Signal Distribution Network Research Articles

Influence of process parameter variations on the signal distribution behavior of wafer scale integration devices

With decreasing geometries of MOS transistors in VLSI devices, the influence of fluctuations of process parameters during manufacturing will become more and more important, because process tolerances are not proportionally scaled to geometries. These fluctuations result in a performance spread of the devices produced by a certain process. For instance the clock rate of a microprocessor as a typical performance indicator, can vary in a wide range. One of the key issues of the implementation of circuits using wafer scale integration technologies is the synchronous distribution of signals, either clock, data or control over a large area of silicon. Fluctuations of process parameters can have a major influence on the performance of these devices. In the following paper, an efficient method for accurate prediction of the performance spread of integrated circuits is discussed and demonstrated by simulations. All the simulations are verified by measurements on a test-circuit with a huge number of test devices. The method is applied to different signal distribution networks of wafer scale integration devices to show the sensitivity of performance to these variations.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

One dimensional scaling of 100 ridge waveguide amplifiers

We have demonstrated the concept of scaling large numbers of laser diodes to achieve high power with good beam quality. We have achieved a system based on scaling 100 ridge waveguide amplifiers with a coherent optical signal distribution network and phase modulators on a 12.2 mm/spl times/4.4 mm chip called a unit cell. The unit cell delivers 1.63 W of CW power in the central lobe with diffraction-limited performance. A high performance cooler allows high power CW performance. A custom lens array and computer-controlled phase modulators allow the beam to be collimated with flat phase front. >

ISDN signal distribution network

The author discusses the ISDN Staged Transport System (STS). The STS illustrates how an ISDN network can be used as a flexible distribution medium for directing real-time signals over a WAN to a staged transport server. Although the signal feeds distributed by the STS application are audio voice grade circuits (VGCs), the architecture lends itself to other signal types, such as video. Moreover, ISDN bridges and routers allow the real-time communications infrastructure to distribute bulk recorded signals as well. Finally, the multimedia wide-area connectivity provided by ISDN allows an entire signal processing operation to be remoted, with receivers, storage, and mission control all managed from a single site (or multiple sites) on the network. While the STS application uses the user to user information element (UU-IE) to control signal processing on the edge of the ISDN network, the UU-IE could just as easily be used on the interior of the network by switch adjuncts to augment dialed number routing with intelligent-application-based routing. When combined with the rich set of commercially available applications available on many ISDN switches and adjuncts, sophisticated signal processing, distribution, and management networks could be rapidly configured and deployed with relative ease.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Optical interconnection and packaging technologies for advanced avionics systems

An optical backplane developed to demonstrate the advantages of high-performance optical interconnections and supporting technologies and designed to be compatible with standard avionics racks is described. The hardware demonstrates the three basic components of optical interconnects: optical sources, an optical signal distribution network, and optical receivers. Results from characterization and environmental tests, including a demonstration of the reliable transmission of serial data at a 1 Gb/s, are reported. >

Optimization of signal distribution networks using simulated annealing

The author discusses the use of simulated annealing for optimizing signal distribution networks consisting of multiplexers, switches, buses and end-devices or users. A linear algebraic approach is developed for application of simulated annealing to problems of this kind. The author shows how such an approach allows for the optimization of general capacity-constrained signal distribution networks containing multiple levels of demultiplexers, switches, and buses, with linear and nonlinear objective functions. Examples include both linear and nonlinear objective functions. >

Design and application of a GaAs digital RF memory chip

The design and performance of a GaAs integrated memory/logic chip designed for digital RF memory (DRFM) applications is described. This chip, called a programmable delay-line element (PDLE), implements the basic DRFM storage and delay functions. The RAM-with-logic configuration combines a 4-kb static RAM with 750 logic gates, providing on a single chip the components for storage, address generation, demultiplexing, multiplexing, and control functions normally provided by a variety of separate chips. A distributed control organization, where the chip is configured to provide as outputs all the signals required as inputs to another identical chip, is used. Chips cascaded into strings implement the programmable delay lines required for DRFM systems. Problems associated with complex signal distribution networks are avoided since, within a string, signal distribution requires only local interconnections between adjacent chips. Correct operation of all functions was demonstrated in a four-chip string which provides a total memory capacity of 16 kb. The maximum sampling rate was 800 MHz, and power dissipation was approximately 2 W per chip. >

The PDMS as a focal point for distributed patient data.

