Harris Corporation

Smartsky Networks, LLC

Christopher Douglas Moffatt

John Erich Hoffmann

Kevin Carl Gustke

James G Tonti

Ray J Kolar

Charles W Richards

Anders S Mattsson

Thomas Jay Billhartz

G Patrick Martin

John E Hoffman

Travis Lee Berrier

Richard David Lilley

John W Pajunen

Carlos G Abascal

David M Browning

Gary J Headley

Richard D Lilley

James Tonti

An air-to-ground communications system includes at least one base station to be positioned on the ground and including a ground-based transceiver, a phased array antenna coupled to the ground-based transceiver, and a beamforming network coupled to the ground-based transceiver. The ground-based transceiver is configured to provide data traffic and control information to an aircraft. The beamforming network is configured to simultaneously generate at least one narrow antenna beam for the data traffic and at least one wide beam for the control information.

Terrestrial based air-to-ground communications system and related methods

A communications device may include a transmit path, a receive path operable simultaneously with the transmit path and at a same frequency as the transmit path, and processing circuitry. The processing circuitry may be configured to generate a baseband signal for the transmit path, generate a feedforward signal based upon the baseband signal, and use the feedforward signal to reduce self-interference in the receive path from the transmit path.

Communications device with simultaneous transmit and receive and related methods

A communications device may include a wireless receiver, and a processor coupled to the wireless receiver. The processor may be configured to receive a spread OFDM signal having narrowband interference associated with the same, the spread OFDM signal having subcarriers with data distributed among the subcarriers. The processor may be configured to excise the narrowband interference from the spread OFDM signal, and despread the spread OFDM signal after excising and based upon the excising to recover the data.

Communication system with narrowband interference mitigation and related methods

The wireless detection beacon is for use with a Radio Frequency (RF) interrogator transmitting at a first frequency and receiving at a second frequency. The wireless detection beacon includes a substrate, a power supply carried by the substrate, an antenna assembly carried by the substrate, and a local oscillator (LO) carried by the substrate and configured to be powered by the power supply to provide an LO signal at a third frequency. A mixer is carried by the substrate and coupled to the antenna assembly and the LO. The mixer is configured to generate an outgoing beacon signal to the antenna assembly at the second frequency based upon mixing an incoming signal from the RF interrogator at the first frequency with the LO signal at the third frequency.

Wireless location detection and/or tracking device and associated methods

A wireless ranging system for determining a range of a remote wireless device may include a wireless transmitter and a wireless receiver. The wireless ranging system may also include a ranging controller to cooperate with the wireless transmitter and receiver to generate a multi-carrier base waveform, transmit a sounder waveform to the remote wireless device including concatenated copies of the multi-carrier base waveform, and receive a return waveform from the remote wireless device in response to the sounder waveform. The ranging controller may also generate time domain samples from the return waveform, convert the time domain samples into frequency domain data, and process the frequency domain data to determine the range of the remote wireless device.

Wireless ranging system and related methods

The present disclosure presents a predictive signal producing method that effectively levels transmitter output power in a multi-carrier communication system and results in approaching amplifier performance normally associated with constant carrier waveforms. Embodiments of the disclosed solution offers &#x3e;10 dB reduction in the peak-to-average power required to support the transmission of, for example, orthogonal frequency division modulation ('OFDM') modulation techniques. Embodiments of the novel system and method maximize peak-to-average power ratio ('PAPR') reduction with selective mapping and soft clipping, which may include filtering, combined. This novel approach also minimizes overhead, bit error rate, retransmissions, and increases latency as well as implementing processing cycles with a number of iterations. The disclosed system and method improves the total system DC power efficiency and provides an optimal solution for PAPR reduction in multi-carrier communication systems such as, for example, OFDM.

