CN101354437B - Ultrasonic diagnostic apparatus - Google Patents

Abstract

The ultrasonic diagnostic apparatus of the present invention comprises: a probe which transmits and receives ultrasonic waves to and from an object to be inspected, a transmission means which outputs transmission signals for driving the probe, a reception means which processes reception signals received by the probe and obtains reception signals whose higher-order harmonics are reinforced, and an image reconstruction means which reconstructs higher-order harmonic images of an ultrasonogram using the reception signals outputted by the reception means. The transmission means creates and outputs the transmission signals corresponding to a composite modulation code sequence, composed from two or more modulation code sequences and taking the phase offset of corresponding base wave as coding elements. The reception means is provided with a demodulator which demodulates the modulation based on the composite modulation code sequence for the reception signals. By using a composite modulation code sequence taking the phase offset of corresponding base wave as coding elements, it becomes possible to obtain reception signals whose higher-order harmonics are reinforced. In addition, a circuit scale of the circuit is reduced and the side lobe reduction effect can be obtained, as the demodulators is divieded into two or more stages.

Description

Diagnostic ultrasound equipment

The application is that application number is " 200480035737.1 ", and the applying date is on Dec 1st, 2004, and denomination of invention is divided an application for the application of " diagnostic ultrasound equipment ".

Technical field

The present invention relates to encode and receive the diagnostic ultrasound equipment that sends.

Background technology

Diagnostic ultrasound equipment, by by sending part to the probe output drive signal, transmit hyperacoustic while by probe to object to be detected, receive the reflection echo signal that produces by object to be detected by probe, according to the signal that receives, reconstruct ultrasound wave picture.Probe is made of vibrator array, when receiving ultrasound wave, postpones the received signal of each Vib. by addition every the stipulated time, can control hyperacoustic focal position in the object to be detected.Method by change delay time moving focal point position is called as dynamic focusing.

In diagnostic ultrasound equipment, hyperacoustic waveform of transmission in order to improve range resolution, wishes that at time-axis direction be short pulsating wave, and, in order to improve SN, wish to use the big waveform of signal intensity than (Signal NoiseRatio).But, owing to the maximal value of ultrasonic intensity need be suppressed to the degree that biosome is not exerted an influence, suppress hyperacoustic maximum intensity on one side, increase on one side and send energy, the coding transmission technology of popularizing in field of radar is suitable in diagnostic ultrasound equipment, and for example the spy opens that flat 2003-No. 225237 communiques etc. are put down in writing.In this technology, by the big single pulse waveforms of coding peak strength, be diffused on the signal train of the little time-axis direction of each peak strength, send to object to be detected, after being received in the signal of object to be detected internal reflection, to converge to the decoding processing on the time-axis direction by demodulator filter, recover the big pulse waveform of peak strength.

As symbol, can use well-known Bark (Barker) sign indicating number or Gray (Golay) sign indicating number etc. in field of radar, can use the autocorrelation filter device that carries out auto-correlation processing or the wave filter etc. that do not match at decoding filter.

Patent documentation 1: the spy opens flat 2003-No. 225237 communiques.

But, coding in the past receives in the transmission technology, have when assembling coding by decoding to the ultrasonic energy of time-axis direction diffusion, be created in the residual ultrasonic energy in front and back of the time-axis direction of the pulse waveform that should obtain, generation is called as problem time sidelobe, unwanted signal.By using the big high order wave filter of operation times (exponent number), can reduce time sidelobe, but as long as operation times increases, circuit scale just increases as demodulator filter.

In addition, spread expeditiously in order to make ultrasonic energy, if increase the quantity of coding elements, the quantity of corresponding coding elements, received signal is elongated at time-axis direction.Therefore, the hand-off process that the focus section switching of dynamic focusing etc. are interrupted, the possibility of carrying out during received signal increases, exist be accompanied by hand-off process in received signal with high level generation time secondary lobe phenomenon.

Summary of the invention

Problem of the present invention is to realize suppressing the increase of circuit scale, and the coding that reduces time sidelobe simultaneously receives transmission.

In order to solve above-mentioned problem, diagnostic ultrasound equipment of the present invention has: send between object to be detected and receive hyperacoustic probe; Output is used to drive the sending part of the transmission signal of probe; Handle the acceptance division of the received signal of probe reception; And the image construction portion that uses the receiving signal reconstruction ultrasound wave picture of acceptance division output.Sending part is made, output and the corresponding transmission signal of synthetic modulation code sequence that synthesizes a plurality of modulation code sequences.Acceptance division possesses the detuner of the modulation that demodulation to received signal undertaken by synthetic modulation code sequence.By using the synthetic modulation code sequence of synthetic a plurality of modulation code sequences, detuner is configured in multistage like this, can separates step by step and be mixed into modulation code sequence.Therefore, by the circuit scale of the computing circuit number that adds up to the multistage detuner, can access the equal secondary lobe of circuit number that the computing circuit number with the multistage detuner multiplies each other and reduce effect.

Above-mentioned sending part can constitute based on the coding elements coefficient according to synthetic modulation code sequence, and output waveform generates and sends signal successively.

