Phase-based methods for estimating the frequency of a sinusoid have typically suffered from a threshold effect, where for signal to noise ratio (SNR) below the threshold, the mean squared error of the estimate rapidly increases. Furthermore, it is a significant problem that the threshold is considerably high and strongly depends on frequency. To overcome the difficulties, a Kalman-based sinusoidal estimator bank (KSEB) is proposed. In the derivation of the KSEB, a four-channel filter bank and decimation technique are effectively used. The computer simulation also demonstrates the superiority of the KSEB to the other frequency estimators.

The single wire replacement attempts to replace a target wire by another wire without changing the circuit functionality. Due to the large searching space required, there is very little success in directly extending the single wire replacement technique to replace multiple wires at the same time. The objective in this paper is to propose a new logic transformation, called the alternative node (Alnode) technique, which attempts to replace multiple wires at a time. Basically, the transformation simultaneously replaces multiple input wires of a gate by a new set of input wires. To accomplish the transformation, we propose several speedup theorems for replacing multiple wires. In this paper, we also demonstrate that the Alnode technique can be applied to achieve power reduction for domino logic and wire length minimization in layouts. The experimental results are encouraging.

In this study, synchronization phenomena in chaotic oscillators coupled by a transmission line are investigated. In particular investigation using real circuits is done for the first time. It is confirmed that the chaotic subsystems synchronize, although signals propagating along the transmission line are affected by the time delay. Further the period-doubling bifurcation with varying the time delay and anti-phase synchronization phenomena are observed in our circuit model. Also the voltage distribution of transmission line is simulated in order to investigate whether the current flowing through the transmission line is constant or not. It is found that the subsystems synchronize although the current through the transmission line keeps on varying.

In this paper, we propose a frequency domain active noise control (ANC) system without a secondary path model. The proposed system is based on the frequency domain simultaneous perturbation (FDSP) method we have proposed. In this system, the coefficients of the adaptive filter are updated only by error signals. The conventional ANC system using the filtered-x algorithm becomes unstable due to the error between the secondary path, from secondary source to error sensor, and its model. In contrast, the proposed ANC system has the advantage not to use the model. In this paper, we show the principle of the proposed ANC system, and examine its efficiency through computer simulations.

This paper elucidates through experiments the improvement in the achievable bit error rate (BER) performance when space time transmit diversity (STTD) is applied to the wideband direct sequence code division multiple access (W-CDMA) forward link. First, laboratory experimental results clarify that the received path timing difference of transmitted signals from two antennas, due to the propagation delay, should be within a chip duration of approximately 1/4 and 1/2 with and without fast transmit power control (TPC), respectively, in order to achieve a prominent transmit diversity effect. We show that the required average received signal energy per bit-to-background noise spectrum density (Eb/N0) at the average BER of 10-3 using STTD is decreased by approximately 4.2 (1.7) dB compared to the case of single-antenna transmission at the maximum Doppler frequency, fD, of 5 Hz without (with) antenna diversity reception at a mobile station (MS) due to the increasing randomization effect of burst error. Furthermore, we elucidate that although the gain of STTD in field experiments is decreased compared to that in laboratory experiments, since the degradation in path search accuracy is greater due to the frequently changing delay time of each path in a real multipath-fading channel, the required average received signal energy per bit-to-interference plus background noise power spectrum density ratio (Eb/I0) at the average BER of 10-3 with STTD is decreased by approximately 1.3 to 1.5 (0.7 to 1.0) dB without (with) antenna diversity reception when fast TPC is not applied in the forward link. This indicates that STTD is effective for a channel without TPC such as a common control channel in a real multipath-fading channel.

This paper investigates the optimum transmit-antenna-weight generation method for adaptive antenna array transmit diversity (AAA-TD) in the W-CDMA forward link: AAA-TD with beam and null steering (BNST), AAA-TD with beam steering (BST), or switched beam transmit diversity with fixed weights (SBTD-FW). The achievable BER performance after carrier frequency calibration in the transmit beam pattern is compared among the three methods assuming a different carrier frequency in a 2-GHz band with the carrier separation of 184.5 MHz based on computer simulations. The simulation results show that the achievable BER performance in the forward link using AAA-TD with BNST is almost identical to that using AAA-TD with BST when there are many more interfering users than there are array antennas, except for the special case when a small number of higher rate users exists in the reverse link. This is because by performing carrier frequency calibration, the directions of the beam nulls are shifted from the real directions of arrival (DOAs) of the interfering users. However, we also show that the required transmit Eb/N0 at the average BER of 10-3 using AAA-TD with BST is decreased by approximately 1.0 to 1.2 dB compared to that using SBTD-FW with 12 beams.

