Near real-time ORM measurements and SVD matrix generation for 10 Hz global orbit feedback in RHIC

To reduce the effect of trajectory perturbations ({approx}10 Hz) due to vibrations of the final focusing quadrupoles at RHIC, global orbit feedback was successfully prototyped during run-10. After upgraded to a system with 36 BPMs and 12 correctors, 10 Hz feedback was tested successfully in Run-11 and is in operational status for physics program. The test and operation of the system has been performed using transfer functions between the beam position monitors and correctors obtained from the online optics model and a correction algorithm based on singular value decomposition (SVD). One of our goals is to self-calibrate the system using SVD matrices derived from orbit response matrix (ORM) measurements acquired real-time using the new FPGA-based signal processing. Comparisons between measurement matrix and model matrix and the generation of SVD matrix for the feedback operation are presented