In this paper, a novel content addressable memory (CAM) structure is proposed to improve the performance of a static divided word matching (SDWM) CAM. In the SDWM CAM, a small pmos has to be used to keep a noise margin, but it degrades performance significantly. To resolve this problem, a conditional driver is introduced in the proposed serial-parallel CAM. Performance is improved by 28.0% without additional power consumption at a cost of about 5.6% increased area when the total bit number is 32 with four series bits and 30% of VDD is allowed as noise.

In the context of multiple constant multiplication (MCM) design, we propose a novel common sub-expression elimination (CSE) algorithm that models the optimal synthesis of coefficients into a 0-1 mixed-integer linear programming (MILP) problem with a user-defined generic logic depth constraint. We also propose an efficient solution space, which combines all minimal signed digit (MSD) representations and the shifted sum (difference) of coefficients. In the examples we demonstrate, the combination of the proposed algorithm and solution space gives a better solution comparing to existing algorithms.

Functional and formal verification are important methodologies for complex mixed-signal design validation. However the industry is still verifying such systems by pure simulation. This process lacks on error localization and formal verifications methods. This is the existing verification gap between the analog and digital blocks within a mixed-signal system. Our approach improves the verification process by creating temporal properties named mixed-signal assertions which are described by a combination of digital assertions and analog properties. The proposed method is a new assertion-based verification flow for designing mixed-signal circuits. The effectiveness of the approach is demonstrated on a Σ/Δ-converter.

Testing PLLs (phase-locked loops) is becoming an important issue that affects both time-to-market and production cost of electronic systems. Though a PLL is the most common mixed-signal building block, it is very difficult to test due to internal analog blocks and signals. In this paper, we propose a new PLL BIST (built-in self test) using the distorted frequency detector that uses only internal digital signals. The proposed BIST does not need to load any analog nodes of the PLL. Therefore, it provides an efficient defect-oriented structural test scheme, reduced area overhead, and improved test quality compared with previous approaches.

Testing is a critical stage in integrated circuits production in order to guarantee reliability. The complexity and high integration level of mixed-signal ICs has put forward new challenges to circuit testing. This paper describes an oscillation-based combined self-test strategy for the analog portion and analog-to-digital converters (ADCs) in integrated mixed-signal circuits. In test mode, the analog portion under test is reconfigured into an oscillator, generating periodic signals as the test stimulus of ADC. By analyzing the A/D conversion results, a histogram test of ADC can be performed, and the oscillation frequency as well as amplitude can be checked, and in this way the oscillation test of the analog portion is realized simultaneously. For an analog benchmark circuit combined with an ADC, triangle oscillation and sinusoid oscillation schemes are both given to test their faults. Experimental results show that fault coverage of the analog portion is 92.2% and 94.3% in the two schemes respectively, and faults in the ADC can also be tested.

This paper includes different approaches for analysis of a thin-wire antenna in the presence of de-ionized water box at different temperatures as a high-permittivity three-dimensional dielectric body. In continuation with the previous work of authors, first, the coupled tensor-volume/line integral equations is solved by using Galerkin-based moment method (MoM) consisting of a combination of entire-domain and sub-domain basis functions including three-dimensional polynomials with different degrees. Then, the accuracy of such MoM, specifically for a high-permittivity dielectric scatterer, is substantiated by comparing its numerical results with that of FDTD method and some experimental data.

We have developed the fabrication process, the circuit design technology, and the cryopackaging technology for high-Tc single flux quantum (SFQ) devices with the aim of application to an analog-to-digital (A/D) converter circuit for future wireless communication and a sampler system for high-speed measurements. Reproducibility of fabricating ramp-edge Josephson junctions with IcRn products above 1 mV at 40 K and small Ic spreads on a superconducting groundplane was much improved by employing smooth multilayer structures and optimizing the junction fabrication process. The separated base-electrode layout (SBL) method that suppresses the Jc spread for interface-modified junctions in circuits was developed. This method enabled low-frequency logic operations of various elementary SFQ circuits with relatively wide bias current margins and operation of a toggle-flip-flop (T-FF) above 200 GHz at 40 K. Operation of a 1:2 demultiplexer, one of main elements of a hybrid-type Σ-Δ A/D converter circuit, was also demonstrated. We developed a sampler system in which a sampler circuit with a potential bandwidth over 100 GHz was cooled by a compact stirling cooler, and waveform observation experiments confirmed the actual system bandwidth well over 50 GHz.

