Patent ID: 7681218

Claim:
A digital television broadcast signal receiver connected to a multi-directional antenna having a plurality of signal receiving directions in compliance with a predetermined technical standard, receiving a digital television broadcast signal by making only one signal receiving direction among a plurality of the signal receiving directions effective, comprising: a tuner for receiving a digital television broadcast signal through the multi-directional antenna; and a controller for switching an effective signal receiving direction of the multi-directional antenna; wherein when a multi-directional antenna is connected to the tuner, the controller measures a term suitable for switching or changing an effective signal receiving direction of the multi-directional antenna, when a user chooses a channel, the controller outputs control signals at an interval corresponding to the measured term so as to switch the effective signal receiving direction of the multi-directional antenna to an optimum signal receiving direction of the channel, and the controller performs following operations for measuring the term suitable for switching or changing the effective signal receiving direction of the multi-directional antenna: selecting two signal receiving directions among a plurality of signal receiving directions of the multi-directional antenna showing sensitivities of television broadcast signals of a channel larger than a predetermined threshold value; switching or changing the effective signal receiving direction of the multi-directional antenna between said two signal receiving directions with shortening the interval for switching or changing the effective signal receiving direction of the multi-directional antenna; measuring sensitivities of the television broadcast signals in said two directions whenever the effective signal receiving direction of the multi-directional antenna is switched or changed between said two signal receiving directions; comparing a measured data of sensitivity with another previously measured data in each of said two signal receiving directions and judging whether compared two measured data of sensitivities substantially coincide with each other or not; and deciding a value of proximate interval as the term suitable for switching or changing the effective signal receiving direction of the multi-directional antenna, when it is judged that said compared two measured data of sensitivities do not coincide with each other.