An oscillator circuit for generating signals with a predetermined oscillator frequency is provided. A step count-acquiring section acquires a step count of the user of a mobile terminal. Curved rails are formed at both sides of the central groove on the bottom of the mat member, which has curved portions corresponding to the curvature of the vertebral region of a user. The digital signal is filtered to substantially reduce a power level of the digital signal at frequencies that correspond to channels in the band that have not been determined to be available.