Academic literature on the topic 'Software radio'

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2007.<br>The use of older and slower protocols has become increasingly difficult to justify due to the rapid pace at which telecommunications are advancing. To keep up to date with the latest technologies, the communications system must be designed to accommodate the transparent insertion of new communications standards in all the stages of a system. The system should, however, also remain compatible with the older standards so as not to demand an upgrade of the older systems. The concept of a software defined radio was introduced to overcome these problems. In a software defined radio system, the functionality of the communications system is defined in software, which removes the the need for alterations to the hardware during technology upgrade. To maintain interoperatibilty, the system must be based on a standardised architecture. This would further allow for enhanced scalability and provide a plug-andplay feature for the components of the system. In this thesis, generic signal processing software components are developed to illustrate the creation of a basic software modem that can be parameterised to comply fully, or partially, to various standards.

Thesis (M.S.)--University of Missouri--Rolla, 2007.<br>Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed December 7, 2007) Includes bibliographical references (p. 171-173).

International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California<br>This paper provides an overview of software radio and its current state in the industry. Software radio is a technology in which all of the waveform processing, including the physical layer, of a wireless device moves into software. If designed properly, this approach leads to dramatically improved device flexibility, software portability, and reduced development costs. Of course, such a technology brings with it numerous challenges, from hardware components to power constraints to the regulatory environment.

Mestrado em Engenharia Electrónica e Telecomunicações<br>Esta dissertação teve como objectivo o desenvolvimento de parte de um receptor para Digital Audio Broadcasting (DAB) recorrendo aos conceitos ditados por Software Defined Radio (SDR). O receptor de rádio inclui a conversão de digital para analógico e a subsequente desmodelação de banda- base,pelo que é possível aceder à bit stream em qualquer ponto do sistema. A dissertação foi dividida em duas fases. Na primeira, o receptor completo foi simulado em MATLAB. Na segunda, o mesmo sistema foi implementado e testado numa placa XtremeDSP Development Kit-IV, a qual contêm um Field-Programmable Gate Array (FPGA). O sistema simulado foi testado com dois tipos de amostras. As primeiras consistiram em sinais DAB gerados em MATLAB e posteriormente distorcidos por diferentes canais também simulados pelo mesmo software. Foi assim possível fazer um estudo da probabilidade de erro quando o sinal é exposto a diferentes perturbações, como ruído, desvios na frequência e no tempo. O sistema foi ainda testado com amostras DAB reais. As constelações desmodelados mostraram o correcto funcionamento do sistema. Apenas parte do receptor simulado foi implementado no FPGA. A parte já desenvolvida consiste nas funções de desmodelação: desmodelação OFDM, desmodelação diferencial, frequency deinterleaving e demapeamento QPSK. O sistema de sincronização DAB não foi implementado. O sistema já desenvolvido é assim capaz de desmodelar um sinal DAB gerado no MATLAB, desde que este não contenha qualquer distorção. ABSTRACT: The aim of this dissertation was the development of part of a Digital Audio Broadcasting (DAB) receiver by means of Software Defined Radio (SDR). This radio receiver includes the Intermediate Frequency (IF) to baseband conversion and the subsequent baseband demodulation, thus one may access the bit stream in any point of the system. This dissertation was divided in two phases. In the first one, the whole DAB system was simulated in MATLAB. In the second, the receiver was implemented and tested in an XtremeDSP Development Kit-IV platform, which includes a Field-Programmable Gate Array (FPGA). The simulated system was tested with two kinds of samples. The first ones were generated in MATLAB and subsequently distorted by different channel conditions also simulated in the same software. This well known DAB digital signal allowed us to perform a Bit Error Rate (BER) study with several channel conditions, such as noise, multipath, frequency and time offsets. Further on, real DAB samples were used for testing. The demodulated QPSK constellations showed the correct operation of the system. Only part of the simulated receiver was implemented in the FPGA. This part consists in the channel demodulation functions: OFDM demodulation, differential demodulation, frequency deinterleaving and QPSK demapper. The DAB synchronization block was not implemented. The developed system is able to recover the modulated bit stream from the digital signal produced in MATLAB, since this signal is free of noise, frequency and time offsets