JP2005111131A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve convenience in an ultrasonic diagnostic apparatus by changing-over an imaging method in response to a situation. <P>SOLUTION: The ultrasonic diagnostic apparatus 1 includes: a probe 10, a transmitting part 12, a receiving part 14; an image constituting part 16, and a display part 18. The transmitting part 12 comprises a modulation code changeover part 13 for code-modulating a fundamental waveform and generating a driving signal to drive the probe 10. The receiving part 14 comprises a demodulation code changeover part 15 for code-demodulating a reflection echo signal which the probe 10 receives. The modulation code changeover part 13 and the demodulation code changeover part 15 have a plurality of different modulation/demodulation codes, so as to perform code-modulation/code-demodulation through the use of one selected modulation/demodulation code. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ultrasonic diagnostic apparatus that performs coded transmission / reception.

  The ultrasonic diagnostic apparatus irradiates a subject with ultrasonic waves via a probe and receives a reflected echo signal generated from the subject. Based on the received reflected echo signal, an ultrasonic image (for example, a tomographic image, Doppler image) is reconstructed and displayed.

  In such an ultrasonic diagnostic apparatus, an encoded transmission / reception technique of an ultrasonic pulse signal is employed as one technique for improving the resolution of an ultrasonic image. Based on the modulation / demodulation code, the encoding transmission / reception technology generates a probe drive signal by modulating the basic waveform so that the ultrasonic energy is diffused, and by the probe to converge the ultrasonic energy. By demodulating the received reflected echo signal, the efficiency of ultrasonic energy is improved.

  There are a plurality of types of modulation / demodulation codes of this coding transmission / reception technique. For example, one reflected echo can be obtained by performing two encoded transmissions / receptions using a Barker code or Chirp code (for example, Patent Document 1) that acquires one reflected echo group by one encoded transmission / reception or a complementary orthogonal code pair. A Golay code (for example, Patent Document 2) for acquiring a group has been proposed.

  Each of the modulation / demodulation codes described in Patent Documents 1 and 2 has different characteristics. For example, although the modulation / demodulation code of Patent Document 1 has an advantage that the imaging time is short because the number of transmission / reception times is one, the side lobe remains and the image quality is slightly deteriorated as compared with the technique of Patent Document 2. On the other hand, the modulation / demodulation code of Patent Document 2 has an advantage that the side lobe can be removed by canceling the residual energy by a complementary orthogonal code pair, but when imaging a diagnostic site (for example, heart) with body motion, The side lobes are not offset and the image quality deteriorates.

US Pat. No. 5,147,712 U.S. Pat. No. 4,127,034

  By the way, when performing an ultrasonic diagnosis, the operator moves the probe applied to the body surface of the subject, picks up an ultrasonic image, and displays the ultrasonic image of the part on the display screen to perform the diagnosis. . At this time, the probe is moved relatively quickly until the diagnostic site to be observed appears in the image, and when the probe approaches the site of interest, the probe is stopped to carefully observe the image of the site of interest. In such a process, when searching for a diagnostic site by moving the probe, the resolution of the image may be somewhat worse, but when the imaging time is shortened and the diagnostic site is searched, the image resolution is increased. It is desirable to do.

  Therefore, when the probe is moved, imaging corresponding to the relatively fast movement of the probe is performed, or when the probe is stopped, imaging with high image resolution is performed, When imaging a biological tissue accompanied by body movement, it is desired to further improve the usability by switching the imaging method according to the operator's intention, such as performing imaging suitable for the movement.

  The subject of this invention is changing the imaging method according to a condition and improving the usability of an ultrasonic diagnosing device.

  In order to solve the above problems, an ultrasonic diagnostic apparatus according to the present invention generates a probe that transmits and receives ultrasonic waves to and from a subject, a drive signal that drives the probe, and receives the probe by the probe. A transmission / reception unit that receives the reflected echo signal that is waved, an image configuration unit that reconstructs an ultrasound image based on the received reflection echo signal, and a display unit that displays the reconstructed ultrasound image, The transmission / reception unit code-modulates the basic waveform to generate a drive signal, and includes code modulation / demodulation means for code-demodulating the reflected echo signal received by the probe. A modulation / demodulation code is provided, and code modulation and code demodulation are performed using one selected modulation / demodulation code.