Distributed data links are essential requirements for a successful patient data management system (PDMS). These links funnel clinically needed data into bedside ICU workstations. We have constructed four data links which acquire most of the objective data required for direct patient care. Data from bedside monitors is acquired via a standard HP Signal Distribution Network. Urine volumes and core bladder temperatures are acquired over a link to 20 electronic urimeters. Clinical laboratory data is obtained over an HP General Purpose Data Link (GPDL) to a VAX 11/785 laboratory system. Blood gas data is obtained over a second GPDL link to a DEC 11/23 computer. The ICU staff is notified of incoming lab results with bedside video messages. Combined with automated calculations, these data links eliminate thousands of data entry keystrokes daily and allow the PDMS to serve as the focal point for real-time patient care.

FOCAS–A NEW LOOK IN COMBAT SYSTEM SIGNAL TRANSMISSION

ABSTRACTThis article introduces the concept of a truly Universal Signal Distribution Network. The emergence of fiberoptic technology as a viable signal transmission medium now gives the Navy the opportunity to use Fiber Optic Cabling and Switching (FOCAS) to implement a universal network. A FOCAS Network can handle all present or future shipboard signal distribution architectures such as point‐to‐point or data bus. Furthermore, compared to existing cable installations, this network offers lower cost through reduction of the number of cables, weight, and volume, freedom from interference and EMP effects, increased redundancy, and higher operational flexibility. In addition, it will easily satisfy all future expansion or changes in signal distribution by providing at least a ten fold increase in data rate capacity over existing electrical cabling. This last feature alone holds the potential for allowing upgrading and conversion of modern combat systems without need for adding new cabling in the ship.Along with the introduction of the concept of a Universal FOCAS network and its practical benefits and capabilities, this article presents a trade‐off between the Radar Data Distribution Network on the FFG and an analogous FOCAS network. Though far from optimized, the resultant FOCAS network shows that the conversion of existing shipboard networks to FOCAS is straightforward and provides a reduction of at least 90% in cable volume and weight and lower cost in cable purchase and installation.

Design of a Switched Broad-Band Communications Network for Interactive Services

The congestion in broad-band communications networks resulting from the increased demand for interactive services is considered. It is shown that services such as a video library could not be provided to the majority of subscribers in a conventional CATV network. A design is developed for a space division multiplex broad-band network which can be expanded at minimum cost to meet an increasing demand for interactive services. The network contains two signal distribution networks: a cablecast system similar to the Rediffusion system, and a switched communication network providing point-to-point circuits for both one-way and two-way services. All broad-band signals are transmitted to the subscribers in the 1- to 10-MHz spectrum, permitting the use of twisted pair video cables and a minimum number of cable amplifiers. The broad-band cable network (BCN) is organized around 15 local switching exchanges and one central exchange. Multipoint switches in local exchanges under wired-logic circuit control connect individual subscriber communication lines to any channel. Crosspoint matrix switching groups in the local and central exchanges connect communication circuits in the broad-band communication network under programmed computer control. This network is accessed via links terminating on one channel of the multiposition switches. Per-subscriber costs are estimated to be 190 dollars for a cablecast system serving 3800 subscribers. Additional expenditures per subscriber of 40 dollars for fixed costs and 40 dollars for variable costs would provide interactive services. The range of interactive services provided would be extremely flexible, including both one-way video library service and point-to-point two-way communications.