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HIGH POWER RF GENERATION & TRANSMISSION

Download the latest version of the Beam Optics Analyzer (BOA) program

About Us

CCR is a leader in development of advanced, innovative technologies for high power RF generation & transmission.

Research Areas

Research is in progress to develop high current multiple beam electron guns without beam compression. This is practical using Controlled Porosity Reservoir (CPR) cathodes, which can provide longlife operation with emission current densities exceeding 30 A/cm2. This is an order of magnitude higher than typically available from dispenser cathodes, allowing confined flow electron beams using flat magnetic fields in the gun.

Since 1999, CCR is the only commercial source of RF loads capable of dissipating more than 1 MW CW of RF power from high frequency gyrotrons. CCR is reducing the cost and improving performance using Additive Manufacturing, commonly referred to as 3D printing. CCR is teamed with N.C. State University and SD3D Inc., to 3D print copper and high strength plastics capable of high pressure and high thermal loads. The current effort is developing loads capable of dissipating up to 2 MW CW.

In 2003, CCR released the first, commercial, 3D, finite element, charged particle code capable of adaptive meshing and integral optimization. Countless upgrades and enhancements now make it one of the most advanced analytical tools of its kind. Beam Optics Analyzer (BOA) supports thermal and stress analysis and multiple generations of secondary electron emission. It’s used in the microwave tube and x-ray source industry to design the next generation of medical, defense, industrial, and scientific electron beam devices. CCR is developing techniques to dynamically refine localized meshes around beam bunches propagating in high energy accelerators.

The next generation of high energy linear accelerators, including the International Linear Collider and the Compact Linear Collider, will require RF sources producing 10 MW or more of RF power in millisecond pulses. The current RF source is the multiple beam klystron, which uses eight or more separate beams to generate sufficient beam power. These sources cost approximately $850K each. The annular beam klystron, if successfully developed, would provide the same operational performance at a cost less than $300K. CCR is continuing development of annular beam klystrons and is investigating an improved electron gun to increase performance.

RF power from gyrotrons is critical for heating fusion plasmas in fusion tokamaks in the search for an unlimited supply of electrical power. Gyrotrons produce one megawatt or more of RF power at frequencies exceeding 100 GHz. RF power at these frequencies and power levels require special transmission lines to reduce loss, and the devices that couple the gyrotron power into the waveguide cost $500K or more. CCR is developing technology to couple the power into the transmission line inside the gyrotron, eliminating the $500K coupler and reducing lost RF power. A prototype gyrotron is currently under construction.

Corrosion is a serious issue in copper cooling systems, particularly when high purity coolant is not available. This a serious issue for marine systems subject to saltwater contamination. With U.S. Navy funding, CCR and N.C. State University developed a system that applies a nano-scale ceramic coating to cooling surfaces to separate the copper from the coolant without impacting heat transfer. A system using Atomic Layer Deposition demonstrated that coolant system lifetimes could be increased by more than 300%. The Navy is currently qualifying the system for critical defense systems.

Magnetrons are perhaps the lowest cost, most efficient source of RF power. These devices, however, are oscillators, so there is no control of the phase, frequency, and amplitude. This prevents use for many applications, including accelerators, radar, and communications systems. CCR is working with SLAC National Accelerator Laboratory to address this issue. In 2019, CCR, in collaboration with Fermilab, successfully tested a 10 kW, 1.3 GHz magnetron system for driving superconducting accelerators. The current program is developing a simpler and more compact system using varactor diodes.

Klystrons are the RF source of choice for many systems, including radar, communications, and accelerators. The klystron is a well established RF source but lacks the efficiency required for many applications. Typical efficiencies range from 55 – 65%. CCR is building a 100 kW CW, 1.3 GHz klystron designed to operate at 80% efficiency. The RF circuit uses the core oscillation method (COM) to more effectively bunch the electron beam for RF power extraction. A prototype klystron is under construction.

Multipactor emission is a serious problem for vacuum windows transmitting MW levels of RF power. Multipactor results when high RF fields cause electron emission avalanche on the material surface. This is mitigated by a 10-15 Angstrom metal alloy coating to reduce secondary electron emission and dissipate electric charge. This coating is typically applied using hot wire sputtering, which works well for small structures, but is insufficient for larger ones. CCR is teamed with VaporPulse, Inc. and Ultramet to develop coating processes using Atomic Layer Deposition and/or Chemical Vapor Deposition. These new process will improve performance and treat structures up to 24 inches or more.

Inductive output tubes (IOTs) are highly efficient sources of RF power from a few hundred MHz up to 1.2 GHz. Efficiencies exceeding 80% are easily achieved, making them desirable for many applications where cost is important. Single beam IOTs, however, are limited to power level typically less than 30 kW. A number of important applications, such as waste treatment and water purification, required 200 kW or more of continuous power. CCR is developing a 700 MHz multiple beam IOT designed to produce 200 kW CW with an efficiency exceeding 80%. A prototype is scheduled for testing in spring 2022.

OUR SERVICES

CCR specializes in designing customized RF and electron beam sources and high power RF components for advanced applications and research.

Hardware Design

Software Development

Thermomechanical Analysis

Electromagnetic Analysis

CAD & Design Services

Dynamic Beam-RF PIC

Get in Touch

CCR’s corporate office is located in San Mateo, CA, with offices in Montpelier, VT, Florence, OR, Mountain View, CA. Inquiries can be sent to RLIves@calcreek.com or by calling (650) 312-9575.

