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Position sensitive detectors (PSDs), used in high-end biotechnology, are based on optical sensors built over quadrant photodetectors (QPDs) or active pixel sensor (APS). These devices are intended to measure slight movements of laser spots. The QPD are, by far, the best approach in terms of resolution and noise, but requires complex and expensive x - y micropositioners to perform sensor alignment with the incoming laser spot. The APSs are more versatile devices that can virtually align with the spot by means of device configuration. However, due to its intrisic digital nature, the SNR and the resolutions are degraded in APS. In this paper, a new type of device called configurable QPD and its theory of operation is presented. This new device combines the analog operation of the QPD with the configurability of the APS, by means of combining photodetectors elements with analog switches in a matrix-shaped architecture. Finally, a prototype chip has been fabricated and tested and its measurements results are presented.

The maximum data rate in today's available multidrop backplanes is significantly limited due to signal integrity concerns. In this brief, a novel gigabit multidrop serial link configuration for high-speed digital systems based on newly developed asymmetrical broadband power splitters with matching trace impedance, is presented. The proposed power splitter features good impedance match at all ports without the insertion losses being inherent to common resistive power splitters. Experimental results obtained from implemented prototypes demonstrate a satisfactory operation of the proposed multidrop serial backplane for a data rate above 3.5 Gbps.

In recent years, IEEE 802.15.4-based Wireless Sensor Networks (WSN) have experienced significant growth, mainly motivated by the standard features, such as small size oriented devices, low power consumption nodes, wireless communication links, and sensing and data processing capabilities. In this paper, the development, implementation and deployment of a novel fully compatible IEEE 802.15.4-based WSN architecture for applications operating over extended geographic regions with high node mobility support, is described. In addition, a practical system implementation of the proposed WSN architecture is presented and described for experimental validation and characterization purposes.

Scheduling algorithms developed for virtual-output-queuing (VOQ) switches have focused on the throughput enhancement, rather than provide QoS guarantees for different priority levels. Presented, is a new scheduling scheme to effectively support real-time and data applications in VOQ switches with negligible complexity increment.