JP3000791B2 - Ultrasound diagnostic equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic diagnostic apparatus having a digital beam synthesizer.

[0002]

2. Description of the Related Art Recently, there has been known an ultrasonic diagnostic apparatus which performs A / D (analog / digital) conversion of an ultrasonic reception signal and synthesizes reception directivity. This ultrasonic diagnostic apparatus is known from Japanese Patent Application Laid-Open No. 61-8039, and its operation principle will be described below with reference to a schematic block diagram shown in FIG.

In FIG. 5, four vibrators T-1 to T-1
The example using -4 is shown. As shown in FIG. 5, a pulsar trigger signal from the control unit 51 is input to four pulsar receivers 52-1 to 52-4. The pulser trigger signal is phase-controlled to perform electron focusing and sector scanning. Four pulsar receivers 52-1 to 52-4
Outputs a drive pulse for driving the vibrators T-1 to T-4 according to the pulsar trigger signal. The vibrators T1 to T4 are
The ultrasonic wave is transmitted in the direction set by the drive pulse. The ultrasonic waves reflected in the subject are transmitted to the same transducers T-1 to T-1.
It is received at T-4 and converted into an electric signal. This electric signal is amplified by each of the pulsar receivers 52-1 to 52-4 and sent to A / D converters 53-1 to 53-4. Each A / D
The received signals converted into digital signals by the converters 53-1 to 53-4 are phase-controlled by the phase adjusters 54-1 to 54-4 so that the receiving sensitivity is maximized in the direction in which the ultrasonic wave is transmitted. Are added by the adder 55 and the scan converter 5
Sent to 6. Inside the scan converter 56, the digital signal from the adder 55 is detected and displayed on the display 57 as a tomographic image.

[0004]

However, in the ultrasonic diagnostic apparatus having the above-mentioned conventional digital beam synthesizing unit, when the dynamic range of the received signal is extremely large as in the CW Doppler mode or the like, high accuracy and high cost are required. There is a problem that it is necessary to use an appropriate A / D converter.

The present invention has been made to solve such a conventional problem, and has a high sensitivity even in a CW Doppler mode or the like while having a digital beam synthesizing section constituted by a low-resolution A / D converter. It is an object of the present invention to provide an ultrasonic diagnostic apparatus capable of performing phase detection.

[0006]

According to a first aspect of the present invention, there is provided a digital beam synthesizing unit for digitally converting a received signal obtained from an arrayed vibrator and synthesizing a reception directivity. A quadrature signal generator for outputting data, a digital mixer for multiplying the output of the digital beam combiner with the quadrature data output from the quadrature signal generator, an analog reception signal obtained from a single oscillator, and the quadrature signal And an analog mixer that multiplies the orthogonal signal obtained from the output data of the generator.

According to a second aspect of the present invention, there is provided a digital beam synthesizing unit for performing digital conversion of a reception signal obtained from an arrayed oscillator and synthesizing reception directivity, and an orthogonal signal for outputting orthogonal data. A digital mixer for multiplying the output of the digital beam combining unit by the orthogonal data output from the orthogonal signal generating unit; and an analog reception signal obtained from a single oscillator and the output data of the orthogonal signal generating unit. An analog mixer for multiplying the obtained quadrature signal, an A / D converter for converting an output of the analog mixer into digital data, and a selector for selecting an output of the A / D converter and an output of the digital mixer. It is provided.

According to a third aspect of the present invention, in order to achieve the above object, there is provided an analog beam combining section for combining reception directivity of a reception signal obtained by an arrayed oscillator according to the first or second aspect of the invention, The output of the analog beam combining section is configured to be applied to an analog mixer.

According to a fourth aspect of the present invention, in order to achieve the above object, in any one of the first to third aspects,
The output of the digital mixer and the output of the quadrature signal generator are obtained through a common data bus.

According to a fifth aspect of the present invention, in order to achieve the above object, in any one of the first to fourth aspects of the present invention,
A D / A converter for the output data of the quadrature signal generator is provided, and the output of the D / A converter is applied to an analog mixer.

[0011]

Therefore, according to the first aspect of the present invention, the reception signal in the B mode or the pulse Doppler mode from the arrayed oscillators is phase-detected by the digital mixer via the digital beam synthesizing unit, and the single oscillator is received. The received signal in the pulse Doppler mode or the CW Doppler mode is phase-detected by an analog mixer via an analog receiving circuit. Then, since the quadrature signal inputs of the digital mixer and the analog mixer are controlled in common,
High sensitivity phase detection can be realized.

