Redazione RHC : 19 August 2025 08:48
Chinese engineers have announced the development of a miniature traveling-wave tube (TWT) that could revolutionize the capabilities of modern electronic warfare systems and radar. This special type of vacuum tube amplifies radio frequency signals in the microwave range and has long been considered a key element of radar systems and satellite communications links. The main feature of the TWT is that the electromagnetic wave interacts with the electron beam along the entire length of the spiral, ensuring a wide bandwidth and high efficiency.
For a long time, the large-scale introduction of TWTs was hampered by their size: integrating hundreds and thousands of such modules into phase-shifted antenna arrays was technically difficult. However, Chinese specialists managed to reduce the dimensions of a powerful TWT of the X-Ku series to 20 millimeters in height, or less than half the thickness of Western analogues. According to media reports, the new lamp is comparable in size to a pistol and is capable of amplifying microwave pulses in the 8 to 18 gigahertz range, delivering over 500 watts of power through thin spiral conductors.
Structurally, a traveling wave tube is a cylinder with an electron gun forming the cathode, anode plates, a collector, and a spiral (or resonator array). The incoming radio frequency signal is sent to one end of the spiral, and the amplified signal is taken from the opposite end. To increase the electron beam’s interaction time with the electromagnetic field, a so-called slowing structure is used: the most common are a spiral and a coupled resonator array. These solutions allow the field propagation speed to be “adapted” to the electron velocity, which is critical for effective amplification.
The research was led by Shi Xuechun, a scientist at the Beijing Institute of Vacuum Electronics, part of the China Electronics Technology Group Corporation. In June, the research team published their findings in the peer-reviewed journal Vacuum Electronics. The paper highlighted significant advances in miniaturized TWTs in China, with increased bandwidth, power, and efficiency.
In laboratory tests, the new TWT demonstrated dimensions of 185 × 30 × 20 mm with an output power of over 549 watts, a gain of 26 dB, and a dynamic electron beam transmission efficiency of over 97% across the entire beam. These parameters ensure a significant increase in range and detection accuracy in air and missile defense systems. At the same time, the suppression efficiency and range of multi-beam electronic warfare systems are significantly increased.
The authors emphasize that in phased antenna arrays, the number of radiating elements ranges from hundreds to thousands, and the size of the TWT directly influences the system’s critical parameters, from the side lobes of the radiation pattern to the total weight and the possibility of installation on different platforms. Miniaturization and increased efficiency allow these modules to be integrated into modern, next-generation multifunctional complexes, including satellite communications systems and long-range radars.
Therefore, the development of Chinese engineers not only demonstrates the country’s technological independence in the field of vacuum electronics, but also paves the way for the creation of more powerful and compact electronic warfare systems, capable of providing a strategic advantage in a military conflict.
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