In this paper, we consider a method to enhance the throughput of HSDPA systems in the mixed traffic scenario. A channel-dependent adaptive delay barrier (DB) function is proposed to maximize throughput of best-effort (BE) traffic while satisfying the delay latency of voice over internet protocol (VoIP) service. Simulations show that the proposed channel-adaptive DB function raises the throughput of BE traffic service by 30% compared to the conventional scheme, without degrading the capacity of VoIP service over HSDPA system.

In this paper, we present a novel force-directed method for automatically drawing intersecting compound mixed graphs (ICMGs) that can express complicated relations among elements such as adjacency, inclusion, and intersection. For this purpose, we take a strategy called unified simplification that can transform layout problem for an ICMG into that for an undirected graph. This method is useful for various information visualizations. We describe definitions, aesthetics, force model, algorithm, evaluation, and applications.

Quality-of-service (QoS) is essential for multimedia applications, such as video-conferencing and voice over IP (VoIP) services, in wireless mesh networks (WMNs). A consequence of many clients accessing the Internet via the same backhaul is that throughput depends on the number of hops from the backhaul. This spatial bias problem is formulated as a mixed-integer nonlinear programming problem that considers end-to-end delay in terms of gateway selection, least-hop and load-balanced routing, and link capacity constraints. In this paper, we propose a routing algorithm for the network layer and a bandwidth allocation scheme for the medium access control (MAC) layer. The latter achieves fairness in both throughput and end-to-end delay in orthogonal mesh backbone networks with a distributed scheme, thereby minimizing the objective function. Our experiment results show that the proposed algorithm achieves throughput fairness, reduces end-to-end delay, and outperforms other general schemes and algorithms by at least 10.19%.

A new approach for solution of the Tensor-Volume Integral Equation (TVIE) using Galerkin-based moment method (MoM) for three-dimensional dielectric bodies is proposed. Two problems of plane wave scattering by a dielectric sphere and a thin-wire antenna in close proximity to a dielectric body are investigated. In both cases, cubic modeling is applied and a combination of entire-domain and sub-domain basis functions, including three-dimensional polynomial functions with different degrees is utilized for field expansion inside dielectric bodies. Power polynomial is adopted for this purpose and its property is discussed over the proposed mixed-domain MoM formulation. Numerical examples show that based on the proposed method, a relative fast algorithm and suitable accuracy are achieved compared with conventional MoM. The accuracy of the proposed method is verified by comparing it with the Mie theory, conventional MoM and the FDTD method.

Band connections employed in active cancellation circuits for effective reduction of digital substrate noise are proposed. An almost-odd-symmetrical noise characteristic is utilized for canceling out noises. Advancing this idea, interlaced connections of four bands are also proposed. Excess cancellation by those bands is more effective for noise reduction in a guard ring than a cancellation by two bands. Use of L-shaped bands on the basis of the interlaced connection suppresses the noise more. Simulation and experimental results show that the proposed band connections reduce the noise.

In this paper, we have derived the new solution for the medium-frequency and the high-frequency ground wave propagation in a surface duct over mixed-paths. We have shown newly that the solution for the ground wave propagation in a standard atmosphere can be obtained directly from the solution for the surface duct problem by applying the analytic continuation from the negative equivalent radius of curvature of the earth to the positive one. Through the theoretical and experimental studies, it is confirmed that the radio wave propagating over the sea in the land-to-sea mixed-paths is enhanced by the recovery effect. It is clarified that the ground wave is also enhanced in the surface duct in a long range propagation. It is shown that the unexpected attenuation and the anomalous variation with distance are appeared in the propagation in the urban area due to the emergence of the slow-wave type trapped surface wave.

