This paper analyzes the practical application requirements of high-precision and high-reliability relative positioning technology in complex environments, and on this basis, the technology of Beidou multi-frequency multi-path real-time detection, perfect enhancement relative positioning reliable monitoring is studied. The multi-objective cooperative relative positioning principle system is constructed, and the preliminary experimental verification is carried out in combination with the application direction and scene, and the relatie positioning ability of multi-dynamic target, real-time high precision and high reliability is verified.