A low-cost desktop software defined radio design environment using MATLAB, simulink, and the RTL-SDR

TLDR

In recent years, powerful DSP software and affordable SDR devices such as the RTL‑SDR have made software‑defined radio accessible to engineers, students, and hobbyists, enabling wide‑band RF spectrum scanning from 25 MHz to 1.75 GHz. The article aims to describe the RTL‑SDR’s capabilities and develop a hands‑on, open‑courseware for SDR. The authors created open‑courseware and lab materials that illustrate RTL‑SDR operation for teaching DSP and communications. These materials have been adopted in senior undergraduate courses and are freely available, enhancing DSP and communications instruction.

Abstract

In the last five years, the availability of powerful DSP and communications design software, and the emergence of relatively affordable devices that receive and digitize RF signals, has brought SDR to the desktops of many communications engineers. However, the more recent availability of very low cost SDR devices such as the RTL-SDR, costing less than $20, has brought SDR to the home desktops of undergraduate and graduate students, as well as professional engineers and the maker communities. Since the release of the various open source drivers for the RTL-SDR, many in the digital communications community have used this device to scan the RF spectrum and digitize I/Q signals that are being transmitted in the range 25 MHz to 1.75 GHz. This wide operating range enables the sampling of frequency bands containing signals such as FM radio, ISM signals, GSM, 3G and LTE mobile radio, GPS, and so on. In this article we will describe the opportunity and operation of the RTL-SDR, and the development of a handson, open-courseware for SDR. These educational materials can be integrated into core curriculum undergraduate and graduate courses, and will greatly enhance the teaching of DSP and communications theory, principles, and applications. The lab and teaching materials have recently been used in senior (fourth year undergraduate) courses and are available as open course materials for all to access, use, and evolve.