Single Cavity Amplifier for the International Linear Collider

The International Linear Collider (ILC) will be the largest and most expensive accelerator built to date. Its radio frequency (RF) subsystems ¿ which encompass all of the equipment from external grid power to the delivery of RF power to each of the 20,000 accelerating cavities ¿ are currently estimated to cost ~$1.2B, one of the largest cost items in the ILC design. The baseline ILC approach requires 600 large power supplies and modulators to drive a multiple beam klystron (MBK) operating at 10 MW peak, and then RF power is distributed through a complex network of waveguide components, to power multiple cavities in a parallel topology. This project will design and assess a single cavity amplifier (SCA) that will drive each accelerating cavity in the ILC. In Phase I, the latest RF specifications for the ILC were carefully reviewed to establish the requirements for the SCA transmitter. Numerous microwave amplifier tubes were surveyed to select the best candidate for prototype transmitter testing in Phase II. High voltage topologies suitable for driving the selected tube were reviewed. It was determined that a 1.3 GHz Inductive-Output Tube (IOT) could be combined with a proven solid-state switch cathode pulsing circuit to deliver a compact, high performance transmitter. A preliminary design for the transmitter was completed. In Phase II, the basic design created in Phase I will be carefully detailed for construction. Manufacturing costs for the first article as well as for 20,000 units will be estimated. The prototype transmitter will then be constructed and tested with the IOT. Commercial Applications and Other Benefits as described by the awardee: The simplicity of the SCA, combined with manufacturing learning curves from the production of 20,000 units, should offer significant (30 - 70%) overall cost reductions to ILC RF systems. High RF power could be made available at low cost for any large RF system, including those used for other accelerator designs, food processing, wastewater treatment, semiconductor manufacturing, and military systems such as radars and directed energy systems.