We describe a method for object recognition with 2D image queries to be identified from among a set of 3D models. The pose is known from a previous step. The main target application is face recognition. The 3D models consist of both shape and color texture information, and the 2D queries are color camera images. The kernel of the method consists of a lookup table that associates 3D surface normals with expected image brightness, modulo albedo, for a given query. This lookup table is fast to compute, and is used to render images from the models for a sum of square difference error measure. Using a data set of 42 face models and 1764 (high quality) query images under 7 poses and 6 lighting conditions, we achieve average recognition accuracy of about 83%, with more than 90% in several pose/lighting conditions, using semi-automatically computed poses. The method is extremely fast compared to those that involve finding eigenvectors or solving constrained equation systems.

This paper describes the JAINTM JavaTM Call Control (JCC) Application Programming Interface (API), and its relationship to network protocols, in particular the Session Initiation Protocol (SIP). JCC is a high-level object-oriented open, standard API for Next Generation Network (NGN) softswitches that enables rapid creation, by third parties, of services that can run independently of the underlying network technology (e.g. wireless, wired, packet, IP, PSTN) and protocols. SIP is a protocol that has been proposed for a wide variety of uses in IP networks, including call control. We argue that instead of being competitors, JCC and SIP are complementary, with JCC offering higher-layer programming abstractions and protocol-independence, and demonstrate by examples how to map JCC version 1.0 to a SIP environment. We thus show that for common call control applications using JCC is simpler, faster and less maintenance intensive than using SIP directly.

It has been over a decade since the "Eigenfaces" approach to automatic face recognition, and other appearance-based methods, made an impression on the computer vision research community and helped spur interest in vision systems being used to support biometrics and human-computer interface. In this paper I give a personal view of the original motivation for the work, some of the strengths and limitation of the approach, and progress in the years since. Appearance-based approaches to recognition complement feature- or shape-based approaches, and a practical face recognition system should have elements of both. Eigenfaces is not a general approach to recognition, but rather one tool out of many to be applied and evaluated in the appropriate context.

The scatterometer is a real aperture radar capable to perform a set of normalized radar cross section measurements under different azimuth angles for each resolution cell. The main field of application of a wind scatterometer regards the sea surface wind field determination. As a matter of fact, once such measurements have been performed it is possible to determine the sea surface wind field by means of an inversion procedure. In this paper we present a novel inversion scheme which is an evolution of the procedure nowday used by the Italian Space Agency (ASI) under the Italian Processing and Archiving Facility (I-PAF). A full comparative study shows that the novel inversion scheme better behaves whenever light wind regimes are in question.

This paper evaluates the effect of inter-sector diversity with maximal ratio combining (MRC) coupled with coherent Rake combining and 2-branch antenna diversity reception in the transmit-power-controlled wideband direct sequence code division multiple access (W-CDMA) reverse link. We first elucidate based on laboratory experiments that the required average transmit signal energy per bit-to-background noise spectrum density ratio (Eb/N0) at the average bit error rate (BER) of 10-3 with inter-sector diversity using two sectors is decreased by approximately 1.4, 1.0, and 0.2 dB compared to that with inter-cell site diversity using two cell sites with antenna diversity reception due to the superiority of MRC to selection combining (SC), when the difference in the average path loss between a base station (BS) and a mobile station (MS) is Δ12 = 0, 3, and 6 dB, respectively. We also clarify in actual field experiments that the inter-sector diversity associated with Rake time diversity and antenna diversity further decreases the required average transmit power of a MS if the number of resolved paths is small such as 1 or 2 in each sector reception, even when the fading correlation between sectors is relatively large. Furthermore, we show that the required average transmit power of a MS for satisfying the average BER of 10-3 with inter-sector diversity is decreased above approximately 2.0-2.5 dB compared to that with one-sector reception, owing to the significantly increased inter-sector diversity effect in addition to the Rake time diversity and antenna diversity, when the fading correlation averaged over the measurement course is approximately 0.7.

