Abstract: An FSK modulator 20 applies FSK modulation processing to an RF wave supplied from an RF wave oscillator 22, by means of frequency shift keying (FSK) based on a periodical signal sequence supplied from a pattern generator 24, to thereby generate an FSK continuous wave. The continuous wave output from the FSK modulator 20 is delayed in delay circuits 26I and 26Q and is then supplied, as a reference signal, to each of mixers of a receiving mixer 30. Each of the delay circuits 26I and 26Q delays the continuous wave by a delay amount in accordance with a depth of a target position and outputs a delayed reference signal. Thus, demodulation processing is performed with a correlation between a reception signal from the target position and the reference signal being enhanced, and Doppler information from the target position is selectively extracted by a Doppler information analyzing unit 44.

Abstract: A PSK modulator 20 applies digital modulation processing to an RF wave supplied from an RF wave oscillator 22, by means of phase shift keying (PSK) based on a periodical signal sequence supplied from a pattern generator 24, to thereby generate a continuous wave. The continuous wave output from the PSK modulator 20 is delayed in delay circuits 26I and 26Q and is then supplied, as a reference signal, to each of mixers of a receiving mixer 30. Each of the delay circuits 26I and 26Q delays the continuous wave by a delay amount in accordance with a depth of a target position and outputs a delayed reference signal. Thus, demodulation processing is performed with a correlation between a reception signal from the target position and the reference signal being enhanced, and Doppler information from the target position is selectively extracted by a Doppler information analyzing unit 44.

Abstract: A transmission wave corresponding to an FM continuous wave having been subjected to an FM modulation processing is transmitted from a transmitting transducer. A pre-amplifier generates a reception RF signal and outputs the reception RF signal to a receiving mixer. The receiving mixer applies orthogonal detection to the reception RF signal to generate a complex signal. A reference signal supplied to each mixer in the receiving mixer is generated based on an FM continuous wave output from an FM modulator. The FM continuous wave output from the FM modulator is delayed by a delay circuit, and one signal is directly supplied to a mixer whereas the other signal is supplied to a mixer via a ?/2 shift circuit. The delay circuit applies a delay processing in accordance with a depth of a target position within a living organism to the FM continuous wave.

Abstract: An FSK modulator 20 applies FSK modulation processing to an RF wave supplied from an RF wave oscillator 22, by means of frequency shift keying (FSK) based on a periodical signal sequence supplied from a pattern generator 24, to thereby generate an FSK continuous wave. The continuous wave output from the FSK modulator 20 is delayed in delay circuits 26I and 26Q and is then supplied, as a reference signal, to each of mixers of a receiving mixer 30. Each of the delay circuits 26I and 26Q delays the continuous wave by a delay amount in accordance with a depth of a target position and outputs a delayed reference signal. Thus, demodulation processing is performed with a correlation between a reception signal from the target position and the reference signal being enhanced, and Doppler information from the target position is selectively extracted by a Doppler information analyzing unit 44.

Abstract: A PSK modulator 20 applies digital modulation processing to an RF wave supplied from an RF wave oscillator 22, by means of phase shift keying (PSK) based on a periodical signal sequence supplied from a pattern generator 24, to thereby generate a continuous wave. The continuous wave output from the PSK modulator 20 is delayed in delay circuits 26I and 26Q and is then supplied, as a reference signal, to each of mixers of a receiving mixer 30. Each of the delay circuits 26I and 26Q delays the continuous wave by a delay amount in accordance with a depth of a target position and outputs a delayed reference signal. Thus, demodulation processing is performed with a correlation between a reception signal from the target position and the reference signal being enhanced, and Doppler information from the target position is selectively extracted by a Doppler information analyzing unit 44.

Abstract: A transmission wave corresponding to an FM continuous wave having been subjected to an FM modulation processing is transmitted from a transmitting transducer 10. A pre-amplifier 16 generates a reception RF signal and outputs the reception RF signal to a receiving mixer 30. The receiving mixer 30 applies orthogonal detection to the reception RF signal to generate a complex signal. A reference signal supplied to each mixer in the receiving mixer 30 is generated based on an FM continuous wave output from an FM modulator 20. The FM continuous wave output from the FM modulator 20 is delayed by a delay circuit 25, and one signal is directly supplied to a mixer 32 whereas the other signal is supplied to a mixer 34 via a ?/2 shift circuit 26. The delay circuit 25 applies a delay processing in accordance with a depth of a target position within a living organism to the FM continuous wave.