DeepSea Developments Modularizes the RTL-SDR for Multi-Receiver Software-Defined Radio Projects

California-based Internet of Things (IoT) design house DeepSea Developments is looking to make it easier to bring multiple RTL-SDR software-defined radio dongles to bear on a given problem — with open source motherboards designed to house up to four Realtek RTL2832U-based modules.

"DeepRad is a modular version of the RTL-SDR, a product beloved by radio enthusiasts," explains DeepSea Developments co-founder and chief executive officer Nick Velasquez of his company's creation. "However, DeepRad offers distinct advantages. Its modularity makes integration far simpler, side-stepping the complexities of designing an RTL-SDR from scratch (such as RF considerations and chip stocking issues). DeepRad is a versatile option for integrating many different radio functions into whatever projects you’re working on today."

The RTL-SDR family of USB software-defined radio dongles started life as an observation by Eric Fry that cheap digital TV dongles built around the Realteak RTL2832U controller could be used as generic receive-only SDRs. This progressed into the design of specific RTL-SDR dongles — and now DeepSea is looking to offer something a little more modular with DeepRad.

The DeepRad dongles themselves are simply a modularized version of an RTL-SDR, with a Realtek RTL2832U controller and an R860T tuner. Unlike a standard RTL-SDR dongle, though, there's no USB connection: instead, the modules are designed for installation into a carrier "motherboard" that includes USB connectivity — with one- and four-module carriers already designed and the suggestion the concept could scale up to 20 modules.

This, DeepSea argues, allows the RTL-SDR concept to scale to multi-receiver custom projects more easily. "You could build a board with several DeepRads and a Raspberry Pi to notify you of an activity in a specific frequency," Velasquez suggests. "You could build an inefficient version of your regular radio to listen to your favorite station, connect it to the cloud with an SBC [Single Board Computer], and run an AI [Artificial Intelligence] algorithm to analyze the broadcast content. Integrate DeepRad into a board with a motor control to follow the trajectories of passing satellites, such as NOAA's weather satellites or the International Space Station."

While DeepSea has promised that the design of its one- and four-module carrier boards will be released under an unspecified open source license, to act as a basis for those looking to build custom boards that integrated one or more DeepRad modules, the company had not yet done so at the time of writing.

More information on the project is available on the DeepRad Crowd Supply page, with a crowdfunding campaign to produce the modules and carriers due to launch soon.