  According to this, one of a plurality of modulation / demodulation codes can be selected and code-modulated. That is, if one modulation / demodulation code is selected, the basic waveform is code-modulated by the selected modulation / demodulation code, and the reflected echo signal is code-demodulated in accordance with the code modulation. Thereby, it can switch to the imaging method according to a condition, and the usability of an ultrasound diagnosing device improves.

  In this case, it is desirable to provide a switch for switching the modulation / demodulation code (for example, a push button switch) on the probe grip. That is, one of the modulation / demodulation codes is selected when the switch is pressed, and the other modulation / demodulation codes are switched to and selected when the switch is released. As a result, the operator can easily switch the modulation / demodulation code by simply operating the switch, and the usability is further improved.

  Also, instead of manually switching the modulation / demodulation code by the operator, the cross-correlation of each reflected echo signal output with a time lag from the transmission / reception unit is analyzed to detect the movement of the diagnostic part, and based on the detection result Thus, it is possible to automatically switch from one selected modulation / demodulation code to another modulation / demodulation code. Thereby, the modulation / demodulation code can be automatically switched according to the characteristics of the diagnostic region to be imaged.

  For example, a time change in the sound pressure of the time sidelobe or a time change in the brightness of the ultrasonic image is detected from each reflected echo signal output with a time shift, and the detection result exceeds the set value. to decide. When the set value is exceeded, it is determined that the diagnostic region to be imaged is accompanied by body movement, and based on the determination result, the modulation / demodulation code suitable for imaging the diagnostic region with body movement is automatically set. Switch automatically.

  In addition, there is provided means having at least one of a function of adding a new modulation / demodulation code to a plurality of modulation / demodulation codes and a function of deleting a specific modulation / demodulation code from the plurality of modulation / demodulation codes. This makes it possible to add or remove a plurality of modulation / demodulation codes held in the code modulation / demodulation means as needed, so that maintenance and inspection of the ultrasonic diagnostic apparatus is facilitated.

  Further, a message representing the selected modulation / demodulation code is displayed on the display unit. Thereby, it is possible to visually grasp the currently selected modulation / demodulation code.

  According to the present invention, the usability of the ultrasonic diagnostic apparatus can be improved by switching the imaging method according to the situation.

  (Embodiment 1) A first embodiment of an ultrasonic diagnostic apparatus to which the present invention is applied will be described with reference to the drawings. The present embodiment is an example in which ultrasonic diagnosis is performed by switching between different types of modulation / demodulation codes. FIG. 1 shows a block diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention. As shown in FIG. 1, the ultrasound diagnostic apparatus 1 includes a probe 10, a transmission unit 12, a reception unit 14, an image processing unit 16, a display unit 18, a control unit 20 that controls each unit, an input unit 21, and the like. Has been.

  The probe 10 is an array of a plurality of transducers that convert electrical signals and transmit ultrasonic waves to the subject, and receive ultrasonic waves from the subject. The transmission unit 12 generates a drive signal for driving the transducer of the probe 10 and includes a modulation code switching unit 13. The modulation code switching unit 13 has a plurality of different types of modulation codes, and selects and switches one modulation code from the plurality of types of modulation codes. The reception unit 14 performs reception processing on the reflected echo signal received by the transducer of the probe 10 and includes a demodulation code switching unit 15. The demodulation code switching unit 15 has a plurality of types of modulation codes, and selects and switches one demodulation code from the plurality of types of demodulation codes. The image processing unit 16 reconstructs an ultrasonic image (for example, a B-mode image, a Doppler image, etc.) based on the reflected echo signal. The display unit 18 displays the ultrasonic image on the display screen of the monitor. The input unit 21 is formed from an input interface such as a keyboard or a mouse.

  The operation of the ultrasonic diagnostic apparatus 1 configured as described above will be described. First, the probe 10 is brought into contact with the body surface of the subject. Then, when a driving signal is supplied to the probe 10 from the transmission unit 12, an ultrasonic wave is emitted from the probe 10 to the irradiation site of the subject. The reflected echo signal generated from the irradiated part propagates through the subject and is received by the probe 10. The received reflected echo signal is subjected to reception processing such as amplification, analog-digital conversion, and phasing addition by the receiving unit 14. The reflected echo signal subjected to the reception processing is subjected to image processing such as logarithmic compression and signal conversion by the image processing unit 16 to be reconstructed into an ultrasonic image. The reconstructed ultrasonic image is displayed on the display screen of the monitor of the display unit 18.

