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Simulations, libespec... some thoughts bino@hep.ucl.ac.uk. WP 4.2 review meeting. Wednesday, 13 September 2006, UCL, bino@hep.ucl.ac.uk. Creating a simulation/analysis library : introducing libespec. Important aims : - high granularity, “little black boxes” as Stewart put it :)
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Simulations, libespec... some thoughts bino@hep.ucl.ac.uk WP 4.2 review meeting Wednesday, 13 September 2006, UCL, bino@hep.ucl.ac.uk
Creating a simulation/analysis library : introducing libespec Important aims : - high granularity, “little black boxes” as Stewart put it :) - plain ANSI C for portability and easy interface with e.g. ROOT, LabVIEW... - highly and accurately documented (Doxygen) - system independent (GNU autotools) - using real physical SI units such as Hz, sec, kg etc instead of e.g. “Inverse samples times Nyquist frequency in GHz divided by Pi to the power 2/3”... or something similar ;))). That said... were are we with this ? Heavy construction ! Code lives in CVS under : http://cvs.hep.ucl.ac.uk/viewcvs/especSoft/?cvsroot=LC+Energy+Spectrometer And has it's web page with latest distribution tar ball + documentation in pdf/html format http://www.hep.ucl.ac.uk/~bino/libespec/ Wednesday, 13 September 2006, UCL, bino@hep.ucl.ac.uk
BPM/Electronics simulation using libespec Describe signals from BPMs as complex waveforms Choose physical sampling frequencies and system of units e.g. : // generate an LO source at 2939 MHz, sample it at 35 GHz to use in code here AddComplexLO( 5.*Volt, 2929*MHz, 1.2, 0., 0., 35*GHz, samples, LO, t ); // generate a BPM waveform, sample it at 35 GHz as well to use in the code AddComplexWaveform( 5.*Volt, 2.856*GHz, 1.5, 200*nsec, 50.*nsec, 0., 35*GHz, samples, RF, t ); // the mixer, having -2dB power conversion and 20 dBm 1dB compression factor MixComplexWaveforms( RF, LO, IF, samples, -2.0, 20. ); // apply a lowpass filter : 10th order butterworth low pass filter... // with cut off frequency of 100 MHz... ButterworthLowPass( IF, samples, 35.*GHz, 100.*MHz, 10 ); // digitise the waveform DigitiseWaveform( IF, samples, t, adc, 119.*MHz, 10.*nsec, 0.5*nsec, 256, 14, -2.5, 2.5, 75.0 ); Wednesday, 13 September 2006, UCL, bino@hep.ucl.ac.uk
BPM/Electronics simulation using libespec Simulate real electronics, e.g. non-linearity and conv. loss Waveform digitisation, with saturation, noise, pedestal etc... Wednesday, 13 September 2006, UCL, bino@hep.ucl.ac.uk
A really tacky flow chart !!! Real BPM Electronics digitisation reconstruction ... GdFidl (cavity par.) Waveform simulation Electronics digitisation simulation LIBESPEC • Also include mover simulation (vibrations, etc....) • Process e.g. Tracked particles from ELEGANT simulations and have a full • simulation of the BPM spectrometer based upon a single C library at all stages • (online LabVIEW, offline analysis, FPGA ?? )... • Maybe base nanoBPM/ESA production codes on same set of core routines... • NEED TO DISCUSS ON THE FURTHER STRUCTURE OF ACTUAL ESPECSIM !!! Wednesday, 13 September 2006, UCL, bino@hep.ucl.ac.uk