Dynamic spectrum access supported by a lowlatency wireless sensor network for spectrum usage monitoring is demonstrated using OpenAirInterface platform. The platform performs secondary communications in bands detected as free, thanks to its multi-band capability. With respect to application scenarios, the main target is to address agile broadband public safety communications. Firstly, this demonstration will highlight the newest hardware platforms offered by OpenAirInterface comprising the ExpressMIMO baseband engine and the AgileRF front-end. The second aspect of the demonstration aims to highlight OpenAirInterface's performance evaluation methodology allowing for scalable emulated real-time deployment of radio networks on generic PC-based computers.