Design improvements for mode and polarization converters for 6-GHz gyrotrons
Thesis/Dissertation
·
OSTI ID:5104361
Gyrotrons currently in use typically have circular-waveguide microwave outputs in the TE/sub 01/ or TE/sub 02/ modes which are not efficient for plasma heating. Periodic perturbation type mode converters have been successfully used to convert these outputs to a TE/sub 11/ or HE/sub 11/ mode which have more efficient plasma heating characteristics. Methods are discussed by which the efficiency and power handling capability of those mode converters can be increased while their length is simultaneously reduced. The mode converter's bandwidth is also usually increased. These improvements are accomplished by (1) changing the perturbation period slightly from the beat wavelength between the input and the desired output mode to account for the effect of the presence of unwanted modes, (2) inserting sections of straight waveguide to adjust the relative phases of the important modes so that coupling to unwanted modes is minimized, (3) varying the amplitude of the perturbation from period to period to maximize the converter efficiency, and (4) choosing the profile of the perturbation period to further reduce the coupling to unwanted modes.
- Research Organization:
- Stanford Univ., CA (USA)
- OSTI ID:
- 5104361
- Country of Publication:
- United States
- Language:
- English
Similar Records
Quasi-optical internal mode converters for 110 GHz gyrotrons
Circular waveguide mode converters at 140 GHz
Mode converters used in the Doublet III ech microwave system
Conference
·
Sat Dec 30 23:00:00 EST 1995
·
OSTI ID:170210
Circular waveguide mode converters at 140 GHz
Technical Report
·
Tue Dec 31 23:00:00 EST 1985
·
OSTI ID:5955281
Mode converters used in the Doublet III ech microwave system
Conference
·
Tue Jun 01 00:00:00 EDT 1982
·
OSTI ID:6553549