English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Global Navigation Satellite Systems (GNSS) are playing a key role in modern society finding applications in several crucial sectors. Strategic areas of applications include vehicular and personal navigation, aircraft and maritime navigation, location based and rescue services. However, despite its worldwide success and diffusion, GNSS is still a sensitive system vulnerable to failure and disruptions. This is of particular concern for user of safety of life services demanding high reliability, availability and continuity. The disruptions potentially threatening GNSS are usually classified as intentional and unintentional. Intentional disrup‐ tions, such as jamming, spoofing, are produced to deliberately impair GNSS receiver operation. Unintentional disruptions can be man-made interference, for example originating from satellite communications, TV broadcasting and Ultra Wide Band (UWB) communications, and natural interference, due to space weather events. One of the main natural threats to the reliability and availability of GNSS is represented by the non-stationary propagation condi‐ tions experienced by Radio Frequency (RF) signals inside the ionosphere. In particular small scale ionospheric irregular structures may refract and diffract GNSS signals producing random and fast variations in their amplitude and phase [1]. Amplitude scintillation manifests itself as instantaneous increases and decreases of the transionospheric signal intensity. This phenom‐ enon, when severe, can lead to deep signal fading and, consequently, induce the signal to noise ratio to drop below the receiver tracking threshold. Moreover, phase scintillation could increase the Doppler shift so to render it larger than the phase lock loop bandwidth. As a consequence cycle slips or even a loss of lock could occur. Even if this phenomenon usually does not affect all satellites in view at the same time, involving only a portion of the sky, it may be able to degrade the final solution accuracy. Moreover if the healthy satellite links are not enough to provide a solution, outages in the GNSS operation could be experienced. A way to

Kalman Filter Based PLL Robust Against Ionospheric Scintillation