Portable terminal for measuring reference tilt and method of measuring reference tilt using the same

A method of measuring a reference tilt of a portable terminal including a controller, comprising:

• dividing, by the controller, a time period into separate time sections and measuring an acceleration in each of the time sections;
• calculating, by the controller, a standard deviation of accelerations in each of the separate time sections by using the measured accelerations;
• determining, by the controller, one time section in which the calculated standard deviation continuously falls below a threshold value over a preset number of repetitions;
• and
• calculating, by the controller, a tilt from an average of the acceleration values in the determined one time section, and setting the calculated tilt as the reference tilt of the portable terminal.

A method of measuring a reference tilt of a portable terminal including a controller, comprising:

• dividing, by the controller, a time period into separate time sections and measuring an acceleration value in each of the time sections;
• calculating, by the controller, a standard deviation of accelerations in each of the separate time sections by using the measured accelerations;
• determining, by the controller, one time section in which the calculated standard deviation continuously falls below a threshold value over a preset number of repetitions;
• and
• calculating, by the controller, a tilt from a sum of weight acceleration values in the determined one time section, and setting the calculated tilt as the reference tilt of the portable terminal.

A method of measuring a reference tilt of a portable terminal including a movement sensor and a controller, comprising:

• dividing, by the controller, a preset time into separate time sections;
• delaying, by the controller, a time period after starting measurement of the reference tilt;
• measuring, by the movement sensor, a tilt after the delayed time, and setting, by the controller, the measured tilt as the reference tilt of the portable terminal,
• wherein measuring the tilt includes
• measuring an acceleration value in each of the separate time sections by using a movement sensor;
• calculating a standard deviation of accelerations in each of the separate time sections, and determining one time section in which movement is minimal based on the standard deviation;
• and
• calculating the tilt of the portable terminal from an average of the acceleration values in the determined one time section.