Method for measuring coordinate position and portable electronic device using the same

A portable electronic device, comprising:

• a range finding module for directly detecting a distance between the portable electronic device and a target to generate a measurement signal corresponding to the distance;
• a position identifying module for sensing a relative position of the target to generate an azimuth angle corresponding to the relative position;
• an inertia sensing module for detecting movement of the portable electronic device to generate an inertial signal corresponding to the movement;
• a positioning unit for obtaining a positioning information;
• and
• a processing unit coupled to the range finding module, the position identifying module, the inertia sensing module and the positioning unit, and adapted to not only receive and convert the measurement signal into a distance data but also receive and convert the inertial signal into a tilt angle, calculate a coordinate difference information with the tilt angle, the distance data and the azimuth angle, and calculate a coordinate position of the target with the positioning information and the coordinate difference information;
• wherein the positioning information comprises a first longitude and a first latitude, whereas the coordinate difference information comprises a longitude difference and a latitude difference, and the processing unit calculates the coordinate difference information with equations below,
• Am=π(0−Ar)/180;
• Di=R×cos(Am);
• Δlng=Di×sin(Az)/Ce×cos(red(Lat-o));
• and
• Δlat=Di×cos(Az)/Ce;
• where π is the ratio of the circumference of a circle to its diameter, Ar denotes the tilt angle, R denotes the distance data, Az denotes the azimuth angle, Ce denotes the length of an arc of 1 degree on the Earth's surface, Lat-o denotes the first latitude, Δlng denotes the longitude difference, and Δlat denotes the latitude difference.

A method for measuring a coordinate position, comprising the steps of:

• directly detecting a distance between a portable electronic device and a target to generate a measurement signal corresponding to the distance;
• sensing a relative position of the target to generate an azimuth angle corresponding to the relative position;
• detecting movement of the portable electronic device to generate an inertial signal corresponding to the movement;
• obtaining a positioning information of the portable electronic device;
• converting the measurement signal into a distance data;
• converting the inertial signal into a tilt angle;
• calculating an angle of the target between the distance data and a ground based on the tilt angle;
• calculating a planar distance based on the distance data and the angle;
• calculating a coordinate difference information with the tilt angle, the distance data the planar distance and the azimuth angle;
• and
• calculating a coordinate position of the target with the positioning information and the coordinate difference information.