In addition, above-mentioned synthetic modulation code sequence can use synthetic the 1st modulation code sequence and the 2nd modulation code sequence sign indicating number sequence afterwards.At this moment, the formation of acceptance division has: be used for the 1st detuner of the modulation that demodulation to received signal undertaken by the 1st modulation code sequence, be used for the 2nd detuner of the modulation that demodulation to received signal undertaken by the 2nd modulation code sequence.Received signal is carried out further demodulation by another detuner again by after the detuner demodulation of the 1st and the 2nd detuner.

At this moment, as the encoded interval of the 1st modulation code sequence, can use bigger than the encoded interval of the 2nd modulation code sequence.At this moment, can be as the 1st detuner, compare with the 2nd detuner and to be configured near the probe side, by the received signal of probe output, after the 1st detuner demodulation, further carry out demodulation by the 2nd detuner.Thus, because the big modulation code of at first demodulation encoded interval, can reduce then by implementing discontinuous processing, for example the demodulation mistake of the influence of the switching of the switching of the switching of focus section or numerical aperture or magnification generation can reduce the time sidelobe that is produced by discontinuous processing.

For example, the 1st detuner can be configured in the position that the received signal of put in order by the whole phase addition portion that carries out that the focus section switches before the phase addition is carried out demodulation, the 2nd detuner is configured in putting in order the position that received signal after the phase addition is carried out demodulation process by putting in order phase addition portion.Thus, can reduce by the focus section and switch the demodulation mistake that produces, can reduce time sidelobe.And,, also can reduce circuit scale significantly by the 2nd detuner being configured in whole phase addition portion back segment.

In addition, also can all be configured in carry out the position of demodulation process by the received signal after the whole phase addition of whole addition portion with the 2nd detuner the 1st.At this moment because the 1st and the 2nd detuner as long as each 1 just can, circuit scale can reduce significantly.

In addition, also can be configured in the position to carrying out demodulation respectively with the 2nd detuner with the 1st by the received signal before the whole phase addition of whole addition portion.At this moment, switch the demodulation mistake that produces, can reduce time sidelobe owing to can not produce by the focus section.In addition, detuner that need be identical with Vib. quantity by detuner being configured to 2 sections, being compared with the situation of 1 section formation and can be reduced circuit scale.

The code length of the 1st modulation code sequence can be as equal with the encoded interval of the coding elements that constitutes the 2nd modulation code sequence or below it.At this moment, constitute the coding elements coefficient of synthetic modulation code sequence, can be by each coding elements coefficient of the 2nd modulation code sequence, multiply by the whole coding elements coefficients that constitute the 1st modulation code sequence and obtain.

As the formation of above-mentioned sending part, can have: the code storage portion that stores multiple modulation code sequence coefficient in advance; Select the selection portion of the 1st modulation code sequence and the 2nd modulation code sequence from code storage portion; Respectively with the 1st and the 2nd modulation code sequence coefficient adjustment, synthesize the encoded interval that needs, generate the synthetic portion of synthetic modulation code sequence.At this moment, can freely select the 1st and the 2nd modulation code sequence, make its state that meets the position of making a video recording or user's needs.

In addition, other formations as above-mentioned sending part also can have: the composite coding storage part of storing multiple above-mentioned synthetic modulation code sequence in advance; Select the selection portion of 1 synthetic modulation code sequence from the composite coding storage part.This formation has circuit and constitutes simple advantage.

In addition, the diagnostic ultrasound equipment of other modes of the present invention has: send between object to be detected and receive hyperacoustic probe; Output is used to drive the sending part of the transmission signal of above-mentioned probe; Be used to handle the received signal that above-mentioned probe receives, obtain the acceptance division of the received signal that higher hamonic wave is reinforced; And the image construction portion that uses the hyperacoustic higher hamonic wave picture of receiving signal reconstruction of above-mentioned acceptance division output.Sending part makes, output will generate according to a plurality of modulation code sequences, and the phase pushing figure of corresponding first-harmonic is as the transmission signal of the synthetic modulation code sequence of coding elements value.Acceptance division possesses the detuner of the modulation that demodulation to received signal undertaken by synthetic modulation code sequence.Phase pushing figure by using the first-harmonic that correspondence is such can obtain the received signal that higher hamonic wave is reinforced as the synthetic modulation code of coding elements value.And, because detuner is divided into multistage, both reduced circuit scale, can obtain the effect that secondary lobe reduces again.

Above-mentioned sending part can become by the output expression is as the waveform of the phase pushing figure of the coding elements value of synthetic modulation code sequence successively, and generation sends the formation of signal.

Synthetic modulation code sequence can use the sign indicating number sequence according to the 1st modulation code sequence and the generation of the 2nd modulation code sequence.At this moment, acceptance division can have: the 1st detuner that is used for the modulation that demodulation to received signal undertaken by the 1st modulation code sequence; The 2nd detuner that is used for the modulation that demodulation to received signal undertaken by the 2nd modulation code sequence.Received signal is by after the detuner demodulation of the 1st and the 2nd detuner, again by another detuner demodulation.

