The intermediate language (IL) modularizes a compiler into target processor independent and dependent parts, called the front-end and the back-end. By adding a new back-end, it is possible to port existing software from one processor to another. This paper presents a new efficient approach to achieve multiple targeting to quite different architectures using different processors as well, by translating from one IL into other existing ILs. This approach makes it possible to reuse existing back-ends. It has been successfully applied to a commercial-scale project for porting public switching system software. Since the target ILs were not predictable in advance, we provided an abstract syntax tree (AST) with attributes accessible by abstract data type (ADT) interface to convey the source language information from our front-end to back-ends. It was translated into several ILs that were developed independently. These translations made the compiler available in a very short time for different cross-target platforms and on several workstations we needed. The structure of this AST and the mapping to these ILs are presented, and retargeting cost is evaluated.

This paper addresses the problem of multiple multicast in WDM networks. It presents three efficient algorithms to construct an optimal/sub-optimal multicast tree for each multicast and minimise the network congestion on wavelengths. The first two algorithm achieve an optimal network congestion for a specific class of networks whose all wavelengths are globally accessible and convertible at a unit cost. The third algorithm produces an approximation solution for the general case of WDM networks.

As wireless communication is penetrating every corner of the globe, the optimum design and accurate analysis of RF, power semiconductor devices become one of the biggest challenges in EDA and TCAD (Technology CAD) tool development. The performance gauge for these devices is quite different from that for either digital or analog devices aimed at small-signal applications in that the power gain, efficiency, and distortion (or the range of linearity) are the utmost design concerns. In this article, the methodology and mathematical foundation for numerical analysis of large signal distortion at the device simulation level are discussed. Although the harmonic balance (HB) method has long been used in circuit simulation for large signal distortion analysis, the implementation of the same method in device simulation faces daunting challenges, among which are the tremendous computational cost and memory storage management. But the benefits from conducting such a device level simulation are also obvious--for the first time, the impact of technology and structural variation of device on large signal performance can directly be assessed. The necessary steps to make the HB analysis feasible in device simulation are outlined and algorithmic improvement to ease the computation/storage burden is discussed. The applications of the device simulator for various RF power devices, including GaAs MESFETs and silicon LDMOS (lateral diffusion MOS) are presented, and the insight gained from such an analysis is provided.

With the progress of LSI technology, the electronic device size is presently scaling down to the nano-meter region. In such an ultrasmall device, it is indispensable to take quantum mechanical effects into account in device modeling. In this paper, we first review the approaches to the quantum mechanical modeling of carrier transport in ultrasmall semiconductor devices. Then, we propose a novel quantum device model based upon a direct solution of the Boltzmann equation for multi-dimensional practical use. In this model, the quantum effects are represented in terms of quantum mechanically corrected potential in the classical Boltzmann equation.

To design and develop user-oriented, flexible and distributed applications which can deal with various users' requirements, new technologies to manage, control and utilize the services of communication networks have to be provided. In this paper, the current challenges faced by large-scale distributed applications are discussed and a framework for the next generation network operation and management is presented on the basis of agent-based computing technologies. Examples of flexible distributed applications are presented to clarify the role of application-centric flexible network operation and management.

This paper discusses the implementation and cost- and performance- evaluations of a distributed processing network, called DONA-α, which is one of the possible physical networks mainly implementing connection-oriented public switched network functions corresponding to OSI layers 1 to 3. The first feature of the DONA-α network is that it separates a switching subsystem and a control subsystem of a conventional switching system and independently allocates them over distributed nodes as a switching node and a control node. Each DONA-α switching node is given a much smaller switching capacity than the switching subsystem of the conventional switching system and is located near subscribers. In contrast, each DONA-α control node has much higher performance than the control subsystem of the conventional switching system. This allows a large number of switching nodes to share the same control node, which controls their connection setups. This separation provides the network with greater flexibility and allows more effective utilization of network resources, such as control processors, switching fabrics, and transmission links, than ever before. The second feature of DONA-α is that it provides a network with network-wide distribution transparency. This allows network resources including software such as databases and application programs to be shared and therefore to be utilized in the network more easily and more efficiently. The results of a network performance simulation and cost calculation confirm the viability of the DONA-α network.

Even though BiCMOS process has an ability to make both BJT and MOSFET on single-chip, only BJT has been used for BiCMOS Si-MMIC LNA because of its low noise and high gain performance under low d. c. supply power. But the distortion performance of BJT should be improved for the receiver applications in some wireless systems. In this paper, intermodulation distortion characteristics comparison is carried out between BJT and MOSFET fabricated in the same BiCMOS process by the analysis based on the simplified transistor models with extracted device parameters. The analytical result shows that MOSFET has lower intermodulation distortion characteristics compared with BJT, and the result is evaluated by the measurements. In order to obtain both low distortion and low noise characteristics, a two-stage Si-MMIC LNA is developed by using BJT as the 1st stage and MOSFET as the 2nd stage of LNA. The fabricated LNA performs NF of 2.45 dB, gain of 19.3 dB, IIP3 of14.6 dBm and OIP3 of 4.7 dBm under 3 V/7.2 mA d. c. supply power.

