Potential of radar pulse strobing scheme use in phase-sensitive operation mode

The mathematical model of a radr pulse stroboscopic transformer is considered which consists of a multiplier and a narrow-band filter tuned to the carrier difference frequency. Additional capabilities of the transformer are studied which allow extending its application area when performing phase measurements of short radar signals. An asymptotical approach to analysis is used which implies a large time scale transformation coefficient and strobing radar impulse duration much smaller than the input signal duration. It is shown that shifting the strobing radar impulse carrier frequency by the value of the repetition frequency's first subharmonic allows transformation of the signal's phase structure into envelope modulation without employing additional phase-sensitive elements. Measurements of the phase structure can then be conducted on the low intermediate frequency with amplitude methods. Results of seminatural modelling of the phase-sensitive mode of stroboscopic transformer operation are shown, which are obtained on an experimental model based on ATmega16 and STM32F407 microcontrollers and a PC. It is shown that when the clock frequency of the system is synchronized to the second harmonic of the difference frequency, the envelope of the transformed signal gains additional linear phase modulation, which is independent of the spectral transformation coefficient and is solely determined by the signal's duty cycle.