Various mixed-signal very-high-speed integrated circuits have been developed using InP DHBTs. These circuits have been designed for fiber-optic 43 Gbit/s transmissions applications. They include: on the transmitting side, a clocked driver and an EAM driver, as well as a PSBT/DQPSK precoder; on the receiving side, a sensitive decision circuit, a limiting amplifier and an eye monitor. System experiments made possible by these circuits include a 6 Tbit/s transmission on >6000 km distance.

Visualizing occluded objects is a useful applications of Mixed Reality (MR), which we call "see-through vision." For this application, it is important to display occluded objects in such a manner that they can be recognized intuitively by the user. Here, we evaluated four visualization methods for see-through vision that can aid the user to recognize occluded objects in outdoor scenes intuitively: "elimination of occluding objects," "ground grid," "overlaying model of occluding object," and "top-down view." As we used a new handheld MR device for outdoor see-through vision, we performed subjective experiments to determine the best combination of methods. The experimental results indicated that a combination of showing the ground grid, overlaying wireframe models of occluding objects, and top-down view to be optimal, while it was not necessary to display occluding objects for outdoor see-through vision with a handheld device, because users can see them with the naked eye.

Recently, system level design languages (SLDL), which can describe both hardware and software aspects of the design, are receiving attention. Mixed-signal extensions of SLDL enable current discrete-oriented SLDLs to describe and simulate not only digital systems but also digital-analog mixed-signal systems. The synchronization between discrete and continuous behaviors is widely regarded as a critical part in the extensions. In this paper, we present an event-driven synchronization mechanism for both timed and untimed system level designs through which discrete and continuous behaviors are synchronized via AD events and DA events. We also demonstrate how the synchronization mechanism can be incorporated into the kernel of SLDL, such as SpecC. In the extended kernel, a new simulation cycle, the AMS cycle, is introduced. Three case studies show that the extended SpecC-based system level design environment using our synchronization mechanism works well with timed/untimed mixed-signal system level description.

A new approach used to formulate to mixed-path propagation of surface wave is presented based on two main ingredients: the decomposition of electromagnetic fields and the introduction of equivalent electric (magnetic) currents adopted for convenience. The present method can be extended to obtain the corresponding results for the arbitrary incident wave excitation.

This paper clarifies a necessary condition and a sufficient condition for transmissibility for a given set of general sources and a given general broadcast channel. The approach is based on the information-spectrum methods introduced by Han and Verdu. Moreover, we consider the capacity region of the general broadcast channel with arbitrarily fixed error probabilities if we send independent private and common messages over the channel. Furthermore, we treat the capacity region for mixed broadcast channel.

In this paper we present a 3D adaptive nonlinear filter, namely the 3D adaptive CPWLN, based on the Canonical Piece Wise-Linear Network with an LMS L-filter type of adaptation. This filter is used to equalize nonlinear channel effect and remove impulsive/or mixed impulsive and Additive White Gaussian noise from video sequences. First, motion compensation is performed by a robust estimator. Then, a 3-D CPWLN LMS L-filter is applied. The overall combination is able to adequately remove undesired effects of communication channel and noise. Computer simulations on real-world image sequences are included. The algorithm yields promising results in terms of both objective and subjective quality of the restored sequence.

We propose an accurate and efficient model of having an unbalanced differential line structure, where mode-conversion and frequency dependent loss effects are considered in above the GHz frequency range. To extract model parameters of the proposed unbalanced differential line model, we measured s-parameters of test patterns using a 2-port VNA and defined a new type of mixed-mode s-parameter. The model parameters were obtained and are described for various types of the unbalanced differential line structures. Finally, the validity of the proposed model and the model parameters were successfully confirmed by a series of time-domain measurements and a lattice diagram analysis.