| 摘要 |
PROBLEM TO BE SOLVED: To provide improved technologies for extracting Doppler information from a target position by utilizing continuous waves. SOLUTION: An FSK modulator 20 subjects RF waves fed from an RF oscillator 22 to the digital modulation process, and generates continuous waves by the frequency shift keying (FSK) based on a periodic signal string fed from a pattern generator 24. The continuous waves output from the FSK modulator 20 are delayed by a delay circuit 26I and a delay circuit 26Q, and fed to mixers of a receiving mixer 30 as reference signals. The delay circuit 26I and delay circuit 26Q delay the continuous waves by a quantity of delay corresponding to the depth of the target position, and output delayed reference signals. Then, the correlation between receiving signals from the target position and the reference signals is intensified and the signals are demodulated, and Doppler information from the target position is selectively extracted by a Doppler information analysis part 44. COPYRIGHT: (C)2010,JPO&INPIT |
