Analog Receiver and Transmitter Design for the ILC Main LINAC LLRF Control System

Particle accelerators of the next generation, like the International Linear Collider (ILC), will need exceptional beam quality in order to achieve the required luminosity and beam energy dictated by the experiments. Performance of a low-level radio frequency (LLRF) control system plays a major role in preserving beam quality in a particle accelerator. LLRF system regulation specifications are usually given in terms of phase and amplitude stability of the detected fields in a cavity and in the case of the ILC these are not the same for all parts of the machine. For instance, bunch compressor and damping rings have more severe specifications in terms of regulation than the main linear accelerator (LINAC). In the introduction, we present the main design issues for the ILC main LINAC LLRF system and focus on the analog receiver and transmitter design. In the first section a short overview of the main design approaches is given. In the following section we present measurements of the main building blocks in an analog receiver and transmitter and apply measured data on a model. We study interactions between the two modules, when integrated in a closed loop LLRF system. At the end, we present results followed by conclusion.