Patent ID: 7701392

Claim:
An antenna system, comprising: an antenna having switchable directivity when receiving an analog television broadcasting signal; a switching section that switches the directivity of the antenna; a measurement section that measures radio wave quality of the analog television broadcasting signal received by the antenna by analyzing the analog television broadcasting signal when the directivity of the antenna is switched by the switching section; a storage section that stores data of radio wave quality in different directions measured by the measurement section for each channel; a control section that controls the switching section to switch the directivity of the antenna to one direction having a highest radio wave quality among the different directions corresponding to a desired channel when the desired channel is designated; and a determining section that determines whether the analog television broadcasting signal is received by the antenna when the directivity of the antenna is switched by the switching section, wherein if the determining section determines that the analog television broadcasting signal is received by the antenna, the measurement section measures the radio wave quality of the analog television broadcasting signal by analyzing the analog television broadcasting signal, and the control section controls the switching section to sequentially switch the directivity of the antenna in descending order of radio wave quality among the different directions corresponding to the desired channel until the determining section determines that the analog television broadcasting signal is received by the antenna.