Ultra wideband sensors are well suited to detect or image hidden objects. In order to approach the physical limits of ultra wideband detection and imaging, super resolution techniques have to be applied for processing the captured sensor data. These techniques are very sensitive to the quality of the measurement data, i. e. their bandwidth, their dynamic range and their time stability. Implementation issues of the sensor electronics implied by those parameters are considered and corresponding demands are deduced. In this article a sensor conception is presented which largely meets these requirements. It is based on a digital wideband correlator which promotes monolithic integration of the system components in a low cost RF-technology and provides superior jitter performance. Its working principle will be considered as well as the implementation of some fundamental circuits.