may be made of the same or a similar material, such as a suitable ceramic material, with the different piezoelectric characteristics produced by templating the parts with different domain orientations, from different seeds, for example using a three-dimensional manufacturing processes. The coupler may be used to allow shock-free (or reduced shock) separation of parts, such as separation of stages of vehicles such as flight vehicles.

Abstract: A sensor system and method of reducing plasma-induced communication inhibition for a main antenna includes using auxiliary antennas for detecting a density of plasma that affects operation of the main antenna, and re-orienting an electromagnetic field around the main antenna in response to the density detected to reduce effect of the plasma on the main antenna. The auxiliary antennas are also operable for data link communication and switchable such if the density of the plasma inhibits receipt or sending of signals by one of the auxiliary antennas, another one of the auxiliary antennas may be used for data link communication.

Abstract: A sensor system and method of reducing plasma-induced communication inhibition for a main antenna includes using auxiliary antennas for detecting a density of plasma that affects operation of the main antenna, and re-orienting an electromagnetic field around the main antenna in response to the density detected to reduce effect of the plasma on the main antenna. The auxiliary antennas are also operable for data link communication and switchable such if the density of the plasma inhibits receipt or sending of signals by one of the auxiliary antennas, another one of the auxiliary antennas may be used for data link communication.

Abstract: In one aspect, a method includes performing a mapping on bits to form a complex data symbol, applying a frequency rotation mask to the complex data symbol based on a polynomial phase, performing an inverse discrete Fourier transform (IDFT) after applying the frequency rotation mask, applying a time domain window after performing the IDFT, converting digital data to analog data after applying the time window and transmitting the analog data as an analog signal.

Abstract: In one aspect, a method includes performing a mapping on bits to form a complex data symbol, applying a frequency rotation mask to the complex data symbol based on a polynomial phase, performing an inverse discrete Fourier transform (IDFT) after applying the frequency rotation mask, applying a time domain window after performing the IDFT, converting digital data to analog data after applying the time window and transmitting the analog data as an analog signal.

Abstract: Embodiments of a spread-carrier self-detecting code (SCSDC) receiver with summed-delay processing (SDP) and method are generally described herein. In some embodiments, the SCSDC-SDP receiver is arranged to generate a chip-matched filter output from a received spread-spectrum signal and perform SDP on the chip-matched filter output with a plurality of delay-processing chains. The SDP may include multiplying a conjugated and delayed chip-matched filter output with the chip-matched filter output and applying a code-matched filter that is matched to a delay-multiplied code. The outputs from the code-matched filters of each delay-processing chain may be coherently combined to provide an output having correlation peaks for use generating frequency error and timing information.

Abstract: In accordance with the present invention, a method of processing a signal is described that includes receiving a signal having an encoded digital packet, wherein the digital packet includes packet data and a packet frame, wherein the packet frame includes a common digital signal that is common to each one of a plurality of digital packets. The method further includes sampling a signal associated with the received signal to provide a sampled signal. The method further includes performing a channel characterization by contrasting a signal representative of the sampled signal with a signal representative of the common digital signal. A corresponding system is also described.

Abstract: Embodiments of a spread-earner self-detecting code (SCSDC) receiver with summed-delay processing (SDP) and method are generally described herein. In some embodiments, the SCSDC-SDP receiver is arranged to generate a chip-matched filter output from a received spread-spectrum signal and perform SDP on the chip-matched filter output with a plurality of delay-processing chains. The SDP may include multiplying a conjugated and delayed chip-matched filter output with the chip-matched filter output and applying a code-matched filter that is matched to a delay-multiplied code. The outputs from the code-matched filters of each delay-processing chain may be coherently combined to provide an output having correlation peaks for use generating frequency error and timing information.

Abstract: In accordance with the present invention, a method of processing a signal is described that includes receiving a signal having an encoded digital packet, wherein the digital packet includes packet data and a packet frame, wherein the packet frame includes a common digital signal that is common to each one of a plurality of digital packets. The method further includes sampling a signal associated with the received signal to provide a sampled signal. The method further includes performing a channel characterization by contrasting a signal representative of the sampled signal with a signal representative of the common digital signal. A corresponding system is also described.

Abstract: In accordance with the present invention, a method of processing a signal is described that includes receiving a signal having an encoded digital packet, wherein the digital packet includes packet data and a packet frame, wherein the packet frame includes a common digital signal that is common to each one of a plurality of digital packets. The method further includes sampling a signal associated with the received signal to provide a sampled signal. The method further includes performing a channel characterization by contrasting a signal representative of the sampled signal with a signal representative of the common digital signal. A corresponding system is also described.

Abstract: A transmitter, receiver and communication technique. The transmitter is adapted to interleave a first pseudo-noise sequence with a second pseudo-noise sequence to provide a third pseudo-noise sequence. The third sequence is transmitted and then received by the inventive receiver. The first and second sequences are chosen so that an XOR of the two sequences produces a third, known-valid pseudo-noise sequence. The receiver includes an arrangement for receiving and correlating the third pseudo-noise sequence to provide a measure of a frequency of the transmitted signal. The receiver further includes an arrangement for downconverting and filtering the received signal to provide a filtered complex signal. A complex multiplier is included for effecting a complex multiplication of the filtered complex signal with a delayed version of the filtered complex signal to provide a product. A correlator is included for correlating the product to provide the measure of frequency.

Abstract: A transmitter, receiver and communication technique. The transmitter is adapted to interleave a first pseudo-noise sequence with a second pseudo-noise sequence to provide a third pseudo-noise sequence. The third sequence is transmitted and then received by the inventive receiver. The first and second sequences are chosen so that an XOR of the two sequences produces a third, known-valid pseudo-noise sequence. The receiver includes an arrangement for receiving and correlating the third pseudo-noise sequence to provide a measure of a frequency of the transmitted signal. The receiver further includes an arrangement for downconverting and filtering the received signal to provide a filtered complex signal. A complex multiplier is included for effecting a complex multiplication of the filtered complex signal with a delayed version of the filtered complex signal to provide a product. The delayed version of the filtered signal is delayed by a chip period.