GEC-Marconi RDSL

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Goto top of this pageBasics

Employer GEC-Marconi Radar and Defence Systems Ltd., Stanmore
Dates February 1987 - June 1997
Business area Electronic Warfare Systems
Position Engineer, Senior Engineer, Principal Engineer

Goto top of this pageEngineering Tasks

Pulse Measurement Circuits Design / debug / system integration of complex task-specific DSP boards for various RADAR detection equipments
Future Pulse Measurement Techniques Invent and evaluate ideas for the next generation of pulse measurement circuits
Future RADAR Detection Systems Architectures Invent and evaluate ideas for the next generation of RADAR detection equipments
Technical Proposal Support Assist in the design of system architectures for proposal to potential customers
RF-channelised Pulse Detection System Design / debug / integration of the DSP sections of an RF-channelised Pulse Detection System; this was leading-edge work
DSP-channelised Pulse Detection System Initial concept and design work on a DSP-channelised Pulse Detection System; this also was leading-edge work
Other Engineering Work Research / design / debug / integration of various other pieces of electronics as company workload required
Other Minor Activities The normal practice of sharing good ideas and difficult problems around an engineering group, Mentor ECAD utilities and library development, lab. GPIB utility software

Go up this page to 'Engineering Tasks'Pulse Measurement Circuits

Project RADAR Detection/Identification Equipment
Sphere of Work Product design, debug, test, post-design support.

Military system
Responsibilities Design, debug and test of a pulse measurement board - a fast DSP board with some 10MHz analogue inputs; associated DSP algorithm refinement, including building some large, complex PROM look-up tables.

Board test definition and test equipment design

Integration and system test.

Post-design modifications to allow use of the board on other platforms.
Hardware Skills Analogue and Mixed Signal
  • 15MHz video input, threshold detection, A to D conversion.
  • basic use of microwaves to 20GHz for board algorithm definition and during system test

Digital

  • timing critical logic in the board front-end
  • fast, pipelined, algorithm-specific DSP circuits; adders, comparators, multipliers, etc.,
  • standard logic,10k ECL, fast PALs - mostly 22v10,
  • DataIO Abel/AHDL for generating PAL programming data,
  • 68020 microprocessor
DSP Skills Aperiodic pulse measurement, implemented in algorithm-specific hardware (rather over 500MIPs equivalent on a board back in 1984!).
Software Skills Large (>10 000 line) desktop programme suite to generate complex look-up table data and estimate system operational accuracy. Written in Pascal using OOP methods; hosted on VAX-VMX.

Small programmes for general design calculations. Written in Pascal; hosted on VAX-VMX.

Small programme to provide printing and configuration storage for various test equipments via GPIB. Written in BASIC; hosted on HP-300 computers.

Small programme for board test control, including configuration loading for various test equipments via GPIB. Written in BASIC; hosted on HP-300 computers.

Small programme to read results from a Pulse Measurement Board via a general parallel interface in near real-time. Written in Pascal; hosted on HP-300 computers.
Debug/Test Skills System level and board level testing.
  • Analogue and real-time digital oscilloscopes; fast logic circuit probing; accurate observation of glitch/line driving problems
  • Logic analysers for digital circuit debug
  • Microwave synths to 20GHz during system integration
  • Pulse generators for video generation and microwave synth. modulation
  • Digital pattern generators for board stimulus and handshake generation
  • Arbitary waveform generators for video generation
  • GPIB control and direct handshaking from HP-300

Go up this page to 'Engineering Tasks'Future Pulse Measurement Techniques

Project Research into new pulse measurement techniques for RADAR Detection/Identification Equipments.
Sphere of Work Possible future product techniques/theory.
Responsibilities Invent novel pulse measurement ideas (DSP algorithms and hardware implementations).

Evaluate pulse measurement ideas in terms of performance and realisability.
Notes This work grew from ideas that came up while doing the Pulse Measurement Circuits work. It continued spasmodically for the entire period at GMRDSL.

Most evaluation was done on paper, using a combination of accumulated experience of received pulse shapes for evaluating performance, and sketch system architectures and circuit designs for evaluating realisability.

Commercial viability also came into the evaluation.
Hardware Skills Analogue
  • general 10MHz-20MHz bandwidth video circuits
  • some additional RF/microwave theory and techniques - to 20GHz.