Frequency chirping induced in an electorabsorption (EA) modulator can degrade transmission performance because of the chromatic dispersion of fiber. This letter studies the frequency chirping in an EA modulator from the viewpoint of the influence of the modulation bandwidth. Both simulations and experiments, in which fiber transmission was carried out applying modulation signals of different bandwidths to an EA modulator, show that a large bandwidth causes small degradation in the transmission performance. This result is attributed to the short chirping time that occurs when a large bandwidth signal is applied.

Second harmonic signal feedback technique is applied to an HBT power amplifier for Wide-band CDMA (W-CDMA) mobile communication system to improve its linearity and efficiency. This paper describes the feedback effect of the 2nd harmonic signal from the output of the amplifier to the input on the 3rd order intermodulation distortion (IMD) products and Adjacent Channel leakage Power (ACP) of the power amplifier. The feedback amplifier, using an InGaP/GaAs HBT with 48 fingers of 3 20 µ m emitter, exhibits a 10 dB reduction in the level of the 3rd order IMD products. In addition, an ACP improvement of 7 dB for the QPSK modulation signal with a chip rate of 4.096 Mcps at 1.95 GHz was realized. As a result, the amplifier achieves a power-added efficiency of 41.5%, gain of 15.3 dB, and ACP of 43.0 dBc at a 5 MHz offset frequency and output power of 27.5 dBm. At the output power of 28 dBm, the power-added efficiency increases to 43.3% with an ACP of 40.8 dBc.

In universal personal telecommunication (UPT) environments, UPT networks retain information related to incall/outcall registration in UPT user service profiles in order to provide incoming UPT calls for UPT users in any location who have registered at a terminal. As UPT networks support incall registration, terminal users can be different from terminal owners, and several UPT users can register for incoming calls on a single terminal. Therefore, appropriate third-party protection procedures are needed to protect the rights of terminal owners. A terminal profile database can be used to store information regarding terminal states and incall UPT users registered on a terminal in order to enable third-party protection procedures. In order to manage information within both the terminal profile and the service profile, we propose a request-based scheme for incall registration/deregistration of UPT users and incall registration resets of terminal owners. We evaluate the performance of the scheme in terms of; 1) total cost and, 2) the number of terminal profile accesses per unit time for a terminal.

Technologies used to characterize and compensate nonlinearities in microwave power amplifiers are discussed. First, a complex power series representation that allows both amplitude and phase nonlinearities to be dealt with simultaneously is proposed, and in order to estimate the 3rd-order complex coefficient phase of practical amplifiers, two kinds of experimental measurement methods are proposed. Next, the fundamental circuit configuration of IF cuber predistortion linearizer that compensates 3rd-order intermodulation distortion is derived from a nonlinear analysis using complex power series representation. Two practical cuber predistorters for the 6-GHz TWTA and the 800-MHz FET-PA are demonstrated. Moreover, the unique nonlinear compensation technology of side-band inversion is introduced for microwave relay system using TWTAs. Finally, the self-adjusting feed-forward (SAFF)-PA developed for digital cellular base stations is reviewed.

In this paper we present a complete methodology for efficient electro-mechanical characterization of a CMOS compatible MEMS technology. Using an original test structure, the so-called "U-shape cantilever beam," we are able to determine all mechanical characteristics of force sensors constituted with elementary beams in a given technology. A complete set of electro-mechanical relations for the design of Microsystems have also been developed.

Auctions are a critical element of the electronic commerce infrastructure. But for real-time applications, auctions are a potential problem - they can cause significant time delays. Thus, for most real-time applications, sealed-bid auctions are recommended. But how do we handle tie-breaking in sealed-bid auctions? This paper analyzes the use of multi-round auctions where the winners from an auction round participate in a subsequent tie-breaking second auction round. We perform this analysis over the classical first-price sealed-bid auction that has been modified to provide full anonymity. We analyze the expected number of rounds and optimal values to minimize communication costs.

This paper proposes a newly developed dual-frequency antenna for 800 MHz and 1500 MHz band use. A uniformly spaced array configuration, originally designed for a 800 MHz analog system, is extended to yield dual frequencies operations. An important characteristic of a base station antenna is low sidelobe level in order to suppress inter-cell interference. In the case of a uniformly spaced array configuration, sidelobe levels are increased by the emergence of grating lobes at higher frequencies. Electrical beam tilt also degrades the sidelobe level. As does the change in the excitation coefficients of the array elements at higher frequencies. These three factors are studied theoretically to yield practical sidelobe levels. One more important beam characteristic is the sector beam in the horizontal plane. The same beam width in two frequency bands is achieved by designing the novel reflector shape and determining the proper array element positions in front of the reflector. Practical antenna characteristics are confirmed by designing, manufacturing, and testing a base station antenna.

This paper reports on the use of microelectronic test structures to characterise a novel fabrication technique for thin-film electronic circuit boards. In this technology circuit tracks are formed on paper-like substrates by depositing films of a metal-loaded ink via a standard lithographic printing process. Sheet resistance and linewidth for both horizontal and vertical lines are electrically evaluated and these compared with optical and surface profiling measurements.

