Multibeam GNSS antenna based on flatten Luneburg lens

High accuracy Global Navigation Satellite System (GNSS) refers to the use of advanced technology and techniques to improve the precision and accuracy of position, navigation, and timing information typically in centimeter or subcentimeter level, which is suitable for various applications such as surveying, agriculture, autonomous vehicles and more. Antenna requirements for high-accuracy GNSS applications are typically more demanding than those for general purpose GNSS, they include high gain to capture the weak signals emitted by the satellites, wide band to capture the signals from multiple GNSS frequency channels, multipath rejection and Low phase center variation. A Luneburg lens is a type of spherical lens that has a gradual variation of refractive index from the center to the edge [1]. This property makes it suitable for use in a multi-beam GNSS antenna, as it can focus multiple beams toward different satellite signals simultaneously. Recently, several flatten Luneburg lens solution for millimeter waves have been proposed to provide a wide angle of view using a planar antenna configuration [1-3]. The lens shape and refractive index distribution cause the beams from the antenna elements to converge at different points in space, creating multiple beams that can be directed towards different satellites. The extension of flatten Luneburg lens is the main objective of the work. This allows the antenna to track multiple satellites at once, improving the accuracy and reliability of the GNSS signal. The lens will be 3D printed targeting a peak directivity higher than 16dBi in L band and a 150°scanning range.