Modern Improvements of GNSS Technologies: New Opportunities in Exploration of the Earth’s Ionosphere

Today, we have a novel, promising tool to improve the sensitivity and quality of the remote probing of the ionosphere by Global Navigation Satellite Systems (GNSS) signals. Modern GNSS receivers used for studying the ionosphere provide carrier phase measurements with a temporal resolution of up to 100 Hz. Modern GNSS satellites broadcast many different signal components (L1L, L2L, L5Q, et al.) at L1, L2, and L5 frequency bands. It provides a huge set of satellite signals registered with high temporal resolution. Such a global and high-precision tool to explore the ionosphere greatly improves the performance of GNSS-based remote probing technologies and provides an opportunity to detect the weakest ionospheric turbulences and waves in the ionosphere. The chapter contains a review of new research results, methods, and ideas, allowing us to utilize the modern improvements of GNSS technologies for deep and highly effective studies of the ionosphere.