In this paper, we propose a low-complexity frequency offset insensitive detection method for the 2.45 GHz LR-WPAN demodulator. In IEEE 802.15.4 LR-WPAN (Low-Rate Wireless Personal Area Network) specification, the frequency offset as highest 80 ppm in the 2.45 GHz band is recommended for low-complexity, low-cost, and low-power implementation. The proposed detection method is verified such that the performance is within 2 dB of the optimal coherent detection with low complexity, which is less than half in comparison with conventional detection methods.

Route optimization for network mobility is a key technique for providing a node in a mobile network (Mobile Network Node or MNN) with high quality broadband communications. Many schemes adding route optimization function to Network Mobility (NEMO) Basic Support protocol, the standardized network mobility management protocol from the IETF nemo working group, have already been proposed in recent years. One such scheme, a scheme using Hierarchical Mobile IPv6 (HMIPv6) aims to overcome micromobility management issues as well by applying a mechanism based on HMIPv6. The traditional scheme, however, suffers from a significant number of signaling messages as the number of MNNs and/or the number of their Correspondent Nodes (CNs) increase, because many messages notifying the MNNs' Home Agents (HAMNNs) and the CNs of the mobile network's movement are generated simultaneously each time the mobile network moves to the domain of another micromobility management router (Mobility Anchor Point or MAP). This paper proposes a scheme to overcome this problem. Our scheme reduces the number of signaling messages generated at the same time by managing the mobility of MNNs using multiple MAPs distributed within a network for load sharing. The results of simulation experiments show that our scheme works efficiently compared to the traditional scheme when a mobile network has many MNNs and/or these MNNs communicate with many CNs.

A fuzzy logic control battery equalizing controller (FLC-BEC) is adopted to control the cell voltage balancing process for a series connected Li-ion battery string. The proposed individual cell equalizer (ICE) is based on the bidirectional Cuk converter operated in the discontinuous capacitor voltage mode (DCVM) to reduce the switching loss and improve equalization efficiency. The ICE with the proposed FLC-BEC can reduce the equalizing time, maintain safe operations during the charge/discharge state and increase the battery string capacity.

An enormous amount of multimedia data will be transmitted by various devices connected to the wireless personal area network, and this network environment will require very high transmission capacity. In this letter, we apply multiple antennas to the MB-OFDM UWB system for high performance. With an emphasis on a preamble design for multi-channel separation, we address the channel estimation in the MB-OFDM system with multiple antennas. By properly designing each preamble so that the multiple antennas remain orthogonal in the time domain, the channel estimation can be applied to the MB-OFDM specification in the case of more than 2 transmit antennas. By using the multiple-antenna scheme and proposed channel estimation technique, the reliability and performance of the MB-OFDM system can be improved.

A new adaptive model based on fuzzy integrals has been presented and used for combining three well-known methods, Eigenface, Fisherface and SOMface, for face classification. After training the competence estimation functions, the adaptive mechanism enables our system the filtering of unsure judgments of classifiers for a specific input. Comparison with classical and non-adaptive approaches proves the superiority of this model. Also we examined how these features contribute to the combined result and whether they can together establish a more robust feature.

A fast algorithm to speed up the search process of vector quantization encoding is presented. Using the sum and the partial norms of a vector, some eliminating inequalities are constructeded. First the inequality based on the sum is used for determining the bounds of searching candidate codeword. Then, using an inequality based on subvector norm and another inequality combining the partial distance with subvector norm, more unnecessary codewords are eliminated without the full distance calculation. The proposed algorithm can reject a lot of codewords, while introducing no extra distortion compared to the conventional full search algorithm. Experimental results show that the proposed algorithm outperforms the existing state-of-the-art search algorithms in reducing the computational complexity and the number of distortion calculation.

The intra-prediction unit is an essential part of H.264 codec, since it reduces the amount of data to be encoded by predicting pixel values (luminance and chrominance) from their neighboring blocks. A dedicated hardware implementation for the intra-prediction unit is required for real-time encoding and decoding of high resolution video data. To develop a cost-effective intra-prediction unit this paper proposes a novel architecture of intra-predictor generator, the core part of intra-prediction unit. The proposed intra-predictor generator enables the intra-prediction unit to achieve significant clock cycle reduction with approximately the same gate count, as compared to Huang's work [3].

In this paper, efficient symbol timing synchronization algorithms for IEEE 802.11a/g wireless LAN systems in multipath channels are proposed. For improved accuracy, the algorithms utilize an effectively elongated training symbol together with nonlinear soft-limiting of the correlator output. The algorithms allow efficient utilization of the guard interval in multipath channels. Simulation results show that the proposed algorithms significantly outperform conventional algorithms.

This investigation applies the adaptive fuzzy-neural observer (AFNO) to synchronize a class of unknown chaotic systems via scalar transmitting signal only. The proposed method can be used in synchronization if nonlinear chaotic systems can be transformed into the canonical form of Lur'e system type by the differential geometric method. In this approach, the adaptive fuzzy-neural network (FNN) in AFNO is adopted on line to model the nonlinear term in the transmitter. Additionally, the master's unknown states can be reconstructed from one transmitted state using observer design in the slave end. Synchronization is achieved when all states are observed. The utilized scheme can adaptively estimate the transmitter states on line, even if the transmitter is changed into another chaos system. On the other hand, the robustness of AFNO can be guaranteed with respect to the modeling error, and external bounded disturbance. Simulation results confirm that the AFNO design is valid for the application of chaos synchronization.