According to the second aspect of the present invention, the received signal in the B mode or the pulse Doppler mode from the arrayed oscillators is digitally phase-detected via the digital beam synthesizing section, and the pulse Doppler from the single oscillator is output. Alternatively, the received signal in the CW Doppler mode is phase-detected via an analog receiving circuit, and the outputs of the digital mixer and the analog mixer are selected by a selector and signal-processed by a common circuit. It can be realized with a small signal processing circuit.

According to the third aspect of the present invention, the reception signal in the B mode or the pulse Doppler mode from the arrayed oscillators is phase-detected by the digital mixer via the digital beam synthesizer, and is output from the single oscillator. The received signal in the pulse Doppler or CW Doppler mode passes through the analog receiving circuit, and the CW
Since the Doppler mode reception signal is phase-detected by the analog mixer via the analog beam synthesis unit, high-sensitivity phase detection can be realized.

According to the fourth aspect of the present invention, the output of the digital mixer and the output of the quadrature signal generator can be obtained via the common data bus, and the circuit can be downsized.

According to the fifth aspect of the present invention, a D / A converter for the output data of the quadrature signal generator is provided.
Since the output of the converter is input to the analog mixer, highly accurate analog phase detection can be realized with a small circuit.

[0016]

【Example】

Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic block diagram showing an ultrasonic diagnostic apparatus according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes an array-type ultrasonic probe, which includes N transducers T-1 to TN. In the present embodiment, N = 4 for simplicity of explanation. 2-
1-2-4 are pulse generators (hereinafter referred to as pulsers) connected to the oscillators T-1 to T-4, and 3-1 to 3-4 are connected to outputs of the pulsers 2-1 to 2-4. 4 is a digital beam combining section connected to the outputs of the amplifiers 3-1 to 3-4, 5 is an orthogonal signal (orthogonal data) generating section, 6 is a digital mixer, and multipliers 7-1 and 7 are provided. -2, which is connected to the output of the digital beam combiner 4 and to which the output data of the quadrature signal generator 5 is added. 8-1, 8
Reference numeral -2 denotes a low-pass filter connected to the outputs of the multipliers 7-1 and 7-2, and reference numeral 9 denotes an ultrasonic probe, which in this case is constituted by a single element type transducer. 10 is a pulsar connected to the vibrator 9, 11 is an amplifier connected to the output of the pulsar 10, 12 is an analog beam combiner connected to the outputs of the amplifiers 3-3 and 3-4, 13 is the amplifier 11 and the analog A switch for selecting the output of the beam combining unit 12, 1
Reference numeral 4 denotes an analog mixer, which includes multipliers 15-1 and 15-2.
And connected to the output of the amplifier 11 or the analog beam combining unit 12 via the switch 13, and the COS / SI obtained from the output data of the quadrature signal generating unit 5.
An N signal is applied. 16-1 and 16-2 are multipliers 15
Low-pass filters connected to the outputs of -1, 15-2,
17-1 and 17-2 are low-pass filters 16-1 and 16-1
A / D converter (hereinafter, referred to as A / D) connected to the output of A-2, 18 is a low-pass filter 8-1, 8-2, A / D
Selectors connected to the outputs of D17-1 and 17-2, 1
9 is a signal processing unit connected to the output of the selector 18;
Is a scanning converter connected to the output of the signal processing unit 19, 21
Is a display unit connected to the output of the scan converter 20, and 22 is a control unit for controlling the pulsars 2-1 to 2-4, 10, the digital beam combining unit 4, and the quadrature signal generating unit 5.

FIG. 2 is a schematic block diagram showing the digital beam combining section 4. As shown in FIG. 2, the digital beam combiner 4 includes A / D converters (hereinafter, referred to as A / D) 23-1 to 23-4 and first-in first-out memories (hereinafter, referred to as FIFO) 24-. 1 to 24
-4 and an adder 25.

FIG. 3 is a schematic block diagram showing the analog beam combining section 12. As shown in FIG. As shown in FIG. 3, the analog beam combining unit 12 includes a cross point switch 26 and a tapped delay line 27.

