Antennas play a more important role than ever in IoT equipped with modernized GNSS receivers. Conventionally, the key metrics for assessing the GNSS antenna performance is generally characterized by efficiency/efficacy, gain, the overall signal carrier-to-noise ratio and user domain solution errors. At the component level, once satisfactory performance is achieved on the antenna design, it passes onto the next system-level of applications. Many discrete GNSS antennas are sold in the market in this approach and leave it to the design engineers to determine how the input impedance, standing wave ratio, and reflection coefficient versus frequency are associated with the rest of the sub-circuitries.
Nowadays, the GNSS is simply one among several RF systems in a radio cohabitation environment – a mix that includes new added GNSS frequencies and non-GNSS signals such as cellular or Wi-Fi. A new requirements-level assessment is required to determine that the GNSS antenna performance can be accomplished within both physical constraints (e.g., size, budget, and weight) and operational environment for an intended application.
