Harris Corporation

Flash Comm, Inc.

Albert D Darby, Jr

Donald K Belcher

Rodney L Nelson

Andrew T Powshok

Jeffrey R White

Brendan T Fitzgerald

James Leroy Snell

Raymond F Cobb

Alexander J Nadler

Lamar G McBryde

A data transmission system in which an on/off keyed (OOK) AM/DPSK modulated data signal with an on/off ratio exceeding about 80 dB which has been modulated on a carrier is received at a compact, easily fabricated and battery powered data receiver which operates without automatic gain control and which includes a double loop antenna (diameter of about two inches) with a trimmer capacitor center tapped to the antenna for providing a conjugate impedance match between the antenna and a low noise amplifier. In the receiver, a square-law detection AM demodulator for demodulating the amplified signal is in a bipolar silicon IC, and a DPSK data detector for decoding the demodulated signal is in a separate digital CMOS IC.

Fully integrated data receiver and method for receiving on/off keyed

A two-way communications system that provides ubiquitous wireless data communication services, such as throughout the continental United States, by using a network of only a few, widely distributed radio base station (RBS) sites and the existing paging network infrastructure. The paging network infrastructure is used as an outbound link to request data from the remote field units. The outbound page message indicates a time and frequency at which the RBSs can expect to receive data from the field units. A network hub or message operations center (MOC) coordinates the operation of the paging systems and RBSs from a central location. For example, the MOC determines an available HF frequency and time for a particular field unit to transmit, and then issues the request for data to the field unit using the existing paging network infrastructure. The field units make use of paging receivers, and an HF transmitter to report remote data such as a geoposition or other sensor data when requested to do so.

Low cost wide area network for data communication using outbound message

A two-way communications system provides ubiquitous wireless data communication services, such as throughout the continental United States, by using a network of only a few, widely distributed radio base station (RBS) sites and the existing paging network infrastructure. A network hub or mission operation center (MOC) coordinates the operation of the paging systems and RBSs from a central location. The paging network infrastructure is used as an outbound link over which each of the field units is regularly provided with a outbound data message containing information on the available frequencies and time slots the field units can use to transmit inbound data messages to the RBSs. If any of the field units desires to transmit data to MOC, the field unit selects an available frequency from the outbound data message, and transmits its data at the selected available frequency and time. At least one of the RBSs will receive the inbound message and route it to the MOC which then sends an outbound acknowledgment message, via the paging network, to the field unit which sent the inbound message.

Remote initiated messaging apparatus and method in a two way wireless

A two-way communications system that provides ubiquitous wireless data communication services, such as throughout the continental United States, by using a network of only a few, widely distributed radio base station (RBS) sites and the existing paging network infrastructure. The paging network infrastructure is used as an outbound link to request data from the remote field units. The outbound page message indicates a time and HF frequency at which the RBSs can expect to receive inbound data from the field units. A network hub or mission operation center (MOC) determines a radio frequency which is expected to be propagating and clear at the time that a particular field unit is to use the frequency as an inbound link. The MOC then issues the request for data to the field unit using an existing inexpensive wireless system such as the paging network infrastructure. The field units make use of paging receivers, and an HF transmitter to report remote data such as a geoposition or other sensor data when requested to do so.

Technique for determining propagating and clear frequency to be used in

A method and system for determining whether a transmitting unit is proximate a receiving unit wherein the transmitting unit includes a magnetic field generator for a providing a plurality of time-sequential magnetic fields, each of the sequences being a differential phase shift key (DPSK) modulated code. The magnetic field is transmitted at a relatively interference free frequency of 72 KHz and the DPSK modulation frequency is about 1200 bits per second. Each pair of transmitting and receiving unit uses with a distinguishing code selected from a predetermined group of generally orthogonal codes.

Proximity detection using DPSK waveform

In a communication system, a signal detection and acquisition system, which is capable of locating and phase-locking onto a narrow-band signal in a large frequency uncertainty region in a short period of time, employs the following series of operations:

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Valkaria, FL, United States of America

Albert D Darby, Jr