A Fourier-optics based imaging system for electromagnetic interference (EMI) sources is presented. It is necessary to decrease undesired emissions in order to meet EMI requirements. To investigate this problem, a visualization of electromagnetic (EM) emitting fields is very useful. In this paper, we propose a passive imaging system of EM emitting fields based on Fourier optics. Amplitude and phase values of diffracted fields on an entrance pupil are acquired by using a six-port interferometer. The measured EM fields are then processed on a computer, and an image is retrieved using an inverse Fresnel transform. Experiments are presented, which demonstrate the potential of the proposed method. The proposed system is useful not only in the field of electromagnetic compatibility (EMC), but also for scientific elucidation to discuss the optics and microwave theory of the same viewpoint.

Techniques for human-motion recovery are applicable to a variety of areas, such as sports, dancing, virtual reality, and video-game production. The people who work in this area focus their attention on recovering information on the motion of individuals rather than groups of people. It is important to demonstrate the possibility of recovering descriptions of the 3-D motion in team sports, since such information is able to provide us with a variety of information on the relations among players. This paper presents a new experimental result on 3-D motion recovery from a team sport. The result was obtained by a non-rigid shape recovery technique based on images from uncalibrated cameras. The technique was applied to recovering the 3-D motion of the players in a mini-basketball game which was played in a gymnasium. Some attention is focused on the analysis of the players' motion. Satisfactory results were obtained.

In order to maintain the diversity of structures in the population and prevent premature convergence, I have developed a new genetic algorithm called DCGA. In the experiments on many standard benchmark problems, DCGA showed good performances, whereas with harder problems, in some cases, the phenomena were observed that the search was stagnated at a local optimum despite that the diversity of the population is maintained. In this paper, I propose methods for escaping such phenomena and improving the performance by reinitializing the population, that is, a method called each-structure-based reinitializing method with a deterministic structure diverging procedure as a method for producing new structures and an adaptive improvement probability bound as a search termination criterion. The results of experiments demonstrate that DCGA becomes robust in harder problems by employing these proposed methods.

In content-based image retrieval (CBIR), the content of an image can be expressed in terms of different features such as color, texture, shape, or text annotations. Retrieval methods based on these features can be varied depending on how the feature values are combined. Many of the existing approaches assume linear relationships between different features, and also require users to assign weights to features for themselves. Other nonlinear approaches have mostly concentrated on indexing technique. While the linearly combining approach establishes the basis of CBIR, the usefulness of such systems is limited due to the lack of the capability to represent high-level concepts using low-level features and human perception subjectivity. In this paper, we introduce a Neural Network-based Image Retrieval (NNIR) system, a human-computer interaction approach to CBIR using the Radial Basis Function (RBF) network. The proposed approach allows the user to select an initial query image and incrementally search target images via relevance feedback. The experimental results show that the proposed approach has the superior retrieval performance over the existing linearly combining approach, the rank-based method, and the BackPropagation-based method.

As a new category of the optical application system integrated with electronics, the opto-electronic information system (OEIS) is presented. Combination of the different characteristic technologies, optics and electronics, is expected to be useful for development of an effective and high-performance information systems. The properties of the optical technologies such as parallelism, high-speed, and large information capacity can be utilized for information processing. Even if some of the functions are emulated by the electronics, the optics give more effective solutions. To implement the OEIS, various optoelectronic devices and fabrication technologies are available including vertical cavity surface emitting lasers and spatial light modulators. There are two forms of system construction for the OEIS: an application of optics to an electronic-based system and the reversed form. As examples of the OEIS, the parallel matching architecture (PMA) and the thin observation module by bound optics (TOMBO) are presented. The PMA is an architecture of parallel computing system specified for global processing. This architecture shows a typical strategy to utilize the optical interconnection capability with flexibility of the electronic technology. The TOMBO presents possibility of morphological conversion using combination of the optical and electronic technologies. A compound-eye imaging system and post digital processing enable us to realize a very thin image capturing system. The issues related on development of the OEIS are proper usage of optics, effective fusion of the optical and electronic technologies, methodologies for system construction, fabrication supporting tools, and development of attractive demonstrators other than communication and interconnection fields.

