The smart vision chip has a large potential for application in general purpose high speed image processing systems. In order to fabricate smart vision chips including photo detector compactly, we have proposed the application of three dimensional LSI technology for smart vision chips. Three dimensional technology has great potential to realize new biologically inspired systems inspired by not only the biological function but also the biological structure. In this paper, we describe our three dimensional LSI technology for biologically inspired circuits and the design of smart vision chips.

Reverse link performance analyses of single-code (SC) and multi-code (MC) CDMA systems in multipath fading environments are presented. The degree of orthogonality loss among multiple spreading code channels is characterized by introducing the orthogonality factor. This factor depends on the multipath delay power profiles of the propagation channel and the number of paths resolved at a Rake receiver. The link capacity and the signal power of both CDMA systems are then analyzed according to varying system parameters, including spreading bandwidth, traffic load, the orthogonality factor, and the number of spreading codes assigned to a user. Analytical results show that the SC-CDMA system provides a larger link capacity and MC users require more power than SC users. The dominant parameters affecting the performance difference are the spreading bandwidth and multipath delay power profiles.

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.

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.

This paper describes performance enhancement of high-resolved delay time estimation by pattern diversity of wheel-shaped dipole antennas for the MUSIC algorithm. We propose that the wheel-shaped dipole antennas are used to average covariance matrices weightedly with their pattern diversity without decreasing the matrix dimension and to obtain freedom of selecting sweeping frequencies. It is numerically confirmed that the wheel-shaped dipole antennas can be used to enhance capability of the delay time estimation.

Wavelet based image compression is getting popular due to its promising compaction properties at low bitrate. Zerotree wavelet image coding scheme efficiently exploits multi-level redundancy present in transformed data to minimize coding bits. In this paper, a new technique is proposed to achieve high compression by adding new zerotree and significant symbols to original EZW coder. Contrary to four symbols present in basic EZW scheme, the modified algorithm uses eight symbols to generate fewer bits for a given data. Subordinate pass of EZW is eliminated and replaced with fixed residual value transmission for easy implementation. This modification simplifies the coding technique as well and speeds up the process, retaining the property of embeddedness.

The VHF broadband radio interferometry operated from 25 MHz to 250 MHz has been developed for observing lightning discharge progression. The lightning images are derived by sensing the electromagnetic-waves which are radiated during the discharges. The perpendicular baseline geometry provides the angular locations (azimuth and elevation) of lightning radiation sources. The lightning observations have been conducted in the Hokuriku District in 1999. The station consisted of three broadband antennas and an electric field antenna as well as a GPS receiver. The system was able to reconstruct lightning discharge channels in two-spatial dimensions and in time sequence. As one of the observation results, an upward negative cloud-to-ground lightning flash will be presented.

In this paper, we examine the polarimetric characteristics and the potential of the coherent decomposition in polarimetric synthetic aperture radar (SAR) interferometry. Coherent scattering decomposition based on the coherence optimization can separate effective phase center of different scattering mechanisms and can be used to generate canopy digital elevation model (DEM). This decomposition is applied to a simplified stochastic scattering model such as forest canopy. However, since the polarimetric characteristics are not well understood when the decomposition is carried out, we investigate its characteristics and potential using polarimetric entropy-alpha and three-component scattering matrix decomposition. The results show that the first and third components correspond to the lower and upper layer, respectively, in ideal case. In this investigation, SIR-C/X-SAR data of the Tien Shan flight-pass are used.

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.

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.

This paper proposes a new method to recover the sign of local Gaussian curvature from multiple (more than three) shading images. The information required to recover the sign of Gaussian curvature is obtained by applying Principal Components Analysis (PCA) to the normalized irradiance measurements. The sign of the Gaussian curvature is recovered based on the relative orientation of measurements obtained on a local five point test pattern to those in the 2-D subspace called the eigen plane. Using multiple shading images gives a more accurate and robust result and minimizes the effect of shadows by allowing a larger area of the visible surface to be analyzed compared to methods using only three shading images. Furthermore, it allows the method to be applied to specular surfaces. Since PCA removes linear correlation among images, the method can produce results of high quality even when the light source directions are not widely dispersed.

This paper presents an application-specific, heterogeneous multiprocessor synthesis system, named HeMPS, that combines a form of Evolutionary Computation known as Differential Evolution with a scheduling heuristic to search the design space efficiently. We demonstrate the effectiveness of our technique by comparing it to similar existing systems. The proposed strategy is shown to be faster than recent systems on large problems while providing equivalent or improved final solutions.

This paper gives an overview of recent progress in radar polarimetry and radar polarimetric interferometry. Both techniques are of special importance for the inversion of physical scatterer parameters from radar remote sensing data. A unified treatment of polarisation effects in radar polarimetry and polarimetric interferometry based on eigenvalue processing is addressed providing a link between signal processing techniques and coherent electromagnetic models for random media scattering. In this context, the main applications of polarimetry in radar remote sensing such as single and multi-frequency polarimetric classification, the estimation of surface roughness and moisture content and vegetation structure estimation are reviewed.

