Harris Corporation

Harris Global Communications, Inc.

Michael Andrew Wadsworth

John Wesley Nieto

William Nelson Furman

James Anthony Norris

Brian Padalino

Brent Josefiak

Thomas Gerard Kenney

Charles Allen Linn

A method for compressing a short message includes receiving a short message that includes a plurality of text strings for compression, dividing the short message into one or more sub-blocks, where a number of text strings in each of the one or more sub-blocks is less than or equal to a predetermined number. The method also includes compressing each of the one or more sub-blocks by identifying a type of a first text string, identifying a code representing the type, determining whether the first text string exists in a library, upon determining that the first text string exists in the library, determining an index corresponding to the first text string, extracting a predetermined number of least significant digits of the index, and replacing the first text string in that sub-block with the code and the extracted predetermined number of least significant digits of the index.

Efficient short message compression

Systems () and methods for reducing a number of cyclostationary features in a transmitted signal. The methods comprise: obtaining by a transmitter a discrete-time IF signal comprising a sequence of samples all having a same sample duration; performing operations by a sub-sample dithering processing device of the transmitter to modify a sample timing of the discrete-time IF signal by decreasing or increasing a duration of at least one first sample of the sequence using a digital signal processing technique in a digital domain; converting the discrete-time IF signal to an RF signal; and transmitting the RF signal having a reduced number of cyclo stationary features.

Application of transmit sub-sample dithering apparatus for cyclostationary feature elimination

Systems () and methods for removing dither introduced into a transmitted RF signal. The method comprising: receiving, by a receiver, the transmitted RF signal; converting, by the receiver, the transmitted RF signal into a discrete-time IF signal comprising a sequence of samples, where at least a first sample of said samples has a first sample duration different than a second sample duration of at least a second sample of said samples; and performing operations by a sub-sample dither removal device of the receiver to modify a sample timing of the discrete-time IF signal by decreasing or increasing the first sample duration of the first sample using a digital signal processing technique in a digital domain.

Systems and methods for cyclostationary feature elimination

The digital video communications device includes a scalable video coding (SVC) controller including an encoder and associated block equalizer. The encoder is configured to receive digital video, and encode received digital video into a plurality of related streams including a base layer having a first modulation type, and scaled enhancement layers having different modulation types. The block equalizer is configured to generate a waveform by sequentially interleaving the plurality of related streams with equalizer probes. The digital video transmission approach allows the receiver to automatically provide the best video quality that the channel will support without negotiation with the transmitter.

Systems and methods for multiple stream encoded digital video

A communications system may include a first communications device that may include a transmitter and a modulator cooperating therewith to modulate a coded waveform using a constant phase modulation (CPM) to generate a non-linear CPM waveform, and generate a linear representation of the non-linear CPM waveform, the linear representation including a plurality of pulses. The transmitter and a modulator may further cooperate to remove at least some of the plurality of pulses to define a modified linear representation of the non-linear CPM waveform, and transmit the modified linear representation of the non-linear CPM waveform. The communications system may further include a second communications device that may include a receiver and a single pulse-matched filter linear demodulator cooperating therewith to demodulate the modified linear representation of the non-linear CPM waveform transmitted from the first communications device.

Modified continuous phase modulation communications system and related methods

A communication system includes a plurality of nodes forming a wireless mesh network. A plurality of wireless communication links connect the nodes together. Each node is formed as a communications device having a physical layer and a media access control (MAC) layer in accordance with the Open System Interconnect (OSI) model and operative for transmitting and receiving communications packets to and from other nodes via the wireless communication links in an Automatic Repeat Request (ARQ) mode. The physical layer monitors channel parameters of the wireless communications link when in an ARQ mode and, based on the channel parameters, communicates to the MAC layer over-the-air (OTA) parameters used for transmitting packets.

Automatic repeat request (ARQ) communication system using physical layer monitoring

A system communicates data and includes an encoder for encoding communications data with a forward error correction code. A data randomizer randomizes the communications data with a random bit sequence and a combining circuit combines the communications data with known symbols into frames. A modulator maps the communications data into minimum shift keying or Gaussian minimum shift keying (MSK or GMSK) symbols based on a specific mapping algorithm to form a communications signal having an MSK or GMSK waveform over which the communications data can be transmitted.

System and method for communicating data using constant amplitude equalized waveform

A wireless communications device may include a wireless receiver for receiving signals comprising alternating known and unknown symbol portions, and a demodulator connected thereto. The demodulator may include a channel estimation module for generating respective channel estimates for a prior unknown symbol portion(s), current unknown symbol portion and for future unknown symbol portion(s). An autocorrelation module may generate autocorrelation matrices for the prior, current and future unknown symbol portions. A channel match filter module may generate respective channel matching coefficients for the prior and current/future unknown symbol portions, and a factorization module may divide the autocorrelation matrices into respective upper and lower autocorrelation matrices. A transformation module may transform the channel matching coefficients into upper and lower channel matching coefficients. A a back-substitution module may determine the current unknown symbol portion based upon the upper and lower autocorrelation matrices and channel matching coefficients for the current and prior/future unknown symbol portions.

Wireless communications device performing block equalization based upon prior, current and/or future autocorrelation matrix estimates and related methods

A wireless communications device may include a wireless receiver receiving signals having alternating known and unknown symbol portions over a channel, and a demodulator systolic array. The demodulator systolic array may include a channel estimation module generating respective channel estimates for each unknown symbol portion based upon the known symbol portions. An autocorrelation module may generate autocorrelation matrices based upon the channel estimates. A channel match filter module may generate respective channel matching coefficients for the unknown symbol portions, and a factorization module may divide the autocorrelation matrices into respective upper and lower autocorrelation matrices. A transformation module may transform the channel matching coefficients into upper and lower channel matching coefficients. A back-substitution module may determine the unknown symbol portions by estimating the unknown symbol portions based upon autocorrelation matrices and channel matching coefficients, lower autocorrelation matrices and channel matching coefficients, and combining the estimates.

Wireless communications device providing enhanced block equalization and related methods

A communications system of the present invention includes a transmitter that is operative for combining an orthogonal Walsh modulation with a minimum shift keying or Gaussian minimum shift keying waveform to form a hybrid communications signal that carries communications data over a constant amplitude waveform that is spread in time and frequency. This communications signal can be transmitted to a RAKE receiver that has a plurality of correlators with output weights formed for processing this hybrid communications signal.

System and method for communicating data using constant amplitude waveform with hybrid orthogonal and MSK or GMSK modulation

A device and method for controlling HF single side band radio squelch operation in which a serial tone burst indicates the start and end of a transmission and identifies an on-going transmission. Additionally, receivers in a power saving sleep mode can be activated by receipt of a set of serial tone bursts that have been transmitted with sufficient duration for the receiver to be assured the opportunity to detect them. During the subsequent transmission of information, single 'keep-alive' serial tone bursts are transmitted at random time intervals. The end of a transmission is signalled by another set of serial tone bursts. The bursts are provided with the transmitted signal on its frequency and preserve signal bandwidth.

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Palmyra, NY, United States of America

Michael Andrew Wadsworth