Abstract: A radio receiver apparatus calculates all frequencies to be estimated as spurious frequencies in the reception frequency band by performing addition and subtraction operations on frequencies of repeated combinations formed from frequencies of a plurality of intensive electric field station, and controls the spurious frequency not to be preset to the radio receiver apparatus even though signal intensity of a received signal having the spurious frequency exceeds a predetermined threshold.

Abstract: A base station performs communication of an orthogonal frequency division multiplexing (OFDM) scheme with a mobile station by using any one of equal to or greater than two frequency bands. The base station includes means that transmits a synchronization channel and a control channel using a band that includes a center frequency fA on a raster of a first band (20 MHz) and that has a bandwidth equal to or greater than that of a second band (5 MHz of the end). The control channel includes center frequency information for specifying a center frequency fA? of the second band. Since the mobile station moves to a desired band after obtaining center frequency information using a band including the center frequency on a raster, the mobile station can connect to the desired band without searching frequencies that are not on the raster.

Abstract: An automatic tuning apparatus for a filter includes a mode wherein a switching part is controlled so that a reference signal is inputted to the filter, a plural number of control signals are successively input to a control terminal of the filter, a tentative value of the control signal is determined based on respective amplitudes detected by an amplitude detection part as a “coarse tuning step”, a plural number of control signals are successively input in the vicinity of the tentatively determined value to a control terminal, and the value of the control signal is determined to be used in a mode as a “fine tuning step” based on respective phase differences detected by a phase comparator part”.