SLAC, Menlo Park, California, USA
SLAC is developing a new X-band Cavity BPM receiver for use in the LCLS-II for use in the LCLSII. The Linac Coherent Light Source II (LCLS-II) will be a free electron laser (FEL) at SLAC producing coherent 0.5-77 Angstroms hard and soft x-rays. To achieve this level of performance precise, stable alignment of the electron beam in the undulator is required. The LCLS-II cavity BPM system will provide single shot resolution better than 50 nm resolution at 200 pC *. The Cavity BPM heterodyne receiver is located in the tunnel close to the cavity BPM. The receiver will processes the TM010 monopole reference cavity signal and a TM110 dipole cavity signal at approximately 11 GHz using a heterodyne technique. The heterodyne receiver will be capable of detecting a multibunch beam with a 50ns fill pattern. A new LAN communication daughter board will allow the receiver to talk to an input-output-controller (IOC) over 100 meters to set gains, control the programmable dielectric resonator oscillator, enable self-test, and monitor the status of the receiver. We will describe the design methodology including noise analysis, distortion analysis.
* Commissioning and Performance of LCLCS Cavity BPMs, Stephen Smith, et. al, Proceedings of PAC 2009, Vancouver, BC, Canada.
