PURPOSE: A repeater is provided to reduce the amount of computation and the use of resources. CONSTITUTION: A second low noise amplifier(220) amplifies a backward signal which is filtered in a second duplexer. A third mixer(230) mixes the output signal of a second local oscillator and the output signal of a second low noise amplifier. A third filter(240) filters only the intermediate frequency of a third mixer output signal. A fourth filter(250) filters the output signal of a digital FA transforming unit. A fourth mixer(260) mixes the output signal of the fourth filter and the output signal of the first local oscillator.