The above configuration and its operation will be described in more detail below. First, a trigger signal from the control unit 22 is input to the four pulsers 2-1 to 2-4.
The trigger signal is phase-controlled to perform electron focusing and sector scanning. The four pulsars 2-1 to 2-4 generate a drive pulse in response to a trigger signal, and the oscillator T-
1 to T-4 are driven. The vibrators T-1 to T-4 are driven by the pulsars 2-1 to 2-4, and transmit ultrasonic waves in a set direction. The ultrasonic waves reflected in the subject are received by the same transducers T-1 to T-4 and converted into electric signals.
This electric signal is amplified by the amplifiers 3-1 to 3-4 and sent to the A / Ds 23-1 to 23-4 of the digital beam combining unit 4. The received signals converted into digital signals by the A / Ds 23-1 to 23-4 are FIFO24-1 to FIFO24-24.
-4 is written. The data written in the FIFOs 24-1 to 24-4 is read out with controlled timing so that the receiving sensitivity becomes maximum in the direction in which the ultrasonic wave is transmitted. By shifting the read and write timings of the FIFOs 24-1 to 24-4, they can be used as variable delay elements. The read data is added to the adder 25.
Are added. The outputs of the adder 25 obtained as described above are output to the multipliers 7-1 and 7 of the digital mixer 6.
At -2, the signal is multiplied by the digital quadrature signal from the quadrature signal generator 5, that is, the COS / SIN data. The output of the multipliers 7-1 and 7-2 is a low-pass filter 8
-1 and 8-2 to become I and Q signals, and the selector 1
The signal is input to the signal processing unit 19 through 8-1 and 18-2. In the signal processing unit 19, the I and Q signals are in B mode,
Signal processing according to each scanning mode of pulse Doppler and color flow is performed. The output of each scanning mode processed by the signal processing unit 19 is converted into a TV signal by the scanning converter 20 and displayed on the display unit 21.

On the other hand, there is a steerable CW Doppler (hereinafter referred to as SCW) mode as another scanning mode. Next, the operation in the SCW mode will be described. In the SCW mode, a continuous clock signal is sent from the control unit 22 to the two pulsers 2-1 and 2-2. This trained clock signal is
Phase control is performed to perform electron focusing and sector scanning. The two pulsers 2-1 and 2-2 generate a continuous wave drive signal by the continuous wave clock signal, and output the oscillators T-1 and T-.
2 is driven. The oscillators T-1 and T-2 are pulsars 2-1,
It is driven by 2-2 and transmits ultrasonic waves in a set direction. The ultrasonic wave reflected inside the subject is transmitted to another transducer T-
3. Received at T-4 and converted to electrical signals. This electric signal is amplified by the amplifiers 3-3 and 3-4 and input to the analog beam combining unit 12. The signals from the amplifiers 3-3 and 3-4 are input to predetermined taps of the tapped delay line 27 by the cross point switch 26 of the analog beam combining unit 12 according to the directivity of reception. The output of the analog beam combining unit 12 is selected by the switch 13,
The signals are input to the multipliers 15-1 and 15-2 of the analog mixer 14 and output from the quadrature signal generator 5, that is, C
Analog multiplication is performed with the OS / SIN signal. This COS /
The SIN signal is the COS / SIN for the multipliers 7-1 and 7-2.
The data can be obtained by D / A conversion, or by using a signal of the most significant bit of COS / SIN data instead. The outputs of the analog mixer 14 obtained as described above are output to the low-pass filters 16-1 and 16-1.
-2, and is converted into digital data by A / D converters 17-1 and 17-2, and selectors 18-1 and 18-2
, And frequency-analyzed by the signal processing unit 19,
The data is sent to the scan converter 20 as CW mode data and displayed on the display unit 21.

On the other hand, when obtaining a signal from the ultrasonic probe 9, a trigger signal from the control unit 22 is input to the pulser 10. The pulser 10 generates a drive pulse according to the trigger signal and drives the ultrasonic probe 9. Ultrasonic probe 9
Is driven by the pulsar 10 and transmits ultrasonic waves. The ultrasonic wave reflected in the subject is received by the ultrasonic probe 9,
Converted to electrical signals. This electric signal is amplified by the amplifier 11, selected by the switch 13, and input to the multipliers 15-1 and 15-2 of the analog mixer 14. The outputs of the multipliers 15-1 and 15-2 are supplied to a low-pass filter 16-
1, 16-2, and A / D converters 17-1, 17-
2, the data is converted into digital data.
18-2, the signal processing unit 19 selects the B mode,
Signal processing is performed according to each scanning mode such as pulse Doppler, CW Doppler, and color flow. The output of each scanning mode processed by the signal processing unit 19 is output to the scan converter 20.
Is converted into a TV signal and displayed on the display unit 21.

