This paper is a result of the work done by the authors in the field of movement evaluation at low speed in the atmosphere and low costs of the movement execution. Theoretical and constructive solutions are offered for telemetry of the following features of movement: instant and average speed, movement sense and direction, instant position related to a fixed referential. The presented solution, the Doppler radiotelemetry system with active fixed referential -described in the paper -was

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... y realized and experimentally its utility has been demonstrated. Keywords: Mobile referential, fixed referential, Doppler shift in frequency, Doppler signal extractor. © and s 2¨f2 © signals, by using a frequency synthesizer with two PLL loop, PLL1 and PLL2, and a signal generator with the reference frequency s r¨fr © . In order that the signal s 2¨f2 ¥