Q: Can you list all the properties of the carrier-smoothing filter?
A: Carrier-smoothing filters, also known as Hatch filters, are commonly used to reduce (“smooth”) the noise and multipath errors in pseudorange measurements by exploiting the high-precision relative distance information from carrier phase measurements. However, carrier-smoothing filters operate on more than just noise and multipath, and this article summarizes the response of such filters to all relevant inputs.
By Inside GNSSThe U.S. stance on satellite navigation has long supported international cooperation and a degree of interoperability. In 2010 the Obama administration even adopted a space policy that said foreign satnav services could be used “to augment and strengthen the resiliency of GPS.”
That was easier in the abstract, however, when the only fully functional GNSS was GPS. Now, with other GNSS services coming online, American officials want to think things through again.
By Dee Ann DivisReporting from Brussels last year, we explained that the then–brand new EU GNSS Regulation had effectively put to bed years of wrangling over who does what in Europe’s GNSS programs. But the issue reared its head again in Brussels recently, in a highly charged discussion hosted by the European Economic and Social Committee (EESC).
By Peter Gutierrez
Return to main article: "Valérie Renaudin: Navigating a Life with GNSS"
COMPASS POINTS
Engineering specialties
Geomatics engineering, design of dynamic position estimation algorithms, GNSS and other sensors, including inertial MEMS, UWB Tx, hybridization filters for navigation, low-cost sensor error modeling and calibration, and magnetic field processing.
By Inside GNSSValérie Renaudin’s Compass Points
Geomatics engineer Valérie Renaudin now directs a major research laboratory in Nantes, France, working on the future of personal navigation and intelligent transportation systems (ITS).
By Inside GNSSWorking Papers explore the technical and scientific themes that underpin GNSS programs and applications. This regular column is coordinated by Prof. Dr.-Ing. Günter Hein, head of Europe’s Galileo Operations and Evolution.
Computational power continues to increase at a rapid pace and unlike other areas of technology, this trend is not expected to slow down in the foreseeable future. Software GNSS receivers fully exploit these developments to steadily increase performance.
By Inside GNSSThe availability of several GNSSes promises advanced positioning, navigation, and timing services with higher availability and improved accuracy. According to a European GNSS Agency (GSA) market study, nearly 60 percent of receivers, chipsets, and modules already support at least two GNSS constellations, showing that multi-constellation is becoming a standard feature across all market segments. That development brings up questions of law and regulation that require careful handling by GNSS manufacturers, service providers, and policy makers.
By Ingo BaumannOne of the first feature articles I wrote as a newly minted GNSS magazine editor 26 years ago was about an advanced rail traffic management system based on GPS that Burlington Northern, with the help of Rockwell Collins, had designed and implemented.
By Inside GNSSQ: Are there special considerations for dealing with raw GNSS data?
A: Most GNSS users are only interested in position, velocity, and/or time (PVT) information provided by a receiver. In fact, most mass-market GNSS receivers (e.g., those in cell phones or in your vehicle) only provide PVT information along with some supporting data (such as the number of satellites tracked, dilution of precision, course over ground, and so forth).
By Inside GNSSWorking Papers explore the technical and scientific themes that underpin GNSS programs and applications. This regular column is coordinated by Prof. Dr.-Ing. Günter Hein, head of Europe’s Galileo Operations and Evolution.
By Inside GNSSAfter three years in Chapter 11, the company whose planned wireless broadband system threatened to overload GPS receivers across the United States is preparing to emerge from bankruptcy.
By Dee Ann Divis