The present paper introduces the construction of a class of sequence sets with zero-correlation zones called zero-correlation zone sequence sets. The proposed zero-correlation zone sequence set can be generated from an arbitrary perfect sequence and an arbitrary Golay complementary sequence pair. The proposed construction is a generalization of the zero-correlation zone sequence construction previously reported by the present author. The proposed sequence set can successfully provide CDMA communication without co-channel interference.

Configurable clock is necessary for many applications such as digital communication systems, however, using the conventional direct digital frequency synthesizer (DDS) as a pulse or clock generator may cause jitter problems. People usually employ phase-interpolation approaches to generate a pulse or clock with correct time intervals. This work proposes a new phase-interpolation DDS scheme, which uses the output of the phase accumulator to provide an initial voltage on an integration capacitor by pre-charging in the first phase, and then performs integration operation on the same integration capacitor in the second phase. By using single capacitor integration, the instability of the delay generator existed in the phase-interpolation DDS can be avoided, and the impact caused by capacitance error in the circuit implementation also can be reduced. Furthermore, without ROM tables, the proposed DDS using pre-charging integration not only reduces the spurious level of the clock output, but also has a low hardware complexity.

The RFID (Radio Frequency IDentification) tag technology is expected as a tool of localization. By the localization of RFID tags, a mobile robot which installs in RFID readers can recognize surrounding environments. In addition, RFID tags can be applied to a navigation system for walkers. In this paper, we propose an adaptive likelihood distribution scheme for the localization of RFID tags. This method adjusts the likelihood distribution depending on the signal intensity from RFID tags. We carry out the performance evaluation of estimated position error by both computer simulations and implemental experiments. We show that the proposed system is more effective than the conventional system.

In this letter, we address a carrier frequency offset (CFO) estimator with a large estimation range for ultra-wideband multi-band orthogonal frequency division multiplexing (UWB MB-OFDM) systems. We find by simulations that the proposed CFO estimator yields an improved estimation range, maintaining the same estimation performance and complexity in comparison with the conventional estimator.

We formulated the excitation rate of VUV and emitted visible light from rare gas on PDP by using the Boltzmann equation with electron-atom collision integral term and obtained the excitation rate as the function of Temperature and Mass. This form of excitation rate was firstly derived in PDP area. In addition we showed the Pressure dependence of intensity ratio of Ne/VUV as the application of our excitation rate formulae.

This paper presents a fuzzy partitioning method that adaptively divides a global key pool into multiple partitions by a fuzzy logic in the statistical filtering-based sensor networks. Compared to the original statistical filtering scheme, the proposed method is more resilient against node compromise.

All-optical wavelength conversion and modulation format conversion will be needed in the next generation high-speed optical communication networks. We have proposed and successfully demonstrated the error free operation of all-optical modulation format conversion from NRZ-OOK to RZ-BPSK using SOA based MZI wavelength converter. In this paper, we experimentally investigate the wavelength conversion characteristics of the proposed NRZ-OOK/RZ-BPSK modulation format converter. The results show that error free modulation format conversion is possible over the entire C band.

A multiple-antenna receiving and combining scheme is proposed for high-data-rate transmitted-reference (TR) Ultra-Wideband (UWB) systems. The nonlinearity of the inter-symbol interference (ISI) model is alleviated via simple antenna combining. Under the simplified ISI model, frequency domain equalization (FDE) is adopted and greatly reduces the complexity of the equalizer. A simple estimation algorithm for the simplified ISI model is presented. Simulation results demonstrate that compared to the single receive antenna scheme, the proposed method can obtain a significant diversity gain and eliminate the BER floor effect. Moreover, compared to the complex second-order time domain equalizer, FDE showed better performance robustness in the case of imperfect model estimation.

This paper addresses the problem of view invariant action recognition using 2D trajectories of landmark points on human body. It is a challenging task since for a specific action category, the 2D observations of different instances might be extremely different due to varying viewpoint and changes in speed. By assuming that the execution of an action can be approximated by dynamic linear combination of a set of basis shapes, a novel view invariant human action recognition method is proposed based on non-rigid matrix factorization and Hidden Markov Models (HMMs). We show that the low dimensional weight coefficients of basis shapes by measurement matrix non-rigid factorization contain the key information for action recognition regardless of the viewpoint changing. Based on the extracted discriminative features, the HMMs is used for temporal dynamic modeling and robust action classification. The proposed method is tested using real life sequences and promising performance is achieved.

The ability to mentalize is essential for human socialization. Such ability is strongly related to communication. In this paper, I discuss the development of mentalizing and communication from the perspectives of a new idea, Developmental Cybernetics, and developmental cognitive neuroscience. Children only attributed intention to a robot when they saw it behaving as a human and displaying social signals such as eye gaze. The emergence of powerful new methods and tools, such as neuroimaging, now allows questions about mentalizing to resolved more directly than before.

In this paper, a channel allocation scheme is studied for overlay wireless networks to optimize connection-level QoS. The contributions of our work are threefold. First, a channel allocation strategy using both horizontal channel borrowing and vertical traffic overflowing (HCB-VTO) is presented and analyzed. When all the channels in a given macro-cell are used, high-mobility real-time handoff requests can borrow channels from adjacent homogeneous cells. In case that the borrowing requests fail, handoff requests may also be overflowed to heterogeneous cells, if possible. Second, high-mobility real-time service is prioritized by allowing it to pre-empt channels currently used by other services. And third, to meet the high QoS requirements of some services and increase the utilization of radio resources, certain services can be transformed between real-time services and non-real-time services as necessary. Simulation results demonstrate that the proposed schemes can improve system performance.