As described above, according to the above-described embodiment, the reception signals in the B mode or the pulse Doppler mode from the arrayed oscillators T-1 to T-4 are transmitted to the digital mixer 6 via the digital beam synthesis unit 4. Phase detected,
The received signal in the pulse Doppler or CW Doppler mode from the single oscillator 9 is phase-detected by the analog mixer 14 via the analog receiving circuit, and the quadrature signals of the digital mixer 6 and the analog mixer 14 are commonly controlled. Therefore, there is an advantage that high-sensitivity and high-accuracy phase detection can be realized.

Also, B from the arrayed oscillators T-1 to T-4
The received signal in the mode or the pulse Doppler mode is phase-detected by the digital mixer 6 via the digital beam combiner 4, and the received signal in the pulse Doppler or the CW Doppler mode from the single oscillator 9 is passed through the analog receiving circuit. The phase is detected by the analog mixer 14, and the outputs of the digital mixer 6 and the analog mixer 14 are selected by the selectors 18-1 and 18-2 and signal-processed by a common circuit. This has the advantage that it can be realized by the signal processing circuit of the above.

Further, B from the arrayed oscillators T-1 to T-4
The received signal in the mode or the pulse Doppler mode is phase-detected by the digital mixer 6 via the digital beam combiner 4, and the received signal in the pulse Doppler or the CW Doppler mode from the single oscillator 9 is passed through the analog receiving circuit. And the array transducers T3, T4
The steerable CW Doppler mode received signal from the analog signal is subjected to a phase detection circuit by the analog mixer 14 via the analog beam synthesizing unit 12, so that there is an advantage that high-sensitivity phase detection can be realized.

(Embodiment 2) Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 4 shows an ultrasonic diagnostic apparatus according to a second embodiment of the present invention, and is a schematic block diagram of a peripheral portion of a digital mixer. In FIG. 4, reference numeral 28 denotes multipliers 7-1 and 7-2 of the digital beam combiner 4 and the digital mixer 6.
Are connected between the multipliers 7-1 and 7-2 of the digital mixer 6 and the multipliers 15-1 and 15-2 of the analog mixer 14. D / A converter (hereinafter referred to as D / A). The output buses B1 and B2 of the multipliers 7-1 and 7-2 are called a common data bus. Other configurations are the same as those in the first embodiment.

The above configuration and its operation will be described in more detail below. Digital beam combining unit 4
, The selector 28 selects the output of the digital beam combiner 4 and the output of the selector 28 is input to the multipliers 7-1 and 7-2 of the digital mixer 6 and 5 is multiplied by the COS / SIN output. The outputs of the multipliers 7-1 and 7-2 pass through the common data buses B1 and B2, and are signal-processed through the low-pass filters 8-1 and 8-2 in the same manner as above. On the other hand, when operating the analog mixer 14, the selector 28 selects the data “1” and outputs the data “1”. Multiplier 7
At -1, the COS data of the orthogonal signal generator 5 is multiplied by data "1", and COS data is output. The multiplier 7-2 multiplies the SIN data of the orthogonal signal generator 5 by data "1" and outputs SIN data. The COS data output from the multiplier 7-1 is supplied to the common data bus B
1 and input to the D / A 29-1, and the SIN data output from the multiplier 7-2 is input to the D / A 29-2 through the common data bus B2. The COS signal output from the D / A 29-1 is output to the multiplier 19 of the analog mixer 18.
-1 and the SIN signal output from the D / A 29-2 is input to the multiplier 19-2 of the analog mixer 18. Outputs of the multipliers 19-1 and 19-2 are processed through low-pass filters 20-1 and 20-2 in the same manner as described above.

As described above, according to this embodiment, the output of the digital mixer 6 and the output of the quadrature signal generator 5 are obtained via the common data buses B1 and B2, and the number of data buses can be reduced. Has advantages. In particular, when the orthogonal signal generator 5 and the multipliers 7-1 and 7-2 are formed as one integrated circuit, the effect of reducing the number of pins of the integrated circuit by reducing the data bus is great.

Further, D / A converters 29-1 and 29-2 for the output data of the orthogonal signal generator 5 are provided.
The output of the A converters 29-1 and 29-2 is the analog mixer 1
4 has the advantage that highly accurate analog phase detection can be realized with a small circuit.

