A) In measuring distance by new rangefinders the following methods are used: 1) Phase comparison method 2) Pulse method (measuring travel time of a pulse until it returns) 3) Interferometry method These methods all depend on the fact that the speed of travel of electromagnetic waves is in the order of the speed of light, and this speed must be precisely known. In electronic rangefinders, the first two methods are used more frequently. The third method is used to measure very small distances.
Shamsi,H. (1992). Role of Electromagnetic Waves and Electronics in Surveying and Geodesy - Part IV. Scientific- Research Quarterly of Geographical Data (SEPEHR), 1(4), 52-55.
MLA
Shamsi,H. . "Role of Electromagnetic Waves and Electronics in Surveying and Geodesy - Part IV", Scientific- Research Quarterly of Geographical Data (SEPEHR), 1, 4, 1992, 52-55.
HARVARD
Shamsi H. (1992). 'Role of Electromagnetic Waves and Electronics in Surveying and Geodesy - Part IV', Scientific- Research Quarterly of Geographical Data (SEPEHR), 1(4), pp. 52-55.
CHICAGO
H. Shamsi, "Role of Electromagnetic Waves and Electronics in Surveying and Geodesy - Part IV," Scientific- Research Quarterly of Geographical Data (SEPEHR), 1 4 (1992): 52-55,
VANCOUVER
Shamsi H. Role of Electromagnetic Waves and Electronics in Surveying and Geodesy - Part IV. SEPEHR, 1992; 1(4): 52-55.