As LSIs are two-dimensional structures, the number of external pins increases at a lower rate than the corresponding increase in the number of gates on the LSI. Therefore, the number of flip-flops on a scan path increases as the density of gates on LSIs rises, resulting in longer test application times. In this paper, three novel DFT strategies aimed at reducing test application time are proposed. DFT strategy 1 is a full scan design method with test point insertion, DFT strategy 2 is a partial scan design method, and DFT strategy 3 is a partial scan design method with test point insertion. Experimental results show that these DFT strategies reduced the test application times by 45% to 82% compared with conventional full scan design methods.

In this letter, blind adaptive H multiuser detection is developed by employing a generalized sidelobe canceler (GSC) with and without subweight partition scheme. It is shown that the adaptive H algorithm with subweight approach has the advantages of fast convergence speed, insensitivity of dynamic estimate error, and suitability for arbitrary ambient noise over the conventional H and the RLS-based adaptive algorithms.

In this paper, we present a new signal frequency estimation method based on the sinusoidal additive synthesis model. In the proposed method, frequencies in both the signal and noise are estimated with several delay times by using an expanded linear prediction (LP) method, and assuming that the signal is stationary and noise is unstationary in short record length. Frequencies in the signal are extracted according to their dependence on different delays. The frequency estimation can be accomplished with short record length even in the case where the number of frequency components in the signal is unknown. And it is capable of estimating the frequencies of a signal in the presence of noise. Furthermore, the proposed method estimates the parameters with less computation and high estimation accuracy. Simulation results are provided to confirm the effectiveness of the proposed method. The comparison of estimation accuracy between the proposed method and the analysis by synthesis (ABS) method is shown with the corresponding Cramer-Rao lower bound. And the frequency resolution of this method is also shown.

In this paper, a design of Programmable Logic Device (PLD) and a synthesis approach are proposed. Our PLD is derived from traditional Programmable Logic Array (PLA). The key extension is that programmable AND devices in PLA is replaced by Look-Up Tables (LUTs). A series of cascaded LUTs in the array can generate more complex terms, which we call generalized complex terms (GCTs), than product terms. In order to utilize the capability, a synthesis approach to map a given function into the array is also proposed. Our approach generates a expression of the sum of GCTs aiming to minimize the number of terms. A number of experimental results demonstrate that the number of terms for our PLD generated by our approach is 14.9% fewer than that by an existing approach. We design our PLD based on a fundamental unit named nGCT cell which can be used as LUTs in multiple sizes or random access memories. Implementation of the PLD based on a fundamental unit named nGCT cell which can be used as LUTs or random access memories is also described.

A system level approach for a memory power reduction is proposed in this paper. The basic idea is allocating frequently executed object codes into a small subprogram memory and optimizing supply voltage and threshold voltage of the subprogram memory. Since large scale memory contains a lot of direct paths from power supply to ground, power dissipation caused by subthreshold leakage current is more serious than dynamic power dissipation. Our approach optimizes the size of subprogram memory, supply voltage, and threshold voltage so as to minimize memory power dissipation including static power dissipation caused by leakage current. A heuristic algorithm which determines code allocation, supply voltage, and threshold voltage simultaneously so as to minimize power dissipation of memories is proposed as well. Our experiments with some benchmark programs demonstrate significant energy reductions up to 80% over a program memory which does not employ our approach.

In this paper, we propose a unified high-radix division algorithm for high-speed signal and data processing applications, and present the design and evaluation of high-radix parallel dividers based on the proposed algorithm. By prescaling the input operands and converting some significant digits of a partial remainder into non-redundant representation, the quotient digit can be obtained directly from the partial remainder without using quotient digit selection tables. Performance evaluation shows that the proposed radix-4 and radix-8 divider architectures achieve faster computation with the same level of hardware complexity than the binary counterparts. We also show an experimental fabrication of a radix-4 divider chip in 0.35 µm CMOS technology.

Hardware/software partitioning is one of the key processes in a hardware/software cosynthesis system for digital signal processor cores. In hardware/software partitioning, area and delay estimation of a processor core plays an important role since the hardware/software partitioning process must determine which part of a processor core should be realized by hardware units and which part should be realized by a sequence of instructions based on execution time of an input application program and area of a synthesized processor core. This paper proposes area and delay estimation equations for digital signal processor cores. For area estimation, we show that total area for a processor core can be derived from the sum of area for a processor kernel and area for additional hardware units. Area for a processor kernel can be mainly obtained by minimum area for a processor kernel and overheads for adding hardware units and registers. Area for a hardware unit can be mainly obtained by its type and operation bit width. For delay estimation, we show that critical path delay for a processor core can be derived from the delay of a hardware unit which is on the critical path in the processor core. Experimental results demonstrate that errors of area estimation are less than 2% and errors of delay estimation are less than 2 ns when comparing estimated area and delay with logic-synthesized area and delay.