Digital

  • fast pipelined design and control techniques,
  • complex arithmetic circuit designs in standard MSI/LSI parts and Xilinx LCAs,
  • Xilinx XACT-XDE hand editor for LCA sketch designs.
DSP Skills Advanced aperiodic pulse measurement; noise processing and inteligent threshold generation. Sketch implementations in algorithm-specific hardware (looking at well over 2GIPs equivalent on a board back in the mid-1980s!).
Software Skills Small programmes for basic algorithm checking. Written in Pascal; hosted on VAX-VMS.
Debug/Test Skills General testing.
  • Analogue and real-time digital oscilloscopes; fast logic circuit probing; accurate observation of glitch/line driving problems
  • Microwave synths to 20GHz during system testing
  • Pulse generators for video generation and microwave synth. modulation

Go up this page to 'Engineering Tasks'Future RADAR Detection Systems Architectures

Project Research into new system architectures for RADAR Detection/Identification Equipment
Sphere of Work Possible future product system architecture/techniques/theory.
Responsibilities Invent novel system architecture and circuit ideas.

Evaluate the ideas in terms of performance and realisability.

Find better ways of using existing technology; keep abreast of new technology.
Notes This work grew from ideas that came up while doing the Future Pulse Measurement Techniques work. It continued spasmodically for the rest of the period at GMRDSL. It relied heavily on the experience gained in that work.

An interesting part of this work was keeping track of the highly complex interactions of the disparate parts of the whole system (involving everything from low noise microwave front-ends through DSP blocks and complex bus structures to general purpose processor board farms.

Commercial factors played a major part in the work through the influence of the Technical Proposal Support work, and also through discussions with some of the marketing people at GMRDSL.
Hardware Skills Many paper designs were completed and discussed, utilising skills listed elsewhere in this CV. To avoid excess repetition only additional skills are listed here.

Analogue

  • wider view of RF/microwave techniques.

Digital

  • investigation of diverse comms and bus standards including ...
    (various proprietary standards)  
    VME Bus (and many extensions) good understanding
    FutureBus good understanding
    SCI good understanding of both parallel and serial versions
    RS232/RS423 good understanding
    RS422 good understanding
    PCI Bus moderate understanding
    PC-AT Bus moderate understanding
    RamBus moderate understanding
    FireWire rough understanding
    USB rough understanding
    FDDI rough understanding
    standard microcontroller serial interfaces rough understanding
  • complete definition of a robust, very compact, high performance backplane bus.
  • At least basic knowledge of many microprocessor devices, including ...

    ARM
    MIPS
    Sparc
    80x86
    680x0.
Software Skills Small programmes for basic algorithm checking. Written in Pascal; hosted on VAX-VMS.

Small programmes for system accuracy estimation. Written in Pascal; hosted on VAX-VMS.

Small programmes to aid evaluation of replacing data sorting hardware with software. Written in C; hosted initially on PC-DOS, then on a vendor's performance estimating system.

Go up this page to 'Engineering Tasks'Technical Proposal Support

Project Provide input into proposals to potential customers for RADAR Detection/Identification Equipment
Sphere of Work Possible future product architecture paper design.

Military systems.
Responsibilities Assist in systems architecture design, and produce outline board circuit designs for feasibility study/costing purposes.

Provide to the proposal work other technical support as needed
Notes This work complemented - helped and was helped by - the Future RADAR Detection Systems Architectures work.

It required the pursuit of technical excellence to be balanced against commercial factors - whether cost, acceptability to internal management, or marketability in a conservative marketplace.
Hardware Skills Paper design exercises using experience from other work.
Software Skills Large (>10 000 line) desktop programme suite to generate complex look-up table data and estimate system operational accuracy for various system and processing configurations. This was an extension of the system-configuration-specifie software developed as part of the Pulse Measurement Circuits task. Written in Pascal using OOP methods; hosted on VAX-VMS.
Support Activities Significant input into mechanical design issues - adding forethought and imagination where the mechanical design staff didn't.

