MEASUREMENT OF DOPPLER SHIFT A SEPARATE MODE WITH USE OF THE DOUBLE CHIRP SIGNAL 
 
A.A. Kolchev Mari State Technical University 
V.V. Shumaev Mari State  University 
 
The method of the simultaneous measurement of the frequency dependencies of 
Doppler shift and group delay time of separate ionosphere modes by means of the 
chirp signals is presented in this work. It is offered transmit simultaneously 
two signals with equal parameter: initial frequency and phase, velocity of the 
change the frequency. The Difference consists at initial time of the transmit: 
the first signal displaced for the second signal for time T. 
The processing of a received chirp signal in the receiver by the compression 
method in the frequency range consists in its multiplication by a heterodyne 
signal, complex-conjugated to the transmitted signals, and analysis of the 
resulted difference-mode signal spectrum. 
For determination of time group delay used spectrum first difference-mode signal 
spectrum. The measurement of the phases signal enables to define the Doppler 
frequency shift. 
Algorithms of data processing are designed. The potential accuracy of 
measurement and frequency range of Doppler Shift measurement are determined. 
The use of the technique allows an enhancement of reliability and an increase of 
information capacity of ionosphere remote sensing with chirped signals.