Techniques for optimal DSSS code selection for SAW multi-sensor systems

Abstract

Direct Sequence Spread Spectrum (DSSS) codes have a variety of applications, including implementing code diversity in wireless surface acoustic wave (SAW) multi-sensor systems. Such systems generally suffer from code collision problems, necessitating complex post-processing to avoid negatively impacting sensor calibration and system accuracy. Thus, development of groups of codes that exhibit very low cross-correlation is desirable to implement code diversity in passive wireless sensor systems. This paper discusses generation and analysis of Gold codes, a know class of codes with desirable cross-correlation properties. A logical criteria-based method for the `exhaustive' analysis of codes of a given length is also presented, applying a selected set of screening techniques to rapidly evaluate all possible candidate codes to a sufficient degree. Using this technique, sets of codes can be found that perform well in asynchronous correlation-based wireless sensor systems, reducing the need for complex post-processing.