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IBM Journal of Research and Development

Issue 2 • Date March 1985

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Displaying Results 1 - 11 of 11
  • Microprocessors in brief

    Publication Year: 1985 , Page(s): 110 - 131
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (2601 KB)  

    This paper presents a tutorial overview of the past, present, and future of microprocessors and describes the key elements of their structure and operation. It is intended to serve as a technical introduction to the rapidly expanding field of microprocessor and microcomputer technology and to provide an overview of what these elements are, what they can do, and how they do it. The origin and evolution as well as the basic principles of operation are discussed. Several different types of microprocessor are considered and examples of their application in the solution of real-world problems are given. View full abstract»

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  • Architecture of a digital signal processor

    Publication Year: 1985 , Page(s): 132 - 139
    Cited by:  Papers (12)  |  Patents (3)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (886 KB)  

    A digital signal processor (DSP) is described which achieves high processing efficiency by executing concurrently four functions in every processor cycle: instruction prefetching from a dedicated instruction memory and generation of an effective operand, access to a single-port data memory and transfer of a data word over a common data bus, arithmetic/logic-unit (ALU) operation, and multiplication. Instructions have a single format and contain an operand, index control bits, and two independent operation codes called “transfer” code and “compute” code. The first code specifies the transfer of a data word over the common data bus, e.g., from data memory to a local register. The second determines an operation of the ALU on the contents of local registers. A fast free-running multiplier operates in parallel with the ALU and delivers a product in every cycle with a pipeline delay of two cycles. The architecture allows transversal-filter operations to be performed with one multiplication and ALU operation in every cycle. This is accomplished by a novel interleaving technique called ZIP-ing. The efficiency of the processor is demonstrated by programming examples. View full abstract»

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  • Signal processor chip implementation

    Publication Year: 1985 , Page(s): 140 - 146
    Cited by:  Papers (10)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1130 KB)  

    Very large microprocessors can now be integrated on a single chip; the integration eliminates packaging delays and is especially attractive for performance-oriented processors such as signal processors. This paper describes a semicustom signal processor chip designed jointly by the IBM France Essonnes and La Gaude laboratories. The logic is implemented from an optimized library of bipolar circuits. Layouts are compatible and designed to map data flow structures efficiently. Chip design time has been greatly reduced through the use of developed CAD tools tailored to our methodology. The design achieves twice the density that would be possible (with the same technology) with a masterslice. The chip's high performance has been verified with hardware; it provides enough computation power for 125 second-order filters with 8-kHz sampling of the input signal. View full abstract»

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  • Voice-excited predictive coder (VEPC) implementation on a high-performance signal processor

    Publication Year: 1985 , Page(s): 147 - 157
    Cited by:  Papers (4)  |  Patents (3)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1262 KB)  

    In this paper, we discuss the implementation of a medium-bit-rate linear prediction baseband coder on an IBM bipolar signal processor prototype having a high processing capacity. We show that the implementation of our algorithm requires a processing load of 5 MIPS, with a program size of 5K instructions. We then discuss the application of our coder in a normal telephone environment, which requires mu-law to linear PCM conversion and other signal processing functions such as voice activity detection, automatic gain control, echo control, and error recovery. Quality evaluation tests are also reported which show that this type of coder, operating at 7.2 kbps, allows the transmission of telephone speech with communications quality. Moreover, obtained intelligibility scores and speaker recognition levels are high enough to demonstrate that this coder is a good candidate for telephony applications such as digital trunk transmissions, satellite speech communications, secure voice communications, and audio distribution systems. View full abstract»

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  • Personal Instrument (PI)—A PC-based signal processing system

    Publication Year: 1985 , Page(s): 158 - 169
    Cited by:  Papers (7)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1174 KB)  

    The Personal Computer (PC) technology has seen an enormous growth in the last two years. Although increasingly viewed as a major productivity tool, the PC is likely to be limited for computation-intensive tasks such as telecommunications and improved human-factors I/O. At the same time, there has been another evolving technology—VLSI realization of general-purpose signal processor (SP) engines which are capable of boosting the performance levels of standard PCs by almost two orders of magnitude. With SPs in PCs, we now see tremendous opportunities for distributing computation-intensive tasks away from high-performance mainframe computers; previously formidable tasks such as speech coding and recognition, pattern and scene analysis, spectral analysis, high bit-rate communication, and the like are now all computable by utilizing a single VLSI module embedded in any standard personal computer. This combination of a general-purpose CPU and superfast real-time coprocessor is likely to be key to the future functions and success of advanced workstations. A signal processing subsystem with real-time data acquisition and control capabilities has been developed for the IBM PC at the IBM Thomas J. Watson Research Laboratory and is the topic of this paper. View full abstract»

