| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a portable altimeter 10 comprising a pressure sensor 14, a calculation unit 16, a time measuring device 18, and a calibration circuit 32. <P>SOLUTION: In this portable altimeter, the calculation unit 16 determines the altitude value H as a function of pressure P which is measured by the pressure sensor 14, and as a function of reference temperature T<SB>0</SB>, corresponding to a predicted value of the temperature of air mass at the sea level (zero height above sea level). The time measuring device 18 provides date D of a calender, and the calibration circuit 32 selects the reference temperature value T<SB>0</SB>as a function of date D from a series of values T<SB>S</SB>, contained in a database included inside the altimeter 10 and as a function of predetermined climate C. A method of determining the altitude H is also provided. <P>COPYRIGHT: (C)2008,JPO&INPIT |
