3com Corporation

L-3 Communications Corporation

S5 Wireless, Inc.

Recon Dynamics, LLC

Other

L3 Technologies, Inc.

3com Cororation

Sy Prestwich

Jeffrey L Jones

Scott Bevan

Dirk Ostermiller

Jeffrey B Bench

David C Andrus

W Kurt Dobson

Steven Lo Forte

Richard Alan McNamee

Kurt Stewart

David Moore

James R Baker

Brent Delbert Madsen

David D Oliphant

Thomas A Johnson

Ryan A Kunz

Scott M Lyon

Michael C Hollenbeck

John Wheeler

K Deric Eldredge

John Marshall

John M Wheeler

David Carter

Michael B Hollenbeck

Steven LoForte

A mainlobe detection process can include a number of tests that are performed to define when the monopulse antenna system will transition from open loop scanning to closed loop scanning and then to tracking. A hybrid tracking technique is also provided which adaptively discovers and corrects for phase alignment error. Magnitude-only tracking can be performed initially to locate the nulls in the azimuth and elevation ratios and to identify the magnitudes of these ratios at these nulls. Phase tracking can be then performed. During phase tracking, phase corrections can be repeatedly applied to the azimuth and elevation difference channels to correct any phase error that may exist. During this process, the magnitudes of the ratios can be used to determine how the phase corrections should be adjusted. Once the hybrid tracking process is complete, the monopulse antenna system is properly phase-aligned and phase tracking will be correctly employed.

Adaptive discovery and correction of phase alignment errors in monopulse antenna systems

A monopulse antenna system can include a monopulse detector assembly (MDA) that is configured to steer a monopulse antenna based on the magnitude of an elevation ratio or azimuth ratio independently of the phase of the ratio. To prevent the direction of the monopulse antenna from being changed too frequently, the MDA can employ ratio bins to determine when the direction of the monopulse antenna should be reversed. Also, the MDA may enforce a hold period during which a change in the direction of the monopulse antenna will not be performed. The MDA can employ one or more mapping equations to generate a steering signal as a function of the magnitude of the ratio. The mapping equations can be selectively employed based on whether tracking is being performed at or near the ratio null.

Phase agnostic monopulse tracking

A monopulse tracker includes multiple dual-axis monopulse antenna systems that are angled with respect to one another. The orientations of the monopulse antenna systems create a much larger field of view for the monopulse tracker to eliminate the need to steer the monopulse tracker. The monopulse tracker can be configured to estimate a position of an object based on tracking information received from more than one monopulse antenna system therefore increasing the accuracy of the estimated position. The multiple monopulse antenna systems can be arranged in a low-profile housing to facilitate use of the monopulse tracker on aircraft.

Low-profile monopulse tracker

Mainlobe detection process for monopulse antenna systems

Systems and method for detecting and removing an arbitrary phase difference between a sum channel signal and a difference channel signal in a monopulse system. A sum channel signal is received from a sum channel signal source and a difference channel signal is received from a difference channel signal source. The difference channel signal is shifted according to various potential arbitrary phase differences &#x3c6;and &#x3c6;+&#x3c0; (where &#x3c6;is from 0 to &#x3c0; radians, i=0, 1, . . . , n; &#x3c6;+&#x3c0; going from &#x3c0; to 2&#x3c0; radians) between the sum and difference channel signals to thereby generate difference channel signals each having a different phase. The difference channels having a different phase are combined with the sum channel signal to generate a plurality of sum+difference signals and sum&#x2212;difference signals. Based on the plurality of sum+difference signals and sum&#x2212;difference signals, maximum in-phase and out-of-phase correlations are determined from the &#x3c6;and &#x3c6;+&#x3c0; pairs. The maximum in-phase and out-of-phase correlation pairs are used in an error estimate calculation.

Monopulse arbitrary phase detection and removal

A radio frequency (RF) receiver system that is configured to achieve high dynamic range may include at least one antenna and a plurality of receivers connected to the at least one antenna. The plurality of antennas may be configured to provide different gains. The RF receiver system may include an analog-to-digital (A/D) converter subsystem connected to the plurality of receivers. The A/D converter subsystem may include a plurality of A/D converters. An overall digitization range of the A/D converter subsystem may be greater than a digitization range of any of the plurality of A/D converters individually. The overall digitization range of the A/D converter subsystem may be sufficiently large so as to accommodate a desired dynamic range of the RF receiver system.