Go up this page to 'Engineering Tasks'RF-channelised Pulse Detection System

Project Research into a novel pulse measurement technique for RADAR Detection/Identification Equipment
Sphere of Work Possible future product technique invention, development and initial laboratory test.
Responsibilities Invent a processing system architecture to make sense of the many outputs from a novel RF front-end; no other such work was known of at the time.

Design, debug, test boards to implement the architecture.

System integration and evaluation.
Notes There were two major but non-obvious parts to this work -
  • generate complex hardware lookup tables to deduce various pulse parameters
  • design board test jigs and write test software

This work involved some very complex circuit boards (believed to be the largest circuit boards ever designed at Stanmore - double sided, >200 ICs, almost double-extended, triple height eurocard size). Significant care was necessary to keep both the design and the documentation understandable and maintainable - standard company procedures were woefully inadequate.
Hardware Skills Analogue and Mixed Signal
  • RF/microwave - interface to the system front end, and provide inputs during testing
  • 15MHz video input, video switching, A to D conversion, BITE D to A conversion

Digital

  • fast pipelined design, complex arithmetic circuits - in LCAs and lookup tables mostly
  • very large board clock transmission - over 500 ICs on several boards operating as a single 5MHz synchronous block,
  • standard logic, fast PALs - 22v10, or in some cases 16l8 for more speed,
  • Lattice ispLSI - for processor interface logic,
  • Xilinx LCA - for complex DSP datapath blocks (included 100% utilisation of xc3090 devices),
  • DataIO Abel/AHDL for generating PAL and ispLSI programming data,
  • Xilinx XACT-XDE for manually generating Xilinx LCA programming data,
  • custom PC interface card on AT-bus - to allow a PC to emulate a proprietry 68020 processor card.
  • 68020 microprocessor
DSP Skills Highly involved, multi-processing, multi-input aperiodic pulse measurement . Implemented in algorithm-specific hardware (aggregate processing >10GIPS for the lab system; a deliverable version could be well over 40GIPS)

Complex data manipulation for optimised pulse look-up table generation. Implemented using MathCad.
Software Skills Large (>10 000 line) programme for processing, hardware control and interface. Included a module that emulated the interface on a GMRDSL standard 68020 processor card. Written in C++ using OOP methods; hosted on PC-DOS/Win3.
Debug/Test Skills System level and board level testing.
  • Analogue and real-time digital oscilloscopes; fast logic circuit probing; accurate observation of glitch/line driving problems
  • Logic analysers for digital circuit debug
  • Microwave synths to 2GHz during system testing
  • Pulse generators for video generation and microwave synth. modulation
  • GPIB control and direct handshaking from HP-300 and PC

Go up this page to 'Engineering Tasks'DSP-channelised Pulse Detection System

Project Research into a novel pulse measurement technique for RADAR Detection/Identification Equipment
Sphere of Work Possible future product initial investigation/feasibility study
Responsibilities Invent a signal processing architecture.

Produce outline board designs to allow estimation of power consumption, cost, etc.
Notes This took the architecture developed in the RF-channelised Pulse Detection System work, and expanded it

The channelisation was implemented digitally rather than in hardware. Consequences for the processing included increased dynamic range and increased channel count.

In addition, the channel processing was made more sophisticated.

It was (at that stage) purely a paper design exercise, and was undertaken at break-neck speed. That said, the design of the highly complex circuits required still required considerable care and discipline.
Hardware Skills Digital
  • fast pipelined design, task-specific DSP design, highly complex multi-processing control
  • standard logic and arithmetic circuits, fast PALs, Lattice ispLSI, Xilinx LCA.
DSP Skills Spectral estimation using windowed fourier transform. Implemented using high performance FFT engine devices.

Highly involved, multi-input, multi-processing, advanced aperiodic pulse measurement; noise processing and inteligent threshold generation. Sketch implementations in algorithm-specific hardware (looking at well over (guestimated) 100GIPs equivalent in a system).

Go up this page to 'Engineering Tasks'Other Engineering Work

Project Various tasks, some of which it is inappropriate to discuss in detail.
Sphere of Work Possible future systems techniques research and associated paper designs to assess realisability.

Product design, debug, test.

Military systems

Some safety-critical hardware.
Responsibilities Board design, simulation, debug, test - mostly of unexciting boards.

Some board test definition and test equipment design

Integration and system test.

