Uncategorized Archives - Page 24 of 82 - Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design

Evaluating the Performance of Navigation Payloads

As a navigation satellite transmits multiple signals on single frequency (e.g., Open Service and Restricted Service over L5 Band), these are combined on a common carrier to comprise a composite signal. This composite signal passes through navigation payload subsystems such as an up-converter, traveling wave tube amplifier (TWTA), filters, and so on. These subsystems may introduce adverse effects on the signal, such as amplitude and phase distortion, nonlinear effects, gain imbalance, IQ imbalance, and phase noise.

By Inside GNSS

Tracking IRNSS Satellites

The Indian Regional Navigation Satellite System (IRNSS)] is designed as a stand-alone regional navigation system with a primary service area extending up to 1,500 kilometers from the Indian land mass. Finland lies north of 60°N latitude more than 5,000 kilometers away from India, as shown in Figure 1 (see photo at the top of this article).

By Inside GNSS

Higher Aspirations for GNSS

New space missions such as the robotic repair and recovery of damaged or errant communication satellites may become possible with the aid of an emerging class of receivers that is able to use GPS signals for navigation in orbits thousands of kilometers above the middle Earth orbit (MEO) GPS constellation itself.

By Dee Ann Divis

What are the actual performances of GNSS positioning using smartphone technology?

Q: What are the actual performances of GNSS positioning using smartphone technology?

A: “Where I am?” is the typical question asked by a person when visiting a new city or unknown place. Knowing one’s own location is generally a basic necessity for people, both in indoors and outdoors.

By Inside GNSS

Multi-GNSS Precise Positioning

The availability of carrier phase tracking — counting the cycles of GNSS signals between satellites and a receiver — has long enabled high-precision users to achieve greater accuracy than using the navigation messages or pseudoranges. Improvements in high-end receivers and techniques such as real-time kinematic (RTK) and precise point positioning (PPP) have made once inconceivably accurate results almost routinely accessible.

By Inside GNSS

MEOSAR: New GNSS Role in Search & Rescue

Working 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.

SIDEBAR: Locating a Distress Beacon Activated in Flight

By Inside GNSS