DB-SDR – Prototyping of Software-Defined Radio Applications
Since radio communication methods are getting more and more complex (like WLAN, UMTS, LTE etc.), the throughput steadily increases. This enables mobile devices like mobile phones or laptops to use broadband applications such as High Definition Television (HDTV), video conferences or 3D online games.
Today‘s mobile devices have to process many different communication standards to ensure, that they can operate worldwide. Up to now, these methods are mapped to heterogeneous hardware platforms with dedicated hardware modules.
During operations, mobile devices only use few communication standards simultaneously. Therefor, flexible software-based approaches are used in modern systems, which are based on high- performant, universal and reconfigurable processors. These approaches, called „Software-Defined Radio (SDR)“, allow for the exchange of applications at runtime. In addition, they ensure fast and cheap developments of new communication standards, since these standards can be described by high level programming languages, like C/C++.
The Extension Module DB-SDR
The Cognitronics and Sensor Systems Group (K&S) developed the extension module DB-SDR for the Rapid-Prototyping-System RAPTOR to provide a prototyping-platform for baseband-algorithms. This module contains two 12 Bit AD-converter, which transform received analog signals into digital values at 64 MSamples/sec. These converters support signal widths up to 32 MHz. Transmissions are proceeded by two 14 Bit DA-converters, which ensure a Nyquist frequency of 64 MHz.
The DB-SDR is compatible to the USRP-System (Universal Software Radio Peripheral), which is distributed by Ettus Research. The compatibility ensures, that a multitude of RF-frontend modules can be used to cover frequency ranges from 0 to 5 GHz.
Prototyping of SDR-Applications
The K&S Group explores, how several SDR- applications can be mapped to different hardware architectures. One of these architectures is the CoreVA-VLIW-Processor, which has been developed in this group, too.
In combination with the RAPTOR-System, the DB- SDR represents a flexible platform for the exploration and optimization of baseband-algorithms.
The GNU Radio Project provides a comfortable development environment for the implementation of communication algorithms on Windows or Linux PCs. Therefore, an interface has to be implemented, which connects GNU Radio to the DB-SDR.
Dipl.-Ing. Boris Hübener
Fon.: +49 521 106-12041