George Collins

George Collins is the Operations Manager, responsible for part procurement, fabrication, assembly, tests, and laboratory operations. He is highly skilled in SolidWorks and approves all mechanical designs in the company. He’s the primary interface with suppliers and vendors and ensures timely delivery and high quality of procured and machined products. He is responsible for high voltage and electron beam processing, including bakeout, hi-potting, and cathode activation. He is highly skilled in precision assembly involving complex interfaces and tight tolerance bonds. He is a major contributor to the mechanical design of all CCR products.

David Marsden

David Marsden is the company’s mechanical designer, responsible for transitioning advanced electron beam and electromagnetic devices from computational models to fabricated devices. He is highly skilled in 3D design and analysis using SolidWorks. Prior to joining CCR in 2001, Mr. Marsden worked as a Senior Mechanical Designer/Department Supervisor at Communications & Power Industries (Palo Alto, CA) and as a Senior Mechanical Designer/CAD Operator at Varian Associates, Inc. (Palo Alto, CA). Since joining CCR, he’s designed gyrotrons, multiple, sheet, and single beam klystrons, traveling wave tubes, multiple beam inductive output tubes, multiple beam power grid tubes, electron guns from a few kV to more than 250 kV, RF loads up to 2 MW, and many RF windows and waveguide components. He is highly skilled in ceramic bonding techniques and designs braze, electron beam, laser beam, tungsten arc, and diffusion bonded joints. Essentially all CCR products are high vacuum devices.

Thuc Bui

Thuc Bui (M’03) received the M.S. from the University of California at Berkeley and Engineer degree in Applied Mechanics from Stanford University. He has performed extensive research in finite element methods and developed and implemented three-dimensional, linear, tetrahedral and hexahedral elements to solve problems in elasticity and compressible fluids and supersonic flows. He is currently using object-oriented programming techniques and finite element methods to solve charged particle beams problems. Mr. Bui is also an experienced user of the finite element codes Marc, Ansys, Ansoft’s Maxwell 2D, Ansoft’s High Frequency Structure Simulator (HFSS), and the finite difference codes Poisson, Superfish, and xgun. He designed several products, including the inductive output tubes (IOTs) electron guns, input and output cavities, and state-of-the-art collectors dissipating 3.5 kW/in2 power densities. Mr. Bui is the principle author of Beam Optics Analyzer and developed the particle pusher, emission algorithms, electric and nonlinear magnetic field solvers and the integration of the mesh generator. He also implemented emission of thermal electrons, temperature limited emission algorithms, self magnetic field calculations, magnetic-to-electric mesh interpolation, variable time stepping algorithms, space charge deposition routines, non-uniform cathode emission, space charge neutralization, and analysis of injected beams.

Thomas Habermann, PH.D.

Quality Assurance

Dr. Habermann received a Ph.D. (Dr. rer. nat.) in Physics from the University of Wuppertal (Germany) in 1999, where he conducted research in field emission. He investigated carbon nanotubes, CVD diamond thin films, diamond-coated silicon microstructures for cold cathode applications, as well as researched the basic mechanisms of ‘parasitic’ field emission impacting superconducting RF cavities used in particle accelerators. From 2000 to 2019 he worked at Communications and Power Industries in Palo Alto, CA, on the development and manufacturing of klystrons. Dr. Habermann managed multiple programs to develop, produce and deliver prototypes or initial production runs of new vacuum electron devices. He contributed to numerous programs within the company and provided engineering support in production. In 2019 Dr. Habermann joined Calabazas Creek Research where he is supporting various R&D programs. He is also responsible for the company’s Quality Assurance.

Lawrence Ives, PH.D.

President & Founder

Lawrence Ives received the Ph.D. degree in Plasma Physics in 1984 and joined Varian Associates, Inc. as a gyrotron engineer. In 1986 he became manager of the High Power Klystron Department, which was responsible for klystron development and production from UHF through C-Band. Dr. Ives founded Calabazas Creek Research, Inc. in 1994 and led development of high power RF loads, multiple beam and sheet beam klystrons, backward wave oscillators, gyrotrons, TWTs, inductive output tubes, controlled porosity reservoir cathodes, advanced electron guns, high power RF windows, reservoir photocathodes, and advanced coatings for emission suppression and corrosion mitigation. He is currently developing multiple beam grid tubes, advanced multipactor coating processes, and gyrotron couplers, as well as integrating 3D printing into high power RF products.

Michael Read, PH.D.

Chief Scientist

Dr. Michael Read – Dr. Read received his Ph.D. in 1976 from Cornell University in Electrical Engineering and Plasma Physics. He worked at the Naval Research Laboratory (NRL) and from 1983 to 1986 was head of the Gyrotron Oscillators and Plasma Interactions Section of Plasma Physics Division. In October 1986, he joined Physical Sciences Inc., where he became Manager of the Electromagnetic Technology Area. Dr. Read joined Calabazas Creek Research in 1999, where he is Chief Scientist and responsible for electron gun, magnetics, and RF circuit design. He is currently leading development of a multiple beam electron gun for a Ka-Band TWT, a 100 kW CW L-Band ultra-high efficiency klystron, and a high power phase-locked magnetron.