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Diode string was used as the effective on-chip electrostatic discharge (ESD) protection device. To reduce the leakage current and the layout area, an area-efficient and low-leakage diode string is proposed in this paper. The standard steps of P− implantation and silicide blocking in CMOS process are used in this design to realize the proposed diode string with stacked P−/N+ diodes. The test devices of the proposed design have successfully been verified in the silicon chip. With the high ESD robustness, low leakage current, and small layout area, the proposed diode string can be a better solution for on-chip ESD protection applications. [ABSTRACT FROM AUTHOR]

This paper proposes an effective real-time video uplink (UL) framework for mobile wireless camera networks (WCN) over an orthogonal frequency-division multiple access (OFDMA), based infrastructure. Mobile wireless camera stations (CSs) transmit their videos in real time to a base station (BS) so that these live video streams can be archived or fed to subscribers to facilitate real-time video monitoring. Based on the utility function driven by video quality, the target bit rate resulting in the highest possible utility is quickly set for each UL video. To optimize system performance, a real-time video packet scheduler and a spectral-efficient resource-allocation policy are derived. This scheduler is also capable of exploiting the inherent diversity gain due to channel variations. Using fourth-generation (4G) mobile network protocols and a realistic wireless channel model, it is demonstrated through our extensive simulations that our proposed method can significantly enhance utility, boost spectral efficiency, and stabilize video quality. [ABSTRACT FROM PUBLISHER]

Table-lookup-and-addition methods provide multiplierless function evaluation using multiple lookup tables and a multioperand adder. In spite of their high-speed operation, they are only practical in low-precision applications due to the fast increase in table size with precision width. In this brief, we present two methods for table size reduction by decomposing the original table of initial values into two or three tables with fewer entries and/or smaller bit width. The proposed table decompositions do not incur any extra rounding errors so that the original table can be completely recovered. Experimental results demonstrate significant saving of table sizes compared with the best of the prior designs of the multipartite methods. [ABSTRACT FROM AUTHOR]

A WiMAX radio resource allocation (WRA) problem is investigated in the context of IPTV broadcasting over mobile WiMAX multicast, broadcast services (MBS) channels. The goal is to maximize quality of services, in terms of number of subscribers served, number of IPTV channels carried, and perceived video qualities of individual viewers, subject to constraints on multicast channel capacities and space-time channel quality variations. We present an efficient heuristic algorithm based on the Pareto principle that achieves near-optimal results in polynomial time complexity. Extensive simulations are conducted to compare this new approach against state-of-the-art heuristic algorithms and consistent superior performance has been observed. [ABSTRACT FROM PUBLISHER]

We propose Opportunistic Layered Multicasting (OLM), a joint user scheduling and resource allocation algorithm that provides enhanced quality and efficiency for layered video multicast over Mobile WiMAX. This work is a lead off and complete synergy of layered video multicasting with opportunistic concept. The target application is characterized by groups of users acquiring popular video programs over a fading channel. To accommodate various bandwidth requirements and device capability, video streams are coded into base and enhancement layers using scalable video coding technology. Correspondingly, the optimization problems, which select the best subset of users to receive a specific video layer and assign the most appropriate modulation and coding scheme for this video layer, are specifically formulated for both video layer types. We also design fast and effective algorithms to bridge the gap between theoretical throughput capacity and implementation concerns. Thus, the basic video quality can be efficiently guaranteed to all subscribers while creating most utility out of limited resources on enhancement information. To overcome the inevitable packet loss in a multicast session, an FEC rate adaptation scheme to approach theoretical performance is also presented. Favorable performance of the proposed algorithms is demonstrated by simulations utilizing realistic Mobile WiMAX parameters. [ABSTRACT FROM PUBLISHER]