DAB transmission on your PC : Différence entre versions

Version actuelle datée du 9 mars 2008 à 00:32

Introduction

This article shows that it is possible to generate and transmit a DAB, DAB+, or T-DMB signal using a recent PC running Linux and a software radio peripheral. This is not intended for pirate DAB but for testing, development, experimentation and also demonstration that DAB technology is not as complex as some like to say.

The function from the audio encoder, service multiplexer, ensemble multiplexer and COFDM modulator are performed in software on the CPU from the PC. The result is baseband complex samples from the DAB/DAB+/T-DMB signal that can then be played on a hardware radio peripheral (the equivalent of a soundcard but for radio frequencies) for transmission at desired radio frequency.

Equipment

For this experiment such a configuration was used:

Hardware

• PC: Pentium IV 2.4 GHz PC, 512MB memory, USB2 interface
• Universal Software Radio Peripheral (USRP) from Ettus (~700$)
  • Basic TX daughterboard (~75$)

Software

• Ubuntu Linux Feisty (or higher)
• CRC MMBtools CD: the software implementation of DAB/DAB+/T-DMB from CRC Research Center in Canada

CRC MMBTools

The software implementation is divided in 3 main tools

• The multiplexer
• The modulator
• The samples player