The concept of stochastic association has originally been proposed in relation to single-electron devices having stochastic behavior due to quantum effects. Stochastic association is one of the promising concepts for future VLSI systems that exceed the conventional digital systems based on deterministic operation. This paper proposes a CMOS stochastic associative processor using PWM (pulse-width modulation) chaotic signals. The processor stochastically extracts one of the stored binary patterns depending on the order of similarity to the input. We confirms stochastic associative processing operation by experiments for digit pattern association using the CMOS test chip.

In order to assess the possible impacts of meteors with spacecraft, which is among major hazard in the space environment, it is essential to establish an accurate statistics of their mass and velocity. We developed a radar-optical combined system for detecting faint meteors consisting of a powerful VHF Doppler radar and an ICCD video camera. The Doppler pulse compression scheme is used to enhance the S/N ratio of the radar echoes with very large Doppler shifts, as well as to determine their range with a resolution of 200 m. A very high sensitivity of more than 14 magnitude and 9 magnitude for radar and optical sensors, respectively, has been obtained. Instantaneous direction of meteor body observed by the radar is determined with the interferometry technique. We examined the optimum way of the receiving antenna arrangements, and also of the signal processing. Its absolute accuracy was confirmed by the optical observations with background stars as a reference. By combining the impinging velocity of meteor bodies derived by the radar with the absolute visual magnitude determined by the video camera simultaneously, the mass of each meteor body was estimated. The developed observation system will be used to create a valuable data base of the mass and velocity information of faint meteors, on which very little is known so far. The data base is expected to play a vital role in our understanding of the space environment needed for designing large space structures.

This paper investigates the interference suppression effect from much higher rate dedicated physical channels (DPCHs) of a parallel-type coherent multistage interference canceller (COMSIC) with iterative channel estimation (ICE) by laboratory experiments in the transmit-power-controlled W-CDMA reverse link. The experimental results elucidate that when two interfering DPCHs exist with the spreading factor (SF) of 8 and with the ratio of the target signal energy per bit-to-interference power spectrum density ratio (Eb/I0) of fast transmit power control, ΔEb/I0, of -6 dB (which corresponds to 64 simultaneous DPCHs with SF = 64, i.e., the same symbol rate as the desired DPCH), the implemented COMSIC receiver with ICE exhibits a significant decrease in the required transmit signal energy per bit-to-background noise power spectrum density ratio (Eb/N0) at the average bit error rate (BER) of 10-3 (while the matched filter (MF)-based Rake receiver could not realize the average BER of 10-3 due to severe multiple access interference (MAI)). It is also found that the achieved BER performance at the average BER of 10-3 of the COMSIC receiver with the A/D converter quantization of 8 bits in the laboratory experiments is degraded by approximately 1.0 dB and 4.0 dB compared to the computer simulation results, when ΔEb/I0=-6 dB and -9 dB, respectively, due to the quantization error of the desired signal and path search error for the Rake combiner. Finally, we show that the required transmit Eb/N0 at the average BER of 10-3 of the third-stage COMSIC with ICE is decreased by approximately 0.3 and 0.5 dB compared to that of COMSIC with decision-feedback type channel estimation (DFCE) with and without antenna diversity reception, respectively.

The packaging hierarchy is not fixed structure. It can be changed depending on the packaging technology itself, and the number of hierarchy levels tends to decrease. In LSI-package technology including package-to-board interconnections, there were two evolutionary changes. The first evolution was from PTH to SMT, and the second evolution was from "Peripheral connections" to "Area-array connections. " These evolutions have been caused by ICs integration and application products requirements. Now, the third evolution appears to be in progress, which is from SCP to MCP or SIP. Although SoC has many remarkable features, it has been not applied for many systems contrary to expectations, and its limitations or issues have become clear. SIP is the answer for above SoC's issues. MCP can be considered to be primitive SIP. The purpose of MCP is making up the technology gap between SMT and SoC to address the issues. The targets of SIP are mainly the next two items. (1) Overcoming the interconnection crisis of SoC. (2) Opening new application fields in electronics. In order to achieve those targets, several consortiums in the world are doing research and developing core technologies.