RF Phase Control in Pulsed Magnetrons

Theoretical investigation of frequency characteristics of free oscillation and injection-locked magnetrons

“…As it is very difficult to give analytical expressions of electronic admittance and solutions of magnetron self-consistent field equations, many approximation methods and experiments are often adopted to study magnetron. [11][12][13][14][15][16][17][18][19][20] Slater gave approximate electron admittance expressions, which are widely used in latter investigations. [11,12] Welch proposed the expression of a frequent pushing parameter on the voltage by studying the formation of electronic spokes, so the frequency pushing parameter can be quantified.…”

“…[13] For ILM, David presented the expressions of RF voltage and frequency by using an equivalent circuit method, which is widely adopted and developed. [14,15] Woo obtained the time-domain amplitude and phase differential equations of high power ILM power, and performed a dual magnetron mutual-injectionlocking experiment. [16] Chen gave the steady-state expressions of RF voltage and frequency of ILM.…”

“…But in practical applications, the output power of the magnetron is usually adjusted by the voltage or magnetic field, and the oscillation frequency also changes, which has an important impact on both FOM and ILM. However, the present equivalent circuit theory [14,15,17] has not been combined with the frequency pushing theory. [13] So the frequency characteristic of the magnetron with frequency pushing cannot be theoretically calculated with its anode voltage and magnetic field.…”

Analysis of the injection-locked magnetron with a mismatched circulator

“…[7,8] Injection-locking has been studied theoretically and experimentally for a long time. [9][10][11][12][13][14][15][16][17][18][19][20][21] In recent years, the frequency and phase performance of an injection-locked magnetron have been studied in depth. [11,[22][23][24] Adler's condition based on a small injection ratio is widely accepted and adopted by many papers.…”

Observations of Phase Locking in a Single-Cavity Gyrotron Oscillator

“…T HE SYNCHRONIZATION, or locking, of nonlinear l oscillators was reported as early as the 17th century when Huygens observed the phenomenon in clocks placed on a common wall [1]. More recently, it has been reported in microwave tubes, particularly in klystrons and magnetrons [2], [3]. Phase locking, i.e., the locking of the phase, and hence the frequency, of one oscillator with another, is useful whenever mutual coherence is required.…”