  In such an ultrasonic diagnostic apparatus 1, an encoding transmission / reception technique of an ultrasonic transmission / reception beam is adopted as one technique for improving the resolution of an ultrasonic image. For example, based on the modulation code, the transmission unit 12 generates a drive signal for the probe 10 by code-modulating the basic waveform so that ultrasonic energy is diffused along the time axis and the frequency axis. Further, the receiving unit 14 demodulates the reflected echo signal received by the probe 10 so as to converge the ultrasonic energy on the time axis and the frequency axis based on the demodulation code.

  In the present embodiment, coded transmission / reception is performed using different modulation / demodulation codes of different types. For example, modulation / demodulation codes such as one that obtains a reflected echo group by performing one encoded transmission / reception, and one that obtains a reflected echo group by performing two or more encoded transmission / receptions by a complementary orthogonal code pair are provided. Is available.

  Here, the modulation / demodulation code switching processing of the present invention will be described. FIG. 2 is a configuration diagram of the transmission unit 12 of the present invention, and FIG. 3 is a configuration diagram of the reception unit 14 of the present invention. As shown in FIG. 2, the transmission unit 12 includes transmission timing generation means 40, a modulation code switching unit 13, a power amplifier 42, and the like. The modulation code switching unit 13 includes a plurality of code modulation transmission units 44a to 44m (m: natural number), a code modulation transmission selection unit 46, and the like. Each code modulation transmission means 44a to 44m stores different types of modulation codes.

  In the transmission unit 12 configured as described above, first, a timing signal is generated by the transmission timing generation unit 40. The timing signal is formed from a basic waveform for driving a predetermined number of transducers constituting the aperture of the probe 10. The timing signal is input to the code modulation transmission units 44 a to 44 m and the code modulation transmission selection unit 46 of the modulation code switching unit 13. When a timing signal is input to the code modulation transmission selection means 46, one code modulation transmission means 44a is selected from the code modulation transmission means 44a to 44m by the code modulation transmission selection means 46 based on the set value (α). Is done. The set value (α) is input in advance from the keyboard or mouse of the input unit 21 and is appropriately changed.

  The basic waveform of the timing signal is code-modulated based on the modulation code of the selected code modulation transmission means 44a. The code-modulated signal is amplified by the power amplifier 12 and then transmitted to the probe 10.

  Next, as shown in FIG. 3, the reception unit 14 includes a preamplifier 50, a gain control amplifier 52, a digital / analog conversion unit 54 (hereinafter referred to as an AD conversion unit 54), a phasing addition unit 56, a demodulation code switching unit 15, a band It comprises a filter 58 and the like. The demodulated code switching unit 15 includes a plurality of code demodulation receiving means 60a to 60m, a demodulation code selecting means 62, and the like. Each code demodulation receiving means 60a-60m stores a different demodulated code.

  First, the reflected echo signal received by the probe 10 is amplified by the preamplifier 50. The amplified reflected echo signal is corrected by the gain control amplifier 14 for attenuation caused by propagation and attenuation caused by variable aperture control. The corrected reflected echo signal is quantized to a discrete value by the AD converter 54 and converted into a digital signal. The digitized reflected echo signal is subjected to delay processing on the aperture of the probe 10 at the time of reception by the phasing addition unit 56 and subjected to phasing addition. The reflected echo signal subjected to the phasing addition is input to the code demodulation receiving means 60 a to 60 m and the demodulation code selecting means 62 of the demodulation code switching unit 15. When a reflected echo signal is input to the demodulated code selecting means 62, the demodulated code selecting means 62 selects from the code demodulated receiving means 60a to 60m based on a value (α) preset from the keyboard of the input unit 21 or the like. One code demodulation receiving means 60a is selected. The selected code demodulation receiving means 60a corresponds to the code modulation transmitting means 44a selected by the code modulation transmission selecting means 46 in FIG. Based on the demodulated code of the selected code demodulation receiving means 60a, the waveform of the reflected echo signal is code demodulated. A set frequency component is extracted from the code-demodulated reflected echo signal by the band filter 15 and output to the image processing unit 16.

