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TY - CONF AU - Brajnik, G. AU - Bassanese, S. AU - Cautero, G. AU - Cleva, S. AU - De Monte, R. ED - Schaa, Volker RW TI - Integration of a Pilot-Tone Based BPM System Within the Global Orbit Feedback Environment of Elettra J2 - Proc. of IBIC2018, Shanghai, China, 09-13 September 2018 CY - Shanghai, China T2 - International Beam Instrumentation Conference T3 - 7 LA - english AB - In this contribution, we describe the advantages of the pilot tone compensation technique that we implemented in a new BPM prototype for Elettra 2.0. Injecting a fixed reference tone upstream of cables allows for a continuous calibration of the system, compensating the different behaviour of every channel due to thermal drifts, variations of cable properties, mismatches and tolerances of components. The system ran successfully as a drop-in substitute for a Libera Electron not only during various machine shifts, but also during a user dedicated beamtime shift for more than 10 hours, behaving in a transparent way for all the control systems and users. The equivalent RMS noise (at 10 kHz data rate) for the pilot tone position was less than 200 nm on a 19 mm vacuum chamber radius, with a long-term stability better than 1 um in a 12-hour window. Two main steps led to this important result: firstly, the development of a novel RF front end that adds the pilot tone to the signals originated by the beam, secondly, the realisation of an FPGA-based double digital receiver that demodulates both beam and pilot amplitudes, calculating the compensated X and Y positions. PB - JACoW Publishing CP - Geneva, Switzerland SP - 190 EP - 195 KW - FPGA KW - controls KW - electron KW - feedback KW - Ethernet DA - 2019/01 PY - 2019 SN - 978-3-95450-201-1 DO - DOI: 10.18429/JACoW-IBIC2018-TUOC01 UR - http://jacow.org/ibic2018/papers/tuoc01.pdf ER -