The threshold conditions for Trivelpiece–Gould (TG) wave and helicon wave excitation by double-saddle antenna in H-1 are studied. The propagation condition for TG waves is more lenient than that for helicon waves, and the transparency region of helicon waves is smaller than that of TG waves in the plasma density–magnetic field strength plane. At low magnetic fields B < 0.14 T, the threshold density for the excitation of helicon waves gradually increases with B. The temporal evolutions of the wave eigenmodes, radial field structure, power depo...
