Guest Editorial: Evolutionary Advancements in Wireless Software Defined Radio Systems

Abstract

The field of wireless communications over the years has been constantly making significant advancements in the domain of Software Defined Radios (SDRs). These reconfigurable radios are also capable to learn from their environment like the spectrum and then undertake rapid decisions based on its selfdefined policies leading to the development of wider range of new applications. Thus, new topics and concepts are not only been investigated in the Digital Signal Processing domain but also in the Cognitive Radio domain for an effective and efficient use of the spectrum. Using such technologies with widely accepted international standards like the Software Communications Architecture (SCA) in military software defined radios also requires that they go through the testing and certification processes. Thus, in this Special Issue of the Springer Journal of Signal Processing Systems, all these topics leading towards the evolution of SDRs are discussed. This Special Issue comprises of three sets containing a total of nine articles. The first set of articles put focus on the various cognitive radio technologies like Dynamic Spectrum Access and Spectrum Sensing. The still existing inefficient use of the spectrum is discussed in various SDR research communities. New and innovative ideas are continuously investigated to use the spectrum in the most efficient way in order to meet the ever growing demands of high data throughput. Use of Cognitive Radios is one such way to achieve it. These radios are able to sense the radio environment in order to identify portions of the spectrum that are unused at a specific time or location and are able to reconfigure themselves. Various algorithms and techniques are being investigated to achieve such results in a dynamic environment. The second set of articles discusses several advanced Digital Signal Processing techniques. All these techniques aim at optimizing operationally relevant criteria. These criteria vary from achieving higher robustness, lower bit error rates, longer communication ranges, and minimal energy consumption to faster deployments. The proofs of the achievements are given either by simulation or by prototype implementation on off-the-shelf low cost hardware. The third set of articles illustrates the importance test and certification of Software Defined Radios in the military domain using internationally accepted standard like the SCA. Standards like the SCA allow waveforms to be ported easily across heterogeneous platforms. It also provides neatly defined interfaces and Application Program Interfaces (APIs) aimed to increase portability and interoperability of radios. In the final phase of the development of SDRs, efficient ways of testing and agencies providing the certification of standards play a significant role. * Marc Adrat marc.adrat@fkie.fraunhofer.de