Hl-2m Lhcd Antenna Development

A 4MW/3.7GHz/3s LHCD system will be developed on HL-2M tokamak. Up to now, half of the system has been constructed, including a 4MW full active multijunction (FAM) concept antenna. The antenna consisted of 6x32 grills. 1-3 power divider in poloidal direction based on TE10-TE30 mode converter is used for 6-row realization. The peak refractive index is designed as n(parallel to 0)=2.25, with high directivity D=0.75 and low reflection coefficient RC<1%. The maximum power density is 41MW/m(2), which is acceptable for HL-2M LHCD system. The whole antenna body is separated to 8 modules, all made of stainless steel. The RF characteristic of the antenna is tested via special designed measurement components. The test result has shown that the reflection coefficient, transmission characteristic and the phase shift of the grills match the design, indicating the antenna is well manufactured.