  According to the present embodiment, based on the set value (α) input from the input unit 21 by the operator, the modulation code switching unit 13 and the demodulation code switching unit 15 perform characteristics of the diagnostic region (for example, dynamic characteristics of the heart). Since the modulation / demodulation code suitable for the measurement type (for example, tomographic image measurement, blood flow image measurement, etc.) is selected from a plurality (m) of modulation / demodulation codes, Usability of ultrasonic diagnostic equipment is improved.

  In addition, a message representing the selected modulation / demodulation code may be generated by the image processing unit 16 based on a command from the control unit 20, and the generated message may be displayed on the display screen of the display unit 18. Thereby, it is possible to visually grasp the currently selected modulation / demodulation code.

  In addition, you may make it provide the transmission / reception part which shared them, without providing the transmission part 12 and the receiving part 14 separately. In this case, the transmission / reception unit includes a code modulation / demodulation unit, and the code modulation / demodulation unit includes a modulation code switching unit 13 and a demodulation code switching unit 15.

  Here, with reference to FIGS. 4 and 5, two types of characteristics of the plurality of modulation / demodulation codes will be described as an example. FIG. 4 is an explanatory diagram of a modulation / demodulation code when imaging a static part, and FIG. 5 is an explanatory diagram of a modulation / demodulation code when imaging a dynamic part. 4 and 5, the code modulation transmission waveform and code demodulation reception waveform of a complementary code represented by Golay code (hereinafter referred to as A code) are shown in the upper part, and the Barker code and Chirp code are shown in the lower part. A code (hereinafter referred to as a B code) that is encoded and transmitted in one transmission / reception is shown. For convenience of explanation, two types of modulation / demodulation codes will be described, but the present invention is not limited to these.

  As shown in FIG. 4, when imaging a site (eg, abdomen) that hardly accompanies body movement, the A code performs, for example, two encoded transmissions of ultrasonic waves using complementary orthogonal code pairs (FIG. 4). 4a). Then, by adding the received reflected echo signals, the energy remaining in the diffusion region is canceled (FIG. 4b). Therefore, the time side lobe 70 is relatively small. On the other hand, with the B code, encoded transmission of ultrasonic waves is performed once (FIG. 4c). Therefore, the imaging time is relatively short. However, energy remains in the diffusion region of the received reflected echo signal, and the remaining energy becomes the time side lobe 72 (FIG. 4d). In order to reduce the time side lobe 72 and converge the diffused energy efficiently, a relatively high-order filter is required, and the circuit scale increases.

  That is, according to the B code, since the number of times of transmission / reception is one, there is an advantage that the imaging time is short. However, since the side lobe remains as compared with the A code, the image quality deteriorates. Therefore, when imaging a static part such as the abdomen, the code modulation transmission selection means 13 selects one modulation code switching unit 44a from the modulation code switching units 44a to 44m and switches to the A code. Similarly, the demodulation code selection means 15 can be switched to the A code. Thereby, if the code modulation / demodulation of the ultrasonic pulse is performed with the A code, the resolution of the ultrasonic image can be increased as compared with the case of the B code.

  In addition, as shown in FIG. 5, when imaging a site (for example, a heart) that accompanies body movement, the A code causes a temporal shift due to the body movement of the heart during the encoded transmission of each ultrasonic pulse. Occurs (FIG. 5a). Therefore, the time side lobe included in the reflected echo signal cannot be canceled (FIG. 5b), and the time side lobe 74 remains (FIG. 5c). In addition, while the encoded transmission / reception is performed twice, the imaging time becomes long. On the other hand, in the B code, since the encoded transmission is performed once, the time side lobe 76 is not affected by the body movement of the heart. It becomes smaller than the case of.

  That is, according to the A code, there is an advantage that when the static part such as the abdomen is imaged, the residual energy can be canceled and the side lobe can be removed. However, when the dynamic part such as the heart is imaged, the B code is used. Compared to this, the time side lobe becomes larger and the image quality deteriorates. Therefore, when imaging the heart or the like or measuring blood flow dynamics, one modulation code switching unit 44b is selected from the modulation code switching units 44a to 44m by the code modulation transmission selection means 13, and the B code is selected. Can be switched to. Similarly, the demodulation code selection means 15 can be switched to the B code. Thus, if the ultrasonic pulse is code-modulated and demodulated with the B code, the imaging time can be shortened compared to the case of the A code, and stable information can be obtained because it is less affected by dynamic changes such as the heart. The resolution of the ultrasonic image is increased.

