To address the challenges in deploying 50G passive optical network(PON) systems-including the 32 dB power budget requirement, compatibility of 25 Gb/s and 50 Gb/s upstream rates, and coexistence with existing GPON and 10G PON systems，a real-time 50G PON system supporting high-power budget and multi-rate compatibility is proposed. The system introduces low-frequency envelope amplitude modulation in the laser to effectively suppress fiber nonlinear effects caused by high-power transmission. At the optical line terminal(OLT) receiver, dynamic adaptive optical digital signal processing(oDSP) technology collaboratively working with the multi-access control (MAC) layer achieves compatibility for 25 Gb/s and 50 Gb/s upstream rates. Additionally, spatial optical hybrid wavelength-division multiplexing technology enables coexistence of 50G PON with GPON and 10G PON on the same PON port. The experimental results show that the system achieves a 32 dB power budget, meeting the C+ standard. Without additional pilot overhead, 50G PON can coexist and operate collaboratively with existing GPON and 10G PON systems on the same port.