The electromagnetic spectrum is a core strategic resource of modern information systems. As the physical-layer foundation of spectrum cognition， a high-performance wideband RF receiving platform directly bounds the performance ceiling of subsequent sensing and cognition algorithms through its front-end hardware performance. This paper presents a highly integrated software-defined radio platform for spectrum cognition applications based on radio frequency system-on-chip （RFSoC） technology， integrating Gsps-class high-speed AD/DA converters， FPGA programmable logic， multi-core ARM processors， DDR4 high-capacity memory， and diversified high-speed peripheral interfaces onto a single 150 mm×100 mm board. A systematic RF receiving performance evaluation is conducted via a direct signal-source connection method， covering key dimensions including basic receiving parameters， ADC core dynamic performance， and dynamic range with sensitivity. Experimental results demonstrate that the platform supports a maximum receiving frequency of 4 GHz， maintains an effective number of bits （ENOB） of 7.97—8.32 bits， achieves a noise spectral density better than -151 dBFS/Hz， and delivers a system dynamic range exceeding 71 dB. With its comprehensive advantages in high integration density， wide instantaneous bandwidth， and diversified high-speed interfaces， the platform offers an effective hardware foundation for spectrum cognition intelligence.