Calculation of aggregate interference power from ultra wideband devices

Low power ultra-wideband (UWB) technology offers new and promising possibilities for high data rate communications and high resolution sensors. The key issue for the deployment of such systems is the coexistence of UWB systems with narrowband systems located in the same frequency range. Therefore, the maximum transmit power spectral density (PSD) has to be regulated in such a way that no harmful interference occurs. For the assessment of the interference from multiple UWB devices, theoretical models for the aggregate interference PSD at the victim receiver are used. The paper introduces an interference model that allows accurate calculation of the interference and is convenient to use. The results show the sensitivity of the aggregate interference on wave propagation effects. According to the realistic models, the aggregate interference power of UWB devices is most unlikely to exceed the protection criteria for a point-to-point communication link at 4 GHz.