Over on YouTube Dr. Diep N. Nguyen has posted a video showing work done to create a Real Time spectrum database by his team at University of Technology Sydney. The project involves the use of multiple RTL-SDR dongles and Android mobile devices to monitor the spectrum and make it accessible to requestors in real time. They write:

In view of the escalating demand for higher mobile data (from IoT, industry 4.0 applications), there is a growing world-wide interest to improve the radio spectrum utilization. Effective management of the wireless spectrum requires knowledge of the available bandwidth at any given time and location, which necessitates expensive recording equipment and labour cost at various locations. A number of countries, including the USA, are opening up TV and radar bands for sharing with other applications. Google has taken the lead by opening its spectrum database for TV whitespaces. Our solution goes beyond the state-of-the-art Google spectrum database by providing the world’s first real-time radio spectrum database.

Radio Spectrum Database at UTS
The UTS’s Global Big Data Technologies Centre team has developed advanced sensing capability to deliver a low-cost, yet more robust radio spectrum database. By leveraging big data science, edge computing power, crowdsourcing, and low-cost SDR (software defined radio) adaptors, a real-time snapshot of the wireless spectrum can be recorded on any Android device. The spectrum data is aggregated and visualize onto a web dashboard, allowing industry stakeholders and regulators to better facilitate dynamic radio spectrum monitoring and sharing.

Highlights:

• World’s first real-time spectrum database
• Fast deployment and can cover a wide range of frequency
• Provide spectrum on-demand to IoT, industry 4.0 applications
• Rich datasets from millions of mobile users across various locations
• 24/7 cost-effective and real-time radio spectrum monitoring system
• Economical: $20 RTL-SDR adaptors and labor-free versus costly sensing equipment
• Scalable: Cloud deployment allows infrastructure to be scaled as user base grows (millions of users)
• Easy to use and install via Android Play Store
• User-friendly interface with Google Map embedded system

In the past we've seen somewhat similar projects with Electrosense, and the 'BigWhoop' project.