[0031]

As described above, according to the first aspect of the present invention, the reception signal in the B mode or the pulse Doppler mode from the arrayed oscillator is phase-detected by the digital mixer via the digital beam synthesizing unit. A received signal in a pulse Doppler or CW Doppler mode from a single oscillator is phase-detected by an analog mixer via an analog receiving circuit. Then, since the quadrature signal inputs of the digital mixer and the analog mixer are controlled in common, high-sensitivity and high-accuracy phase detection can be realized.

According to the second aspect of the present invention, the reception signal in the B mode or the pulse Doppler mode from the arrayed oscillators is phase-detected by the digital mixer via the digital beam synthesizing section, and is output from the single oscillator. The received signal in the pulse Doppler or CW Doppler mode is phase-detected by an analog mixer via an analog receiving circuit, and the outputs of a digital mixer and an analog mixer are selected by a selector and signal processed by a common circuit. Sensitivity phase detection can be realized with a small signal processing circuit.

According to the third aspect of the present invention, the received signal in the B mode or the pulse Doppler mode from the arrayed oscillators is phase-detected by the digital mixer via the digital beam synthesizing section, and is output from the single oscillator. The received signal in the pulse Doppler or CW Doppler mode passes through an analog receiving circuit, and the steerable CW Doppler mode received signal from the arrayed vibrator is phase-detected by an analog mixer via an analog beam synthesizing unit. Can be realized.

According to the fourth aspect of the present invention, in addition to performing high-sensitivity phase detection, the output of the digital mixer and the output of the quadrature signal generator can be obtained via the common data bus. The number can be reduced.

According to the fifth aspect of the present invention, there is provided a D / A converter for the output data of the quadrature signal generator,
Since the output of the converter is input to the analog mixer, highly accurate analog phase detection can be realized with a small circuit.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing an ultrasonic diagnostic apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic block diagram showing a digital beam combining unit of the apparatus.

FIG. 3 is a schematic block diagram showing an analog beam combining unit of the apparatus.

FIG. 4 is a schematic block diagram of a peripheral portion of a digital mixer, showing an ultrasonic diagnostic apparatus according to a second embodiment of the present invention.

FIG. 5 is a schematic block diagram showing a conventional ultrasonic diagnostic apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrasonic probe T1-T4 Transducer 4 Digital beam synthesizer 5 Quadrature signal generator 6 Digital mixer 9 Ultrasonic probe 12 Analog beam synthesizer 14 Analog mixer 18-1 Selector 18-2 Selector

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-206445 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61B 8/00-8/15

Claims (5)

(57) [Claims] 1. A digital beam combining section that converts a received signal obtained from an arrayed transducer into a digital signal and combines reception directivity, an orthogonal signal generating section that outputs orthogonal data,
A digital mixer for multiplying the output of the digital beam synthesizing unit with the orthogonal data output from the orthogonal signal generation unit; and a quadrature obtained from the analog reception signal obtained from the single oscillator and the output data of the orthogonal signal generation unit. An ultrasonic diagnostic apparatus comprising an analog mixer for multiplying a signal. 2. A digital beam synthesizing unit for performing digital conversion of a reception signal obtained from an arrayed oscillator and synthesizing reception directivity, an orthogonal signal generation unit for outputting orthogonal data,
A digital mixer for multiplying the output of the digital beam synthesizing unit with the orthogonal data output from the orthogonal signal generation unit; and a quadrature obtained from the analog reception signal obtained from the single oscillator and the output data of the orthogonal signal generation unit. An analog mixer for multiplying a signal, an A / D converter for converting an output of the analog mixer into digital data,
An ultrasonic diagnostic apparatus comprising an output of a D converter and a selector for selecting an output of the digital mixer. 3. An ultrasonic wave according to claim 1, further comprising an analog beam combining section for combining reception directivity of the reception signals obtained by the arrayed transducers, wherein an output of the analog beam combining section is applied to an analog mixer. Diagnostic device. 4. The ultrasonic diagnostic apparatus according to claim 1, wherein an output of the digital mixer and an output of the quadrature signal generator are obtained via a common data bus. 5. The method according to claim 1, wherein D is a value corresponding to the output data of the orthogonal signal generator.
5. The ultrasonic diagnostic apparatus according to claim 1, further comprising an A / A converter, wherein an output of the D / A converter is applied to an analog mixer.