Abstract: According to the theoretical analysis and magnetic field simulation results, an inductively coupled plasma generator for black barrier communication experiment is designed and fabricated. The device can produce a plasma thin layer with the typical characteristics of black barrier plasma sheath with a hemispherical shape, thickness less than 5 cm and plasma density of 1×10¹⁸ m⁻³. Using the method of plasma emission spectrum diagnosis, the electron excitation temperature and electron number density of the plasma produced by the plasma generator are studied, the influence law of coil power on the plasma characteristics is analyzed, and the mechanism is explored, which has a certain reference for the further optimization of the plasma generator and even the radiation control system of electrically small antenna.