The future of sensor interface electronics

Abstract

In the context of progress towards intelligent sensin systems, future technologies of sensor interface electronics are described. Functions of interface electronics are expanding in several directions and will contain new computing paradigms. One direction is the expansion to multidimensional sensing systems. One-dimensional signal processing is extending towards two-dimensional signal processing. Image processing is a typical example of two-dimensional signal processing. In the near future, sensed image processing will be carried out by electronics integrated with image-sensing devices in place of separate computers. Moving-image processing is done by parallel processing. Then we can get almost real-time results for feature extraction of the object or signal compression for communication. Moving-image compression is playing a key role in the present multimedia area. Another direction is the expansion towards multilayer signal processing. Advanced sensing systems have a hierarchical structure. Sensed signal processing is done in the lower layer, which entails a direct interface to the sensor device. More abstract information processing is carried out in the upper layer, where the processing is based on knowledge of the object and sensors. We can call it knowledge processing, and cite examples, such as target recognition and reasoning of the object state. Special information processing is carried out in the middle layer. The missions of the middle-layer processing are feature extraction from the sensor signal and multisensory signal integration and fusion. An important role of the future sensor interface electronics is multimodal sensor processing. In particular, fusion of the signals from various kinds of sensing devices will give us a higher order of information which we can never get without multimodal sensor signal processing. From the viewpoint of function, the future image of sensor interface electronics can be described as a major enlargement of present functions. However, the physical size of the future hardware will be much more compact and it will be integrated or embedded in the sensing devices.