Innovation

Innovation: Reducing the Jitters

May 1, 2014By
AtomicClockChip-O2

How a Chip-Scale Atomic Clock Can Help Mitigate Broadband Interference
Small low-power atomic clocks can enhance the performance of GPS receivers in a number of ways, including enhanced code-acquisition capability that precise long-term timing allows. And, it turns out, such clocks can effectively mitigate wideband radio frequency interference coming from GPS jammers. We learn how in this month’s column. read more

Innovation: Ground-Based Augmentation

April 2, 2014By
FIGURE 5. Research aircraft D-IBUF (Dornier Do 128-6).

Combining Galileo with GPS and GLONASS
While a GPS-based GBAS will offer improved navigation services for aircraft, might these services be even better if the systems were to use satellites from other constellations besides GPS? In this month’s column, the authors show how GBAS protocols might be modified to accommodate multiple constellations, offering results of preliminary tests using GPS, GLONASS, and Galileo simultaneously. read more

This article is tagged with , and posted in Aviation, Design & Test, From the Magazine, Innovation, Receiver Design

Innovation: A PET Project from Finland

March 1, 2014By
FIGURE 1. Block schematic of the AutoPET assembly.

Automating GNSS Receiver Testing
In this month’s column, the authors discuss an automated test bench for analyzing the overall performance of multi-frequency multi-constellation GNSS receivers. read more

Innovation: Ionospheric Modeling Using GPS

February 1, 2014By
FIGURE 2. The network of the four stations used in the evaluation procedures.

Greater Fidelity Using a 3D Approach
In this month’s column we look at the performance of a 3D approach to modeling the ionosphere, including times when the ionosphere is particularly interesting (read disturbed). read more

This article is tagged with and posted in Algorithms & Methods, From the Magazine, Innovation

Innovation: Cycle Slips

January 1, 2014By
FIGURE 1. A cycle slip affecting phase measurements but not the pseudoranges.

Detection and Correction Using Inertial Aiding
A team of university researchers has developed a technique combining GPS receivers with an inexpensive inertial measuring unit to detect and repair cycle slips with the potential to operate in real time. read more

Innovation: Hunting for GNSS Echoes

November 1, 2013By
Figure 1. ARTEMISA simulation platform architecture.

Analysis of Signal Tracking Techniques for Multipath Mitigation
Researchers involved with ARTEMISA describe their efforts to generate synthetic multipath of GPS L1 and Galileo E1 signals and to test different signal tracking techniques in a simulated receiver to see which techniques best minimize the effects of multipath on positioning solutions. read more

This article is tagged with , and posted in Algorithms & Methods, Innovation

Innovation: Getting Closer to Everywhere

October 1, 2013By
FIGURE 1. Functional flow diagrams for a strapdown inertial navigation system (top) and a pedestrian dead-reckoning system (bottom).

Accurately Tracking Smartphones Indoors
If we wish to obtain consistently usable positions indoors using a mobile phone, we can augment its GPS or GNSS receiver with other unfettered sensing technologies such as gyroscopes and accelerometers supplemented by radio signals of opportunity. But is all of this actually feasible? The authors have conducted tests of a multi-system approach to positioning indoors with favorable results. read more

This article is tagged with , , and posted in Indoor Positioning, Innovation, Mobile, Tracking

Innovation: Under Cover

September 1, 2013By
FIGURE 1. Artist’s impression of the synthetic-aperture GNSS system for surveying in a forest.

Synthetic-Aperture GNSS Signal Processing
We take a look at a novel GNSS signal-processing technique, which uses the principles of SAR to improve code and carrier-phase observations in degraded environments such as under forest canopy. The technique can simultaneously reject multipath signals while maximizing the direct line-of-sight signal power from a satellite. Along with a specially programmed software receiver, it uses either a single conventional antenna mounted, say, on a pedestrian’s backpack for GIS applications or a special rotating antenna for high-accuracy surveying. Want to learn more? Read on. read more

This article is tagged with , , and posted in Algorithms & Methods, From the Magazine, Innovation