Stuff that Alex want me to say during phoneconference
+++++++++++++++++++++++++++++++++++++++++++++++++++++

- go through plots :
  https://www.hep.ucl.ac.uk/elog/Alexey's+logBook/29


  o Plots of simulation of front end filter, mixer and filter behind the
    mixer
  o Alex took parameters from his electromangetic simulation of the
    cavities, -> amplitude of dipole mode
              -> ratio of dipole/monopole for certain offset 
              -> some noise from the BPM
              -> feeding 1 nC of charge into the cavity
    --> from there he constructs a basic response of the cavity with
    monopole and dipole components, this serves as input. The vertical 
    scale on the final output waveforms is in Volts !
  o not that not all losses are taken in to account, the filters and
    mixers are assumed linear, with no noise in the LO.

  o Attachement 2 shows the processed waveform through the filter -
    mixer - filter system at 100nm offset with no noise

  o Attachement 3 adds some noise to that, and it shows up with
    basically no difference at 100nm in the waveform.

  o Attachement 4 shows the dipole at 10 nm offset, without noise,
    Attachement 5 adds the noise. In this case the signal are
    indistinguishable at 10nm, so alex had to go to 20 nm, so this was
    more or less what he thinks will be a first very rough estimate of
    the resolution for these BPMs.

  o Attachement 6 shows the noise level and its power spectrum

  o Attachement 7 shows an kick effect of the filters from the
    monopole component. With some playing around with filter
    bandwidths alex managed to get the amplitude of this transient 
    into the noise level if we take the first filter to be 
    broadband (300MHz). This is why a single sideband filter becomes 
    important as we are not suppressing the image frequencies at the
    front end filter (see electronics scheme). 
  


- Alex plans to improve this simulation by L
  o takin into account the full vector (phase) of the waveforms, currently
    only taking amplitude
  o will talk about it next week
  o suggestions for improvement are welcome