System and method for reducing peak-to-average power ratio for multi-carrier communication systems

A system communicates data and includes a transmitter for transmitting a communications signal that carries communications data. It includes an efficient modulator for approximating the frequencies of sine/cosine basis waveforms using complex exponential functions and adding and subtracting the complex exponential functions to generate an Orthogonal Frequency Division Multiplexed (OFDM) communications signal as a plurality of N data subcarriers that carry communications data as data symbols. A receiver receives the OFDM communications signal and includes a demodulation circuit for demodulating the OFDM communications signal using logical shifts of multiples +/&#x2212;2based on complex exponential functions corresponding to sine/cosine basis waveform approximations to extract amplitude and phase values from a plurality of N data subcarriers as data symbols within the OFDM communications signal.

System and method for communicating data using efficient fast fourier transform (FFT) for orthogonal frequency division multiplexing (OFDM)

A communications device includes a signal input that receives an orthogonal frequency division multiplexed (OFDM) communications signal. A demodulator is connected to the signal input for receiving the OFDM communications signal and demodulating the OFDM communication signal. It includes at least one memory element for storing the at least one sine/cosine basis waveform approximation as complex exponential functions. A logic circuit performs logical shifts in additions and multiples of +/&#x2212;2and extracts amplitude and phase values from a plurality of N data subcarriers within the OFDM communications signal. The demodulator includes efficient implementation of the FFT for use as an OFDM demodulator where the complex exponentials are approximated by multi-level complex sinusoids and optionally oversampled to increase SNR of the FFT output.

System and method for communicating data using efficient fast fourier transform (FFT) for orthogonal frequency division multiplexing (OFDM) demodulation

A communications device includes at least one memory device for storing complex exponential functions as approximations of sine and cosine basis waveforms. A logic circuit adds and subtracts the complex exponential functions to generate an Orthogonal Frequency Division Multiplexed (OFDM) communications signal as a plurality of N data subcarriers that carry communications data. The logic circuit provides efficient and accurate implementation of the IFFT for use as an OFDM modulator using additions of stored complex exponentials and modulation of the integer-valued QAM data symbols using logic shifts and sign changes (2's complement).

System and method for communicating data using efficient fast fourier transform (FFT) for orthogonal frequency division multiplexing (OFDM) modulation

A communications device includes a demapping and demodulation circuit that demaps and demodulates an OFDM communications signal as modulated subcarriers carrying communications data and modulated subcarriers carrying a training sequence forming a preamble that includes a long sync sequence for channel and frequency offset estimation having a extended guard interval (GI). The OFDM subcarriers carrying the training sequence have a quadratic modulation to produce a low peak-to-average power (PAPR) preamble with PAPR of approximately 2.6 decibels (dB). A channel estimate circuit is positioned to receive signals after processing within a FFT circuit and subcarrier demapper circuit and estimates the channel characteristics of the communications channel based on splitting the extended guard interval from the long sync sequence and processing into values that represent the low PAPR preamble as plus or minus one (+/&#x2212;1) values in a real or imaginary component as adds and subtracts.

Orthogonal frequency division multiplexing (OFDM) communications device and method that incorporates low PAPR preamble and receiver channel estimate circuit

A communications device includes communications data and a training sequence corresponding to a preamble. A modulation and mapping circuit modulates the communications data and training sequence into a plurality of multiple subcarriers that are orthogonal to each other to form an OFDM communication signal having modulated subcarriers carrying the communications data forming a data payload and modulated subcarriers forming the preamble. A circuit turns OFF and ON selected subcarriers based on an encryption algorithm to increase transmit power and signal-to-noise ratio and reduce the Inter-Carrier Interference (ICI). The modulation and mapping circuit applies a quadratic modulation to the subcarriers carrying the training sequences to produce a low peak-to-average power ratio (PAPR) preamble with a PAPR value of approximately 2.6 decibels (dB).

Orthogonal frequency division multiplexing (OFDM) communications device and method that incorporates low PAPR preamble and variable number of OFDM subcarriers

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Palm Bay, FL, United States of America

Christopher Douglas Moffatt