This paper presents the technologies for over-40-Gbit/s operation of InP-based HEMT ICs for future optical communication systems. High-speed interconnection using low-permittivity benzocyclobutene (BCB) film as an inter-layer insulator decreases interconnection delay and results in high-speed operation of digital circuits. A static frequency divider and a 2 : 1 multiplexer using this novel interconnection demonstrate 49-GHz and 80-Gbit/s operation, respectively. Ultrahigh-speed digital/analog ICs fabricated using the HEMTs were used in 40 Gbit/s optical transmission experiment and showed good bit-error-rate performance. A novel two-step recess process for gate recess etching considerably improves the performance of InP-based HEMTs and is found to be promising for future ultrashort-gate devices.

In this paper, we briefly review the recent research on CMOS gigahertz-rate communication circuits. Then, we describe design innovations we have made to overcome limitations on communication speed. Using 0. 25-µm CMOS technology, we developed a 4.25-Gb/s Fibre Channel transceiver that features an asynchronous tree-type 1 : 8 demultiplexer and an 8-bit-to-10-bit frequency-conversion architecture. And using 0. 15-µm CMOS technology, we developed an 11. 8-GHz frequency divider that introduces the novel idea of a hysteresis-controlled latch (HC-latch). With these results, we discuss high-speed LSI design issues and future prospects.

This paper surveys the results of various studies on 3-D image coding. Themes are focused on efficient compression and display-independent representation of 3-D images. Most of the works on 3-D image coding have been concentrated on the compression methods tuned for each of the 3-D image formats (stereo pairs, multi-view images, volumetric images, holograms and so on). For the compression of stereo images, several techniques concerned with the concept of disparity compensation have been developed. For the compression of multi-view images, the concepts of disparity compensation and epipolar plane image (EPI) are the efficient ways of exploiting redundancies between multiple views. These techniques, however, heavily depend on the limited camera configurations. In order to consider many other multi-view configurations and other types of 3-D images comprehensively, more general platform for the 3-D image representation is introduced, aiming to outgrow the framework of 3-D "image" communication and to open up a novel field of technology, which should be called the "spatial" communication. Especially, the light ray based method has a wide range of application, including efficient transmission of the physical world, as well as integration of the virtual and physical worlds.

This paper reviews the hyper-media photonic information network (HM-PIN) concept as a candidate of innovative future networks based on photonic technologies. The HM-PIN having a universal network interface integrates a variety of information services: telecommunications, newspapers, magazines, TV broadcasts and the growing collection of information servers. This network fundamentally offers three items: (1) bi-directional real-time channels with 10-Mbit/s-class or higher bit rate, (2) multipoint connections including multicasting/broadcasting, (3) high accessibility to information. These items are derived from the constraints of the conventional telephone networks and the Internet. By applying photonic technologies, the HM-PIN can be implemented as follows: The local network (the service platform) of the HM-PIN can be achieved by using a wavelength-division-multiplexing (WDM) broadcast-and-select (B&S) architecture that offers broadband multipoint connections (one-to-many, many-to-many) based on an inherent full-mesh topology. The WDM B&S local network will be able to support 10,000 to 100,000 channels (each with 10-Mbit/s or more bandwidth) by using optical and electrical multiplexing techniques. The backbone network can be constructed by combining photonic asynchronous transfer mode (ATM) switching systems and WDM transmission systems (including cross-connects). Two deployment scenarios of the HM-PIN (cost-oriented and service-oriented deployment scenarios) are also described for smoothly introducing the HM-PIN even before the cost issue is solved. The HM-PIN based on photonic technologies will be a future network service platform that greatly enhances communication services.

This paper describes the implementation and demonstration of local networks for the hyper-media photonic information network (HM-PIN), a candidate for the information service platform offering broadcast and telecommunication services. In addition, the feasibility of the HM-PIN is also demonstrated using prototype local network systems. This local network adopts architecture based on wavelength-division-multiplexing (WDM) and broadcast-and-select (B&S) switching, and supports all HM-PIN services except inter-local-network communication. The major issues of this proposed network are the technologies that support many broadcast channels and reduce channel selection cost. This paper also considers the combination of WDM technology and three alternatives: electrical TDM, subcarrier multiplexing (SCM or electrical FDM), and optical TDM (O-TDM). Three 128 ch (8 wavelengths 16 channels) WDM B&S prototype systems are built to demonstrate the feasibility of the proposed HM-PIN. In WDM/SCM, 30 and 20 Mb/s channels are realized as 16-QAM and 64-QAM, and 155 Mb/s channels are realized by WDM/TDM. Moreover, these three prototypes were connected to form a small HM-PIN and applications such as video distribution and IP datagram cut-through are demonstrated. Furthermore, the delay and throughput of the HM-PIN are evaluated by connecting a local network to a 200-km WDM-ring backbone network. Our discussions and demonstrations confirm the impact and feasibility of the proposed hyper-media photonic information network.