Pulse Modulation for Radiation TherapyLeave a Comment
Stangenes Industries is a premier manufacturer of transformers and other electromagnetic components fundamental to the function of life-saving medical systems. For decades, Stangenes Industries has supplied the medical sector with electromagnets, pulse modulator systems, and pulse transformers for use in medical radiation therapy and imaging equipment.
What is a Pulse Modulator?
A pulse modulator generates shaped analog signals through a series of pulses rather than using a continuous signal (DC). This method generates the high peak powers necessary for various RF-generating devices while drawing a relatively low average power. By carefully controlling and arranging components such as switches and diodes, pulse rise-times and widths as short as 10s of nanoseconds and repetition rates as high as 10s of kilohertz can be realized.
Pulse modulators are used as the first stage of power modulation to provide useful beams. At Stangenes Industries, the systems are custom designed according to the application which include:
- Klystron Tubes
- Magnetron Tubes
- Electron Gun Tubes
Additionally, the following testing is employed at our facility:
- Magnetic Core Testing. Pulse power technology has evolved over time, yet Stangenes Industries has remained the industry-leader in pulse transformer technology for over four decades. The heart of the pulse transformer is the magnetic-material that couples the magnetic-flux from the primary to the secondary. This material must meet rigorous testing criteria before being qualified for use in our systems.
- Dielectric Testing. Dielectric tests help to evaluate the efficacy of the insulating barrier materials used in electronic components. These materials protect human users from dangerous shocks and keep currents from travelling between paths within the device. High-power pulse modulation is used to apply pulsing electric fields to the barrier to see how it reacts.
- Transformer Testing. Pulse transformers facilitate the shaping of electrical pulses for an expansive range of applications. Smaller transformers see use in telecommunications circuits, while large transformers are used extensively in power distribution.
Radiation therapy is a primary form of cancer treatment that bombards cancer cells with high-energy waves or particles. Unlike other types of cancer therapies, this type of treatment targets very specific areas where cancer is present to avoid exposing healthy parts of the body to harmful chemicals or surgeries.
At Stangenes, we design and manufacture high-voltage pulse modulators used in radiation therapy equipment. Our pulse modulators are widely customizable, with features including:
- Pulse from several kV up to over 200kV
- Pulse widths ranging from 200ns up to 5ms
- Repetition rates up to several kilohertz
- Peak RF powers up to 20MW
- Average power ratings up to 150kW
- System parallelization for higher peak and average powers
- Competitive pricing
What is a Klystron and How Does it Work?
Radio frequencies can be amplified using a linear-beam vacuum tube known as a klystron. Klystrons were initially designed to help airplanes land in low-visibility conditions, but now have much broader use cases in communications, radar, satellites, and oncology.
Klystrons are radio-frequency (RF) devices that typically operate in a relatively narrow bandwidth range with very high gain. Converse to their narrow bandwidth, these tubes can be manufactured to be highly effective across an extremely broad range of frequencies, ranging from lower-end UHF and surpassing W-band microwave frequencies.
At Stangenes, our product line includes Valhalla Klystron pulse modulators for radiation therapy. This klystron modulator uses solid-state IGBT switches based on a Marx generator topology with built-in droop compensation. The system is water cooled and mounts on an oil-filled pulse transformer tank. This modulator has a small footprint that allows it to fit into rotating gantries and incorporates features that facilitate easier maintenance and troubleshooting. The components are modular so the systems can be ganged to increase the peak and average powers.
About Stangenes Industries
Stangenes Industries designs and manufactures standard and custom pulse modulators used in applications across the medical, military, and industrial sectors. We can provide individual components or full turnkey systems based on your needs. To see how our pulse modulators can support your equipment, please contact us today.