Abstract: | Aluminium and copper prototype cavities were designed to study higher order modes(HOM).An automatic field mapping system was developed with LabVIEW to measure the adiofrequency(RF)charac teristics,such as resonant frequency,Q-value,shunt impedance and electromagnetic field distribution of the higher-order modes in a model RF cavity.Two kinds of the bell-shaped cavities were measured using the field mapping system,their frequencies are 1.5 GHz and 800 MHz respectively.The fields' distributions of the monopole modes and dipole modes,as well the R/Q values,were measured. |