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  • An approach to DFT calculations using standard microprocessors

    Publication Year: 1985 , Page(s): 170 - 176
    Cited by:  Papers (5)  |  Patents (1)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (722 KB)  

    The use of the DFT as an everyday tool is now commonplace, principally due to advances in hardware technology. Special-purpose VLSI chips for signal processing are available. In this paper, we describe an approach which marries the Winograd Fourier Transform Algorithm (WFTA) with a state-of-the-art 16-bit general-purpose microprocessor for the purpose of DFT calculation. The heart of the approach is the real-input 240-point WFTA, which has been carefully optimized for time and space. In particular, an implementation for the 10-MHz M68000 executes in 10.8 ms. A simple hardware module is described which implements the optimized software. The use of the module for the inverse transform and for the complex case is also discussed. Advantages to the approach taken in this paper are the low cost/performance ratio and the general-purpose nature of the system that allows many non-signal-processing functions to be performed by the microprocessor. View full abstract»

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  • Image processing applications for geologic mapping

    Publication Year: 1985 , Page(s): 177 - 187
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1333 KB)  

    The use of satellite data, particularly Landsat images, for geologic mapping provides the geologist with a powerful tool. The digital format of these data permits applications of image processing to extract or enhance information useful for mapping purposes. Examples are presented of lithologic classification using texture measures, automatic lineament detection and structural analysis, and use of registered multisource satellite data. In each case, the additional mapping information provided relative to the particular treatment is evaluated. The goal is to provide the geologist with a range of processing techniques adapted to specific mapping problems. View full abstract»

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  • Parameter reduction and context selection for compression of gray-scale images

    Publication Year: 1985 , Page(s): 188 - 193
    Cited by:  Papers (43)  |  Patents (14)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (809 KB)  

    In the compression of multilevel (color or gray) image data, effective compression is obtained economically by judicial selection of the predictor and the conditioning states or contexts which determine what probability distribution to use for the prediction error. We provide a cost-effective approach to the following two problems: (1) to reduce the number of coding parameters to describe a distribution when several contexts are involved, and (2) to choose contexts for which variations in prediction error distributions are expected. We solve Problem 1 (distribution description) by a partition of the range of values of the outcomes into equivalence classes, called buckets. The result is a special decomposition of the error range. Cost-effectiveness is achieved by using the many contexts only to predict the bucket (equivalence class) probabilities. The probabilities of the value within the bucket are assumed to be independent of the context, thus enormously reducing the number of coding parameters involved. We solve Problem 2 (economical contexts) by using the buckets of the surrounding pixels as components of the conditioning class. The bucket values have the desirable properties needed for the error distributions. View full abstract»

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  • Regenerative simulation methods for local area computer networks

    Publication Year: 1985 , Page(s): 194 - 205
    Cited by:  Papers (2)
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1013 KB)  

    Local area computer network simulations are inherently non-Markovian in that the underlying stochastic process cannot be modeled as a Markov chain with countable state space. We restrict attention to local network simulations whose underlying stochastic process can be represented as a generalized semi-Markov process (GSMP). Using “new better than used” distributional assumptions and sample path properties of the GSMP, we provide a “geometric trials” criterion for recurrence in this setting. We also provide conditions which ensure that a GSMP is a regenerative process and that the expected time between regeneration points is finite. Steady-state estimation procedures for ring and bus network simulations follow from these results. View full abstract»

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  • Recent papers by IBM authors

    Publication Year: 1985 , Page(s): 206 - 213
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (736 KB)  

    Reprints of the papers listed here may usually be obtained by writing directly to the authors. The authors' IBM divisions or groups are identified as follows: CHQ is Corporate Headquarters; CPD, Communication Products Division; DSD, Data Systems Division; ESD, Entry Systems Division; FED, Field Engineering Division; FSD. Federal Systems Division; GPD, General Products Division; GTD, General Technology Division; IPD. Information Products Division; ISG, Information Systems Group; IS&CG. Information Systems & Cornmunicaiions Group; IS& TG, Information Systems & Technology Group; NAD, National Accounts Division; NMD, National Marketing Division; RES, Research Division; SPD, System Products Division; SRI, Systems Research Institute: and STD. Systems Technology Division. View full abstract»

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  • Recent IBM patents

    Publication Year: 1985 , Page(s): 214 - 216
    Save to Project icon | PDF file iconPDF (236 KB)  
    Freely Available from IEEE

Aims & Scope

The IBM Journal of Research and Development is a peer-reviewed technical journal, published bimonthly, which features the work of authors in the science, technology and engineering of information systems.

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Editor-in-Chief
Clifford A. Pickover
IBM T. J. Watson Research Center