Patent ID: 8270922
Filing Date: 2012-09-18
Classification: H03J,H04B

Abstract:
1. A radio wave receiver, comprising: an antenna to receive a radio wave; a tuning unit to switch a frequency characteristic of the antenna in a stepwise fashion; a positive feedback unit to oscillate the antenna and a circuit section of the tuning unit by applying a positive feedback to a signal path including the tuning unit; a switching unit to turn a feedback operation of the positive feedback unit on or off; a receiving process unit to carry out a signal process by extracting a signal of a desired wave among received signals which are received from the antenna, in a state in which the feedback operation of the positive feedback unit is turned off; a search control unit for causing the positive feedback unit to generate an oscillation signal at the circuit section and searching for a setting condition of the tuning unit in which the oscillation signal is extracted in the receiving process unit while switching a setting of the tuning unit, in a state in which the feedback operation of the positive feedback unit is turned on; and a search range deciding unit to selectively decide an adjustable range in which the switching of the setting of the tuning unit is carried out by the search control unit so as to be a specific adjustable range which is a portion of an entire adjustable range of the tuning unit corresponding to a frequency of the desired wave according to the following formula (1): wherein: