A   B   C   D   E   F   G   H   I   K   L   M   N   O   P   R   S   T   U   W    

closed-orbit

Paper Title Other Keywords Page
IT07 Digital Signal Processing in Beam Instrumentation: Latest Trends and Typical Applications diagnostics, instrumentation, controls, betatron, feedback 30
 
  • M.E. Angoletta
    CERN, Geneva, Switzerland
  During the last decade digital signal processing has found its way into the beam instrumentation arena, to become an essential part of several beam diagnostic systems. In fact, the recent impressive hardware performance improvement made it possible for functions once exclusively accomplished by analogue methods, to be enhanced by the application of an alternative digital approach. This is true to a point that the conversion to digital processing has become inevitable. Factors that favour crossing the border towards digital implementation are obviously speed as well as precision, signal-to-noise ratio, dynamic range, stability of components and configuration capability, together with the availability of powerful and user-friendly development tools. Improvement in A/D conversion and processing speed has allowed successfully developing digital feedback loops and on-line diagnostics. The ascent of such digital techniques generated a concurrent and parallel interest in digital signal processing algorithms and in the use of the associated digital hardware components. Current trends in beam diagnostics include using Digital Signal Processors (DSPs), Field Programmable Gate Arrays (FPGAs), digital receivers and fast digitizers. The talk reviews latest developments and illustrates selected digital applications, relevant to the beam diagnostic area.  
 
PT08 The LHC Orbit and Trajectory System diagnostics, controls, instrumentation, LHC 187
 
  • E. Calvo-Giraldo, C. Boccard, D. Cocq, L. Jensen, R. Jones, J.J. Savioz
    CERN, Geneva, Switzerland
  • D. Bishop, G. Waters
    TRIUMF, Vancouver, Canada
  This paper describes the definitive acquisition system selected for the measurement of the closed orbit and trajectory in the CERN-LHC and its transfer lines. The system is based on a Wide Band Time Normaliser (WBTN) followed by a 10-bit ADC and a Digital Acquisition Board (DAB), the latter developed by TRIUMF, Canada. The complete chain works at 40 MHz, so allowing the position of each bunch to be measured individually. In order to avoid radiation problems with the electronics in the LHC tunnel, all the digital systems will be kept on the surface and linked to the analogue front-ends via a single mode fibre-optic connection. Slow control via a WorldFIP fieldbus will be used in the tunnel for setting the various operational modes of the system and will also be used to check power supply statuses. As well as describing the hardware involved, some results will be shown from a complete prototype system installed on four pick-ups in the CERN-SPS using the full LHC topology.