Technical Article

A Fresh Look at GNSS Anti-Jamming

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GNSS is the technology of choice in most applications due to its dedicated infrastructure, Earth coverage, medium to high accuracy, and large market penetration. Most of the applications, including those we download on our smartphones, are in the category of Location Based Services (LBS). However, there are many other services and businesses that rely heavily on GNSS performance and reliability. For instance, Intelligent Transportation Systems (ITS) make extensive use of GNSS technology and this dependence will only grow in the future.

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By Inside GNSS
November 13, 2016

Satellite Selection

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The advent of multiple constellations provides the opportunity to eliminate geometry weakness as a source of satellite-based augmentation system (SBAS) unavailability. GPS users occasionally encounter areas where an insufficient density of satellites exists to support all desired operations. This most often occurs when a primary slot satellite is out of service. However, adding one or more constellations easily compensates for this geometric shortcoming. In fact, we may now experience the opposite problem of having more satellites that can be tracked by a receiver.

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By Inside GNSS

Navigating in Space

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Spacecraft in low Earth orbit (LEO), at altitudes below 3,000 kilometers, remain within the main Global Positioning System (GPS) signals’ Earth coverage. Spacecraft employing GPS at these altitudes enjoy signal availability and navigation and timing performance emulating that of terrestrial users.

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By Inside GNSS
September 1, 2016

The Particular Importance of Galileo E6C

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The Galileo E6 signal is centered at 1278.75 MHz, and comprises three signals: an authorized signal (E6A, the publicly regulated service, PRS plus two civilian signals), a data component (E6B), and a pilot component (E6C). Both E6B and C are modulated using binary-phase shift keying (BPSK) code division multiple access (CDMA) memory codes, having lengths of 5,115 chips and chipping rates of 5.115 Mcps.

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By Inside GNSS
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