WP 4.2 review meeting

1
WP 4.2 review meeting

• Simulations, libespec...
• some thoughts
• bino_at_hep.ucl.ac.uk

Wednesday, 13 September 2006, UCL,
bino_at_hep.ucl.ac.uk
2
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.u
k/viewcvs/especSoft/?cvsrootLCEnergySpectromete
r
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_at_hep.ucl.ac.uk
3
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, 2929MHz, 1.2, 0., 0., 35GHz, samples,
LO, t ) // generate a BPM waveform, sample it
at 35 GHz as well to use in the code
AddComplexWaveform( 5.Volt, 2.856GHz, 1.5,
200nsec, 50.nsec, 0., 35GHz,
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, 0.5nsec, 256,
14, -2.5, 2.5, 75.0 )
Wednesday, 13 September 2006, UCL,
bino_at_hep.ucl.ac.uk
4
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_at_hep.ucl.ac.uk
5
A really tacky flow chart !!!
Real BPM
reconstruction
...
Electronics digitisation
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_at_hep.ucl.ac.uk