  (Embodiment 2) A second embodiment to which the present invention is applied will be described. The difference from the first embodiment is that instead of inputting a switching command from the keyboard or mouse of the input unit 21, the switching command is input from a switch provided on the grip unit of the probe 10.

  The probe 10 is provided with a gripping portion that is gripped by an operator by hand on the side opposite to the ultrasonic wave emission surface. For example, a push button type switch is provided in the grip portion. When the switch is pressed, for example, a modulation / demodulation code of A code is selected. Further, when the switch is released, for example, a modulation / demodulation code of B code is selected. As a result, the operator can easily and quickly switch the modulation / demodulation code as compared with the case where a switching command is input from a keyboard, a mouse, or the like, thereby improving the usability of the ultrasonic diagnostic apparatus.

  (Embodiment 3) A third embodiment to which the present invention is applied will be described. The difference from the first embodiment is that the modulation / demodulation code is automatically switched by determining whether or not the diagnosis part is accompanied by body movement.

  An analysis unit is provided after the reception unit 14. The analysis unit analyzes the cross-correlation of each reflected echo signal output from the reception unit 14 with a time shift. For example, the time change of the sound pressure of the time side lobe, the time change of the luminance of the display ultrasonic image, and the like are calculated from each reflected echo signal by the analysis unit. When the calculated value exceeds the set value (β), it is determined that the diagnostic region to be imaged is a dynamic region with body movement. If it is determined that it is a dynamic part, a modulation code suitable for a diagnostic part accompanied by body movement, for example, a B code is automatically selected and switched. As a result, the modulation code can be automatically switched according to the characteristics of the diagnostic region to be imaged, so that the usability of the ultrasonic diagnostic apparatus is improved. The analysis unit is installed at a predetermined position as necessary. That is, it is only necessary that the analysis unit can perform cross-correlation analysis on each reflected echo signal. Further, the set value (β) is appropriately changed by the input unit 21.

  (Embodiment 4) A fourth embodiment to which the present invention is applied will be described with reference to FIGS. The difference from the first embodiment is that the modulation code switching unit 13 and the demodulation code switching unit 15 are configured by software-rewritable components. FIG. 6 is a configuration diagram of the modulation code switching unit 13 in the present embodiment, and FIG. 7 is a configuration diagram of the demodulation code switching unit 15 in the present embodiment.

  As shown in FIG. 6, the modulation code switching unit 13 includes a code modulation transmission unit 80, a code type loading unit 82, a code type storage unit 84, and the like. The code modulation transmission means 80 is from a programmable logic device (PLD) such as SRAM (Static Random Access Memory) or FLASH memory, or a calculation engine (Processor Engine: PE) such as a CPU or DSP (Digital Signal Processor). It is configured. The code type loading means 82 includes a PROM (Programmable Read-Only Memory), a CPLD, and the like. The code type storage means 84 is composed of a storage element such as SRAM or DRAM (Dynamic Random Access Memory). A code type table in which a plurality of types of modulation codes are arranged is stored in the storage element of the code type storage unit 84.

  In the modulation code switching unit 13 configured as described above, first, a read command is generated by the code type loading unit 82 based on a command from the control unit 20. One modulation code is read out from the code type table by the code type storage means 84 based on the generated read command. The read modulation code is written in the code modulation transmission means 80. Based on the written modulation code, the basic waveform output from the transmission timing generation means 40 is code-modulated. The code-modulated transmission signal is output to the power amplifier 42. That is, by writing one modulation code selected from the code type table of the code type storage unit 84 in the code modulation transmission unit 80 according to the purpose such as the diagnostic part and the measurement type, an appropriate modulation code is set according to the situation. To be switched. Thereby, the modulation code switching unit 13 can be simplified and the circuit scale can be reduced.

  As shown in FIG. 7, the demodulated code switching unit 15 includes a code demodulation receiving unit 86, a code type loading unit 88, a code type storage unit 90, and the like. The code demodulation receiving means 86 is from a programmable logic device (PLD) such as SRAM (Static Random Access Memory) or FLASH memory, or a calculation engine (Processor Engine: PE) such as CPU or DSP (Digital Signal Processor). It is configured. The code type loading means 88 includes a PROM (Programmable Read-Only Memory), a CPLD, and the like. The code type storage means 90 is composed of a storage element such as SRAM or DRAM (Dynamic Random Access Memory). A code type table in which a plurality of types of modulation codes are arranged is stored in the storage element of the code type storage unit 90.

