This thesis investigates the design and implementation of turbo codes over the GNU radio. The turbo codes is a class of iterative channel codes which demonstrates strong capability for error correction. A software defined radio (SDR) is a communication system which can implement different modulation schemes and tune to any frequency band by means of software that can control the programmable hardware. SDR utilizes the general purpose computer to perform certain signal processing techniques. We implement a turbo coding system using the Universal Software Radio Peripheral (USRP), a widely used SDR platform from Ettus. Detail configuration and performance comparison are also provided in this research.

The thesis focuses on issues around communication system with the Direct Spread Spectrum Signal Signal. This work outlines the theoretical analysis of this technique and subsequently is created a communication system concept. The device concept is adjusted so that the device can be used as a laboratory device, presenting the spreading technique. This thesis offers a comprehensive and detailed description of the communication system construction, including design of transmitter, receiver and a common transmission channel. In conclusion are stated the results of devised communication system.