The SRX project aims to develop an industrial prototype of a multi-GNSS multi-frequency GNSS receiver module, offering high-precision positioning and heading capability in adverse signal environments like forests. The usage of Galileo E5ab and BeiDou-3 B2 ACE-BOC wide-band signals integrated with MEMS sensor measurements is considered a key here to achieve robust vector tracking based solutions for reliable high-precision PNT. Usage of the latest state-of-the-art HW innovations in RF-ASICs, digital processor SoC, MEMS and clock technology are considered essential to ensure a long-term availability of the product. Processing scalability to cover the increasing number of GNSS satellites in orbit and processing flexibility to enable implementation of very complex signal and navigation processing algorithms are keys for a successful system design. But the heart of the system is a sophisticated RTK enabled vector-tracking algorithmic solution, being beyond the state-of-the-art. Suited HW and algorithmic prototyping form an essential part of the project to minimize the related development risks.