Innovation

Innovation: Software GNSS Receiver

September 1, 2012By
Fig9

An Answer for Precise Positioning Research
In this month’s “Innovation,” we look into the development and capabilities of one modern software GNSS receiver in an effort to answer the question “What is the ideal GNSS receiver for precise positioning research?” read more

This article is tagged with and posted in From the Magazine, Innovation, Manufacturing, Receiver Design

Innovation: The Devil Is in the Details

July 1, 2012By
FIGURE 4. A CPSE observed on SVN48 (PRN07) on September 15, 2010, at 19:21:42 GPS Time. (Click to enlarge.)

Looking Closely at Received GPS Carrier Phase
The stability of a received GPS signal determines how well the receiver can track the signal and the accuracy of the positioning results it provides. While the satellites use a very stable oscillator and modulation system to generate their signals, just how stable are the resulting phase-modulated carriers? In particular, do received signals always conform to the published system specifications? In this month’s column we take a look at a specially designed receiver for analyzing GPS carrier phase and some of the interesting results that have been obtained. read more

This article is tagged with and posted in From the Magazine, GNSS, Innovation, Signal Processing

Innovation: Coming Soon

June 1, 2012By
FIGURE 1. GNSS tracking stations in the IGS real-time network.

The International GNSS Real-Time Service
The International GNSS Service has embarked on a project to provide a high-accuracy GPS satellite orbit and clock data service in real time. The service will also provide 1-Hz data streams of GPS and GLONASS data from a network of global continuously operating reference stations. The IGS real-time data and orbit and clock products will be of immense benefit for geoscience studies and a host of other science and engineering applications. A team of authors associated with this project discusses the genesis and status of the real-time service and the plans to provide an initial operating capability. read more

This article is tagged with and posted in Augmentation & Assistance, From the Magazine, GNSS, Innovation

Innovation: Simulating GPS Signals

May 1, 2012By
FIGURE 3. Signal Architect simulation flow. (Click to enlarge.)

It Doesn't Have to Be Expensive
GNSS signal simulators can be expensive and beyond the limited budgets of many researchers. In this month’s column, we look at one company’s approach to providing GNSS signal simulation at a low cost — one that virtually any researcher can afford.GNSS signal simulators can be expensive and beyond the limited budgets of many researchers. In this month’s column, we look at one company’s approach to providing GNSS signal simulation at a low cost — one that virtually any researcher can afford. read more

Innovation: Ionospheric Scintillations

April 1, 2012By
FIGURE 1 Global occurrence characteristics of scintillation. (Figure courtesy of P. Kintner)

How Irregularities in Electron Density Perturb Satellite Navigation Systems
In this month’s column, the international Satellite-Based Augmentation Systems Ionospheric Working Group presents an abridged version of their recently completed white paper on the effect of ionospheric scintillations on GNSS and the associated augmentation systems. read more

Innovation: GNSS Antennas and Humans

February 1, 2012By
FIGURE 6. Gain pattern of the patch antenna as measured by the measured C/N0 at all elevation angles as a function of antenna distance from body. Elevation angles [0º, 90º] have azimuths [180º, 360º], while elevation angles [90º, 180º] have azimuths [0º, 180º].

A Study of Their Interactions
A team of researchers from The University of Calgary report on tests conducted on two different types of GPS antennas operated in the vicinity of a human phantom — an artificial body with similar electromagnetic properties as that of a real human. read more

This article is tagged with , and posted in From the Magazine, GNSS, Innovation, OEM

Innovation: Know Your Enemy

January 1, 2012By
Inno-Opener

Signal Characteristics of Civil GPS Jammers
GPS jamming is a continuing threat. A detailed understanding of how the available jammers work is necessary to judge their effectiveness and limitations. A team of researchers from Cornell University and the University of Texas at Austin reports on their analyses of the signal properties of 18 commercially available GPS jammers. read more

Innovation: Digging into GPS Integrity

November 1, 2011By
Inn-opener

Charting the Evolution of Signal-in-Space Performance by Data Mining 400,000,000 Navigation Messages
There are four important requirements of any navigation system: accuracy, availability, continuity, and integrity. In this month’s column we take a look at one particular aspect of GPS integrity: that of the signal in space and find out how trustworthy is the satellite ephemeris and clock information in the broadcast navigation message. read more

This article is tagged with , and posted in From the Magazine, GNSS, Innovation, Signal Processing