This included working at customer sites.
Hardware Skills Analogue and Mixed Signal
  • general low speed circuits

Digital

  • standard logic, various small PALs,
  • Atmel atv2500 - for sequencing and control,
  • Xilinx LCA - for data packet assembly, classification, sorting, time-stamping and similar tasks
  • DataIO Abel/AHDL for generating PAL (incl. atv2500) programming data,
  • Xilinx XACT-XDE for manually generating Xilinx LCA programming data,
  • Mentor ECAD with Xilinx logic synthesis for generating Xilinx LCA programming data.
  • 68020 microprocessor

System Interface

  • various real-world interfaces - mostly to diverse aircraft systems, including discrete signals and synchros.
DSP Skills Correlation/autocorrerlation algorithms.
Debug/Test Skills System level and board level testing.
  • Analogue and real-time digital oscilloscopes; fast logic circuit probing
  • Logic analysers for digital circuit debug
  • Pulse generators for interface circuit test
  • Digital pattern generators for board stimulus and handshake generation
  • GPIB control from HP-300
Support Activities Mechanical ... detailed vibration testing (operability and survivability) of safety-critical hardware.

Go up this page to 'Engineering Tasks'Other Minor Activities

Project
  • the normal practice of sharing good ideas and difficult problems around an engineering group
  • Mentor ECAD utilities and library development
  • improve laboratory test equipment GPIB management software as needed
Sphere of Work Various, from military systems to general laboratory software, from research to library maintenance
Notes There was exposure to many areas of work, including novel techniques research, systems architecture, and circuit design and debug.

The library development activity was a result of being part of one of the first groups at GMRDSL to use ECAD for circuit design. It began as a necessity, and continued after a formal ECAD administration group had been formed.

The laboratory test equipment software was initially written as part of the Pulse Measurement Circuits work; it evolved further as a result of being used to support subsequent work.

Included below are skills that were exercised to a significant degree; passing involvements are not recorded.
Hardware Skills Analogue and Mixed Signal
  • general analogue and interface work,
  • RF/microwave up to 10GHz signals - treated as both frequency-domain (RF) and time domain (video) signals
  • ASIC - mixed signal, full custom GaAs,
  • Saber mixed signal simulation,

Digital

  • standard logic and ECL - including Mot. ECLinPS,
  • ASIC - moderate size digital,
  • VHDL - understand and comment on,
  • PALs - 22v10 mostly, Lattice ispLSI - 1000 series, 3000 series, Xilinx LCA - 3000 series, some 4000 series,
  • DataIO Abel/AHDL - PAL and ispLSI programming data,
  • DataIO Synario - PAL and ispLSI programming data,
  • Xilinx XACT-XDE and synthesis tools - Xilinx LCA programming data.
  • 68020 microprocessor
  • 8051 microcontroller
Software Skills Working with embedded real-time control software, in ADA / 68020 assembler.

Small programme to provide printing and configuration storage for various test equipments via GPIB. Written in BASIC; hosted on HP-300 computers.

Small and medium-size utility programmes for use with the Mentor ECAD software. Written in Pascal; hosted on Apollo-Domain computers.

Other small programmes, generally for test site control/user-interface. Written in Visual BASIC; hosted on PC-Win3 computers.
Debug/Test Skills System level and board level testing.
  • Analogue and real-time digital oscilloscopes; fast logic circuit probing; accurate observation of glitch/line driving problems
  • Sampling oscilloscopes (Tek CSA) to 10GHz for high speed analogue debug; very high speed probing techniques
  • Logic analysers for digital circuit debug
  • Microwave synths to 10GHz during system integration
  • Pulse generators for video generation and microwave synth. modulation
  • Arbitary waveform generators for video generation
  • GPIB control and direct handshaking from PC and HP-300

Goto top of this pageSupport Environment

Desktop Computer Systems
  • PC-DOS/Win3/Win95
  • VAX-VMS
Desktop Software - General
  • Adobe Acrobat
  • MS Office (Word, Excel)
  • Netscape
  • VAX TPU
Lab/Specialist Computer Systems
  • Apollo-Domain/HP-Unix
Lab/Specialist Software
  • Mentor

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Curriculum Vitae > Career ... > GEC-Marconi RDSL / John Dubery / 8 April 2000