Scientific Drilling International, Inc.

Samsung Electronics Co., Ltd.

Rx Networks Inc.

Fathom Systems Inc.

Mohamed Youssef

Matthew A White

Ashkan Izadpanah

Brian Daniel Gleason

Timothy Whitacre

Guylain Roy-Machabee

Bruce McCullough

Andi Jakupi

Brett H Van Steenwyk

Tim Whitacre

Steven A Gronemeyer

Brian Gleason

Muhammad Haris Afzal

Behnam Aminian

William Stewart

A method may include providing one or more telemetry transmission systems, the one or more transmission systems comprising one or more receivers and one or more transmitters. The method may also include transmitting a first synchronization sequence from the one or more telemetry transmission systems, the first synchronization sequence transmitted in a first channel, and the first synchronization sequence being at least a portion of a first telemetry signal. In addition, the method may include transmitting a second synchronization sequence the one or more telemetry transmission systems, the second synchronization sequence transmitted in a second channel, and the second synchronization sequence being at least a portion of a second telemetry signal. The first and second synchronization sequences may be transmitted simultaneously or at a predetermined time difference. The method may include receiving the first synchronization sequence at the one or more receivers, and receiving the second synchronization sequence at the one or more receivers.

Collaborative telemetry

A method for transmitting data from a MWD system at the BHA of a drill string may include transmitting the data in a MWD signal from the MWD system. The MWD signal may be modulated at a position closer to the surface onto a mud pulse modulated signal. The mud pulse modulated signal may be generated by a downhole friction reducing device. The downhole friction reducing device may include a mud motor. The mud motor may create pressure pulses based on its speed of rotation. The downhole friction reducing device may include a modulating valve. The modulating valve may be electromechanically or mechanically operated. The modulated signal may be detected at the surface by a receiver using one or more pressure or flow sensors. The receiver may use one or more harmonics of the modulated signal to receive the data.

Downhole MWD signal enhancement, tracking, and decoding

A method of determining a location of a mobile device includes: detecting, at the mobile device, at least one Radio Frequency transmitter; receiving information associated with a number of Radio Frequency transmitters located within a geographical area, the number of Radio Frequency transmitters being a subset of all Radio Frequency transmitters located within the geographical area, the information being decodable to provide global locations and identifiers of the number of Radio Frequency transmitters; comparing an identifier associated with the at least one detected Radio Frequency transmitter with the global locations and identifiers of the number of Radio Frequency transmitters; and determining the location of the mobile device within the geographical area; wherein the information is received in a reduced format.

Geo-reference based positioning of a mobile device

A method of determining a position of a GNSS receiver includes: receiving, at the GNSS receiver, information from at least two GNSS satellites and an estimated location area from a non-GNSS positioning application, determining candidate pseudoranges corresponding to candidate correlation peaks determined based on the information received from the at least two GNSS satellites; determining possible positions of the GNSS receiver using the candidate pseudoranges and the estimated location area; determining a best possible position of the GNSS receiver from the possible positions; and setting the best possible position as the position of the GNSS receiver; wherein when multiple candidate correlation peaks corresponding to one of the at least two GNSS satellites are determined, the estimated location area is usable to reduce the number of candidate correlation peaks prior to candidate pseudoranges being determined.

Method and apparatus for determining a position of a GNSS receiver

Methods, systems, and portable devices capable of adaptive synthetic positioning while in a dead zone are described. In one method, when a portable device having a Global Navigational Satellite System (GNSS) receiver and a dead zone database enters a dead zone, it determines whether the dead zone database has a record for the dead zone. If it does, it retrieves parameters corresponding to the dead zone from the database and calculates synthetic position solutions using the retrieved parameters while in the dead zone. The portable device may also use the synthetic position solutions to help calculate position solutions when exiting the dead zone. If a dead zone database record does not exist, the portable device determines parameters for calculating synthetic position solutions in the dead zone and a new dead zone database record indicating a set of parameters based on the determined set of parameters is created.

Adaptive synthetic positioning

A method of determining a location of a mobile device includes: detecting, at the mobile device, at least one Radio Frequency transmitter; receiving information associated with a number of Radio Frequency transmitters located within a geographical, area, the number of Radio Frequency transmitters being a subset of all Radio Frequency transmitters located within the geographical area, the information being decodable to provide global locations and identifiers of the number of Radio Frequency transmitters; comparing an identifier associated with the at least one detected Radio Frequency transmitter with the global locations and identifiers of the number of Radio Frequency transmitters; and determining the location of the mobile device within the geographical area; wherein the information is received in a reduced format.

A method for soft frame synchronization in a navigational receiver is provided. A distance between bits of a sync pattern received by the navigational receiver and a known sync pattern is computed. A probability of detection value for the received sync pattern based on the distance is assigned. A confidence level for the received sync pattern using the probability of detection value is computed. The confidence level is compared with a confidence threshold. If the confidence level is greater than or equal to the confidence threshold, the confidence level of the received sync pattern is updated to generate a credibility of the sync pattern. The credibility of the received sync pattern is compared with a predetermined credibility value and, if the credibility of the received sync pattern is greater than or equal to the predetermined credibility value, synchronization of the navigational receiver is performed using the received sync pattern.

Method and apparatus for frame synchronization in a positioning system

Methods, systems, and apparatuses for a portable device capable of receiving satellite navigational system signals to retrieve visibility mask information corresponding to the portable device's current location and/or trajectory are described.

Growing community of inventors

Marion, IA, United States of America

Mohamed Youssef