  Similarly to the modulation code switching unit 13, the demodulation code switching unit 15 configured as described above writes one demodulated code selected from the code type table of the code type storage unit 90 in the code demodulation reception unit 86, An appropriate demodulation code can be switched according to the situation. The code type loading unit 88 and the code type storage unit 90 may be shared and configured as one device. The same applies to the code type loading unit 82 and the code type storage unit 84.

  (Embodiment 5) A fifth embodiment to which the present invention is applied will be described with reference to FIG. The difference from the first embodiment is that a code type setting means for adding or deleting different types of modulation codes and demodulation codes to the code type table of the fourth embodiment is provided. FIG. 8 shows a block diagram of an ultrasonic diagnostic apparatus according to an embodiment of the present invention.

  As shown in FIG. 8, the code type setting unit 92 is provided to output data and signals to the transmission unit 12 and the reception unit 14 based on a command from the control unit 20. That is, the modulation code input from the input unit 22 is added to the code type table of the code type storage unit 84 by the code type setting unit 92. The modulation code stored in the code type storage unit 84 is deleted from the code type table by the code type setting unit 92 based on a command output from the input unit 22 via the control unit 20. Similarly, demodulated codes are added to or deleted from the code type table of the code type storage means 90. Thereby, since the code type table can be changed according to the situation, maintenance and inspection of the ultrasonic diagnostic apparatus can be easily performed.

  The code type setting unit 92 may be provided with a SCSI interface or a network interface corresponding to TCP / IP. Thereby, even when the modulation code and the demodulation code are stored in an external medium such as an HDD or a network terminal, the modulation code and the demodulation code are stored in the code type table of the code type storage means 84 and 90 via the SCSI interface or the network interface. Can be added.

  As described above, the present invention has been described based on the first to fifth embodiments. However, according to the present invention, when searching for a diagnostic region, a modulation / demodulation code (for example, an imaging time is shortened when the probe is moved) (for example, When (B code) is selected and a diagnostic part is searched, it is possible to switch to a modulation / demodulation code (for example, A code) that increases the image resolution. Therefore, the search time for the site to be diagnosed can be shortened, and the resolution of both the image being searched and the image of the diagnostic site can be made relatively high. As a result, there is an effect that it becomes easy to identify a site to be diagnosed.

1 is a block diagram of an ultrasonic diagnostic apparatus according to a first embodiment of the present invention. FIG. 2 is a configuration diagram of the transmission unit according to the first embodiment. FIG. 3 is a configuration diagram of the receiving unit according to the first embodiment. It is explanatory drawing of the modulation / demodulation code at the time of imaging a static site | part. It is explanatory drawing of the modulation / demodulation code at the time of imaging a dynamic region. It is a block diagram of the modulation code switching part in the ultrasonic diagnosing device of the 4th Embodiment of this invention. It is a block diagram of the demodulation code switching part in the ultrasonic diagnosing device of the 4th Embodiment of this invention. It is a block diagram of the ultrasonic diagnosing device in the 5th Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic diagnostic apparatus 10 Probe 12 Transmission part 13 Modulation code switching part 14 Reception part 15 Demodulation code switching part 16 Image processing part 18 Display part 20 Control part 21 Input part

Claims (2)

A probe for transmitting and receiving ultrasonic waves to and from a subject, a transmission / reception unit for generating a drive signal for driving the probe and receiving a reflected echo signal received by the probe; An image construction unit that reconstructs an ultrasound image based on the received reflected echo signal, and a display unit that displays the reconstructed ultrasound image,
The transmission / reception unit code-modulates a basic waveform to generate the drive signal, and includes code modulation / demodulation means for code-demodulating a reflected echo signal received by the probe,
The ultrasonic diagnostic apparatus, wherein the code modulation / demodulation means has a plurality of different modulation / demodulation codes, and performs the code modulation and the code demodulation using a selected modulation / demodulation code. Cross-correlation analysis is performed on each reflected echo signal output with a time lag from the transmission / reception unit to detect the movement of the diagnostic part, and based on the detection result, the selected modulation / demodulation code is used to generate another modulation / demodulation code. The ultrasonic diagnostic apparatus according to claim 1, wherein the ultrasonic diagnostic apparatus is switched to a code.

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