Low cost system and method for making dual band GPS measurements

US6570534B2 · kind B2 · utility

Assignee

• INTEGRINAUTICS CORPORATION · US

Inventors

• Clark E. Cohen · Washington, US
• David G. Lawrence · Santa Clara, US
• Stewart Cobb · Palo Alto, US
• Paul Montgomery · Menlo Park, US
• Miro Samek · Palo Alto, US
• Kurt R. Zimmerman · Mountain View, US
• Michael L. O'Connor · Redwood City, US
• Walter Melton · Columbia, US
• Gregory M. Gutt · Ashburn, US

Key dates

• Filing date: Feb 5, 2002
• Grant date: May 27, 2003
• Expiry date: Feb 5, 2022

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S19/44
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A low-cost, solid-state position sensor system suitable for making precise code and carrier phase measurements in the L1 and L2 bands of GPS uses an ordinary, low-cost OEM card single-frequency carrier phase tracking C/A code receiver and includes low-cost hardware for sensing the L1 and L2 components of GPS carrier phase. Such measurements are suitable for general use in a variety of fields, including surveying. They are also of sufficient quality to be used in controlling heavy machinery, such as aircraft, farm tractors, and construction and mining equipment. A C/A code continuous tracking GPS receiver is used to produce GPS positioning fixes and real-time L1 carrier phase measurements. This C/A code receiver generates timing and reference information for a digital sampling component. This sampling component processes the L1 and L2 signals from the GPS signals in view. A digital signal processing component coupled to this sampling component processes the raw samples in synchronous, batch form including a step to precisely unwrap the P(Y) carrier phase to baseband. The receiver outputs synchronous, carrier phase measurements associated with each ranging source and signal observabl…