Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
127 words
In an ultrasonic Doppler diagnostic apparatus wherein an ultrasonic pulse beam of a given fixed pulse-recurrence frequency is transmitted into a subject and detection of the distance to the moving reflective member and the velocity of the moving reflective member are detected by comparing transmitted and received signals, the improved apparatus further comprising a memory for storing a first velocity distribution obtained from a first signal received from a given direction, and a tangential velocity calculator for calculating a tangential velocity distribution in a direction tangential to an arc of a scanned sector by comparing said first velocity distribution with a second velocity distribution obtained from a second signal received from a direction deflected by a minute angle with respect to the direction of the first signal.
Claim 2
Dependent Claim
127 words
In an ultrasonic Doppler diagnostic apparatus wherein an ultrasonic pulse beam of a given fixed pulse-recurrence frequency is transmitted into a subject and detection of the distance to the moving reflective member and the velocity of the moving reflective member are detected by comparing transmitted and received signals, the improved apparatus further comprising a memory for storing a first velocity distribution obtained from a first signal received from a given direction, and a tangential velocity calculator for calculating a tangential velocity distribution in a direction tangential to an arc of a scanned sector by comparing said first velocity distribution with a second velocity distribution obtained from a second signal received from a direction deflected by a minute angle with respect to the direction of the first signal.
Claim 3
Dependent Claim
167 words
In an ultrasonic Doppler diagnostic apparatus wherein an ultrasonic pulse beam of a given fixed pulse-recurrence frequency is transmitted into a subject and detection of the distance to the moving reflective member and the velocity of the moving reflective member are detected by comparing transmitted and received signals, the improved apparatus further comprising a complex signal converter for converting a received signal into complex signals, an autocorrelator for establishing a delay equal to an integer multiple of a transmitted pulse rate period and calculating the autocorrelation of said complex signals, a memory for storing a first autocorrelation signal output by said autocorrelator and relating to a first signal received from a given direction, and a tangential velocity calculator for calculating a tangential velocity distribution in a direction tangential to an arc of a scanned sector by comparing said first autocorrelation with a second autocorrelation obtained from a second signal received from a direction deflected by a minute angle with respect to the direction of the first signal.
Claim 4
Dependent Claim
167 words
In an ultrasonic Doppler diagnostic apparatus wherein an ultrasonic pulse beam of a given fixed pulse-recurrence frequency is transmitted into a subject and detection of the distance to the moving reflective member and the velocity of the moving reflective member are detected by comparing transmitted and received signals, the improved apparatus further comprising a complex signal converter for converting a received signal into complex signals, an autocorrelator for establishing a delay equal to an integer multiple of a transmitted pulse rate period and calculating the autocorrelation of said complex signals, a memory for storing a first autocorrelation signal output by said autocorrelator and relating to a first signal received from a given direction, and a tangential velocity calculator for calculating a tangential velocity distribution in a direction tangential to an arc of a scanned sector by comparing said first autocorrelation with a second autocorrelation obtained from a second signal received from a direction deflected by a minute angle with respect to the direction of the first signal.
Claim 5
Dependent Claim
25 words
An ultrasonic Doppler diagnostic apparatus according to either one of claims 1 and 2 wherein said tangential velocity calculator calculates the conjugate of the autocorrelations.
Claim 6
Dependent Claim
21 words
An ultrasonic Doppler diagnostic apparatus according to claim 3 wherein said tangential velocity calculator calculates the imaginary component of the conjugate.
Claim 7
Dependent Claim
36 words
An ultrasonic Doppler diagnostic apparatus according to either one of claims 1 and 2 further comprising a vector calculator for calculating the velocity of the moving reflective member from the output of said tangential velocity calculator.
Claim 8
Dependent Claim
38 words
An ultrasonic Doppler diagnostic apparatus according to claim 5 wherein a vector angle calculated by said vector calculator is compensated by use of the scanning angle into an angle with respect to the reference direction of sector scanning.
Claim 9
Dependent Claim
58 words
An ultrasonic Doppler diagnostic apparatus according to claim 5 wherein said vector calculator calculates the absolute vectorial velocity as the square root of the sum of the square of the tangential velocity obtained as the output of said tangential velocity calculator and the square of the radial velocity of the moving reflective member obtained from said received signal.
Claim 10
Dependent Claim
56 words
An ultrasonic Doppler diagnostic apparatus according to claim 5 wherein said vector calculator calculates the direction of the vectorial velocity from the inverse tangent of the quotient obtained by dividing the tangential velocity obtained as the output of said tangential velocity calculator by the radial velocity of the moving reflective member obtained from the received signal.