Software-Defined Radio: Build Your Own SDR with RF Bricks

Software-defined radio is often presented as a software problem. In practice, the RF hardware still matters. Build Your Own Software-Defined Radio by Thomas Duden takes a different route, focusing on how real signal paths are built, measured, and refined using modular RF hardware combined with PC and FPGA-based processing.

Rather than starting from abstract theory, the book follows the structure of an actual SDR system, from the antenna to the demodulator and beyond. Each stage is broken down into manageable hardware “RF Bricks” that can be combined, tested, and modified as needed.

From Mechanics to Software-Defined Radio RF Bricks

The first chapters deal with the physical side of an SDR setup. The RF Brick template, chassis, and 19-inch module carrier establish a mechanical framework that supports experimentation without turning into a one-off prototype. This structure is used consistently throughout the book.

Within this structure, individual RF Bricks are introduced: antennas, band filters, preamplifiers, PLLs, and demodulators. Each brick is explained on its own, with attention to construction, adjustment, and measurement. The emphasis stays on what can actually be built, connected, and tested on the bench.
 

Assembling Complete Software-Defined Radio Signal Chains

Rather than stopping at individual modules, the book shows how RF Bricks are assembled into complete software-defined radio signal chains. Practical examples include direct conversion receivers, multiband configurations, and narrowband architectures, with a detailed walk through of an example filter, from calculation and construction to tuning.

Measurement plays a central role throughout the book. Tools such as the NanoVNA are used to verify filter behavior, impedance matching, and noise performance. Dedicated RF measurement Bricks, including signal generators, noise sources, notch filters, and impedance bridges, are treated as part of the same modular system rather than separate lab equipment.

Software and FPGA Integration

On the software side, the book covers PC-based SDR tools such as SoapySDR, GQRX, CubicSDR, and SDR++, focusing on configuration, bandwidth handling, and practical tweaks. GNU Radio is introduced step by step, from basic GUI elements to SSB demodulation and optimized message handling.

For readers interested in hardware acceleration, later chapters move into FPGA-based SDR. VHDL building blocks, ADC and DAC integration, oversampling, and complete SSB and CW signal chains are developed with the same hands-on mindset used throughout the book.

A Practical Reference for Software-Defined Radio Experimenters

It will appeal to engineers and radio amateurs who enjoy working at the bench and want a hands-on reference they can return to while building and experimenting.