Electronic Frequency Tuning Magnetron Using External Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing magnetron technologies face challenges in rapidly and efficiently tuning microwave frequencies due to mechanical movable parts, complex switching elements, and manufacturing difficulties, particularly in maintaining a low atmosphere and avoiding gas release, which limits high-speed frequency changes and increases costs.
Innovation Solution
An electronic frequency tuning magnetron with a coaxial central conductor externally connected to the resonant cavity through a dielectric-covered hole, using a switching element like a PIN diode or varactor diode outside the tube to change the reactance and frequency without mechanical means, allowing for quick and wide-range frequency modulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a mechanical movable part is used to change frequency by adjusting the position of a metal plate in an external resonant cavity, then the reactance of the resonant cavity can be changed to achieve frequency tuning, but the response speed is delayed and high-speed frequency changes cannot be achieved
Solution Approach 1:
The patent replaces the mechanical movable part (metal plate adjustment mechanism) with an electronic switching element (such as a PIN diode or varactor diode) that can change the reactance of the resonant cavity electrically. This substitution eliminates mechanical inertia and friction, enabling high-speed frequency changes of a few hundreds nanoseconds while maintaining the external resonant cavity configuration.
Solution Approach 2:
The patent changes the reactance parameter of the resonant cavity by controlling the conductive condition of the switching element through external signals. By varying the conductivity state of the diode, the reactance is dynamically adjusted, achieving frequency tuning without mechanical movement. This parameter-based control enables rapid frequency switching.
2Productivity
If a switching element is placed within the exhausted tube to change the conductive condition and thereby change the reactance of the resonant cavity, then frequency can be changed electronically, but the manufacturing becomes difficult and costs increase due to the need to maintain low atmosphere and avoid gas release
Solution Approach 1:
The patent extracts the switching element from the exhausted tube interior and places it in the external resonant cavity. This extraction eliminates the need to maintain the low-atmosphere environment within the tube while achieving the same frequency tuning function. The switching element operates externally where normal atmospheric conditions prevail, greatly simplifying manufacturing and reducing costs.
Solution Approach 2:
The patent introduces a coupling mechanism (such as a coupling aperture or electromagnetic coupling structure) that mediates between the external switching element and the resonant cavity. This intermediary allows the external switching element to control the reactance of the resonant cavity without being physically inside the exhausted tube, thereby maintaining the vacuum seal while enabling electronic frequency control.
3Adaptability or versatility
If metal is inserted into the resonant cavity to modify the reactance and increase inductance or capacitance, then the oscillating frequency can be changed, but mechanical means with movable parts are required which delay response and prevent high-speed frequency changes
Solution Approach 1:
The patent replaces the mechanical insertion method (physically moving metal into the resonant cavity) with an electronic switching element that can be activated or deactivated electrically. This substitution maintains the ability to modify reactance and achieve frequency tuning across a desired range, while eliminating mechanical movement to achieve high-speed response times of a few hundreds nanoseconds.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables reliable, low-cost, high-powered microwave frequency tuning with rapid response and reduced manufacturing complexity, avoiding the limitations of mechanical parts and complex switching elements, while maintaining a stable resonant cavity and minimizing interference.
Implementation Method 1
the through-hole is covered by a dielectric portion placed between an external conductor and the central conductor for constituting the coaxial central conductor
Implementation Method 2
providing a switching element outside a tube of a magnetron for enabling to change the conductive condition of the switching element provided in the resonant cavity by an external signal
Implementation Method 3
an oscillating frequency is determined by reactance which is configured by both the straps 4 and the segment cavity
Data Source
AI summary
A highly-reliable electronic frequency tuning magnetron comprises an anode for forming a resonant cavity which is segmented into a plurality of spaces in an inner periphery side of a cylindrical anode shell, a cathode provided at the center of the anode shell along its cylindrical axial direction and an exhausted structure having a coaxial central conductor which is connected to the inside of the cavity of the anode shell and is coupled thereto in a high-frequency manner, wherein the coaxial central conductor is externally led through a wall of the exhausted structure via a through-hole and the through-hole is covered by a dielectric portion placed between an external conductor for constituting the coaxial central conductor and the central conductor, wherein a portion of the led coaxial central conductor is conductively connected to a switching element.