Radio frequency receiver systems that are configured to achieve high dynamic range

A wide area location and telemetry system may include a wide area location and telemetry system server that is configured to determine wide area location and telemetry system data about an object when the object is located within the coverage area of the wide area location and telemetry system. The wide area location and telemetry system server may also be configured to receive localized location and telemetry system data about the object when the object is located within the coverage area of a localized location and telemetry system. The wide area location and telemetry system may also include a database and a database manager. The database manager may be configured to store the wide area location and telemetry system data and the localized location and telemetry system data in the database.

Systems and methods for obtaining and using data from a localized location and telemetry system in a wide area location and telemetry system

A device for site monitoring is disclosed. The device may include a communication interface configured to receive site monitoring data from a site monitoring system. The communication interface may also be configured to wirelessly transmit the site monitoring data to a base station. The site monitoring data may include a device identification. The device also may include a processor and memory. The memory also may include two pseudonoise (PN) codes, namely a first PN code and a second PN code. The site monitoring data may be received from the site monitoring system. The site monitoring data may be spread using the first PN code to provide first spread site monitoring data. The first spread site monitoring data may be spread using the second PN code to provide second spread site monitoring data. The second spread site monitoring data may be transmitted using a burst direct sequence spread spectrum radio signal.

Burst spread spectrum radio system and method for site monitoring

A system for wireless asset tracking is disclosed. The system includes a plurality of mobile devices. Each mobile device performs two spreading operations with two distinct PN codes, a first PN code and a second PN code. Data is transmitted by each mobile device using a burst direct sequence spread spectrum radio signal. The system also includes at least three base stations. Each base station is configured to receive the burst direct sequence spread spectrum radio signals from the mobile devices which includes decoding the signals by first de-spreading with the second PN code and second de-spreading with the first PN code. Each base station is further configured to add a timestamp to each data packet received. A system for calculating the location of the mobile devices creates location information for each mobile device by calculating the time difference of arrival of received bursts for each base station.

Burst spread spectrum radio system and method for asset tracking and data telemetry

A spread spectrum communications system using long, scalable PN sequences to achieve variable communication rates using a low-complexity and scalable matched filter architecture to provide a large processing gain, robust recovery of multiple devices in long reach, high ambient-noise environments.

Matched filter for scalable spread spectrum communications systems

A transmitter for a spread spectrum communications system may include a data source, a first multiplier/mixer spreading data from said data source with a first pseudo noise source, a second multiplier/mixer spreading data from said first mixer with a second pseudo noise source, and an RF transmitter. A receiver for a spread spectrum communications system may include an RF receiver, a first matched filter receiving data from said RF receiver, a plurality of phase/frequency shifters receiving a signal from said first matched filter, a plurality of second matched filters receiving data from said plurality of phase/frequency shifters, and an equalizer/decoder receiving signals from said plurality of second matched filters.

A spread spectrum communications system adapted to receive simultaneous signals from multiple transmitters, separates frequency error and equalizes and decodes continuous streams of data sets from a plurality of matched filters with frequency correction and which sorts through data and successfully decodes data bits. The spread spectrum communications system includes a transmitter and a receiver. The receiver includes an RF receiver. At least one PNB matched filter receives signals from the RF receiver. A plurality of frequency shifters receives a signal from the at least one PNB matched filter. A plurality of PNA matched filters receives data from the at least one PNB matched filter and the plurality of frequency shifters. An equalizer/decoder receives signals from the plurality of PNA matched filters.

Equalizer with decision feedback frequency tracking and bit decoding for spread spectrum communications

A spread spectrum communications system uses long, scalable PN sequences to achieve variable communication rates. A low-complexity and scalable matched filter architecture is used to provide a large processing gain and robust recovery of multiple devices in long reach, high ambient-noise environments. The spread spectrum communications system includes a transmitter and a receiver. The receiver includes an RF receiver and a first matched filter receiving data from the RF receiver. A plurality of phase/frequency shifters receives a signal from the first matched filter. A plurality of second matched filters receive data from the plurality of phase/frequency shifters. An equalizer/decoder receives signals from the plurality of phase/frequency shifters.

An integrated diversity antenna solution is presented that positions multiple antennas within the digital device case. The integrated diversity antenna solution works equally well with diversity radios, such as 802.11, and non-diversity radios, such as Bluetooth. The non-diversity radios are supported via a power splitter attached to the antennas that give the necessary directional coverage. The integrated antenna array solves the main problem associated with wireless communication on laptop computers, specifically, that laptops perturb the radiation pattern because of the influence that laptop components have on standard antennas and the presence of interfering objects, most notably the laptop user, in the surrounding environment.

Growing community of inventors

Riverton, UT, United States of America

Sy Prestwich