The coding elements coefficient of the 1st and the 2nd modulation code sequence is+1 ,-1, during 2 values, phase pushing figure as the coding elements of synthesizing modulation code sequence can be used as, the 1st and above-mentioned the 2nd modulation code key element multiply each other, obtain back-1 the number of times that multiplies each other, the phase pushing figure that changes with the size of number of times.

At this moment, establishing the number of times that strengthen higher hamonic wave is M, when above-mentioned-1 number of times is N, the coding elements of synthetic modulation code sequence, for can by (180 °/M) * phase pushing figure of N decision.

Acceptance division has from the wave filter by removal first-harmonic composition the 1st and the 2nd detuner demodulated received signal.Thus, can remove the first-harmonic composition, further strengthen the higher hamonic wave composition by wave filter.

In addition, sending part can become, and output will be synthesized the phase pushing figure of each coding elements of the waveform signal of modulation code sequence and synthetic modulation code sequence, respectively in a formation of the waveform signal of another synthetic modulation code sequence of phase shift predetermined bits phasor.Acceptance division can become and has, by will be in the transmission signal of 2 synthetic modulation code sequences the received signal of the waveform signal of output at first, synthetic with the received signal of the waveform signal of back output, offset the formation of the synthetic portion of received signal of first-harmonic composition.Thus, by offsetting, remove first-harmonic composition, further higher hamonic wave composition.

For example, the formation as sending part can have:

Storage part, it stores the 1st and the 2nd modulation code sequence; The phasic difference determination section, the 1st and the 2nd modulation code sequence that it receives from above-mentioned storage part, the number of times of counting-1, according to number of times, the phase pushing figure of prior distribution provisions; And the waveform storage part, the corresponding a plurality of waveforms of the phase pushing figure of regulation in advance of its storage, with the waveform of the phase pushing figure of the above-mentioned phasic difference determination section decision of correspondence as sending signal output.In addition, other formations as sending part can have: the composite coding storage part of storing multiple synthetic modulation code sequence in advance; Select the selection portion of 1 synthetic modulation code sequence from above-mentioned composite coding storage part.

Can use than the big interval of the 2nd modulation code sequence encoded interval as the encoded interval of above-mentioned the 1st modulation code sequence.At this moment, the 1st and the 2nd detuner, with will from the received signal of probe output by above-mentioned the 1st detuner demodulation after, dispose by the mode of the 2nd detuner demodulation.Thus, since the big modulation code of at first demodulation encoded interval, the discontinuous processing of being implemented after can reducing, for example switching of focus section, the demodulation mistake that the influence of the switching of numerical aperture or the switching of magnification produces can reduce the time sidelobe that is produced by discontinuous processing.

For example, the 1st detuner can be configured in the position of carrying out demodulation, the 2nd detuner is configured in carried out the position of demodulation process by the received signal after the whole phase addition of whole phase addition portion by the received signal before the whole phase addition of above-mentioned whole phase addition portion.Thus, can reduce by the focus section and switch the demodulation mistake that produces, can reduce time sidelobe.And,, also can reduce circuit scale significantly by the 2nd detuner being configured in the back segment of whole phase addition portion.

In addition, also can all be configured in carry out the position of demodulation process by the received signal after the whole phase addition of whole addition portion with the 2nd detuner the 1st.Because this moment, the 1st and the 2nd detuner also can be each 1, can reduce circuit scale significantly.

In addition, also can be configured in the position to carrying out demodulation respectively with the 2nd detuner with the 1st by the received signal before the whole phase addition of whole addition portion.At this moment, do not switch the demodulation mistake that causes, can reduce time sidelobe owing to can not produce by the focus section.In addition,, compare, can reduce circuit scale with the situation of 1 section formation by detuner being become 2 sections formations.

By the present invention, can realize suppressing the increase of circuit scale, the coding that reduces time sidelobe simultaneously receives transmission.

Description of drawings:

Fig. 1 is the block diagram of the diagnostic ultrasound equipment of the present invention's the 1st embodiment.

Fig. 2 is the block diagram of the sending part 12 among Fig. 1.

Fig. 3 is the key diagram that the synthetic modulation portion coding codeX that is synthesized by the synthetic portion 56 of the coding of Fig. 2 is described.

Fig. 4 is the block diagram of the formation of the 1st detuner 40 of presentation graphs 1 and the 2nd detuner 44.

Fig. 5 is the waveform of code decode1 is conciliate in expression by the waveform of the 1st detuner 40 demodulated received signals of Fig. 4 a key diagram.

Fig. 6 is the waveform of code decode2 is conciliate in expression by the waveform of the 2nd detuner 44 demodulated received signals of Fig. 5 a key diagram.

Fig. 7 (a) is as a comparative example, the figure of the signal waveform when representing with 1 section demodulator filter demodulated received signal of 63 taps, Fig. 7 (b) is as a comparative example, the figure of the signal waveform of expression during by 1 section demodulator filter demodulated received signal of 131 taps, Fig. 7 (c) is illustrated in the formation of the 1st embodiment, the figure of the signal waveform during by 2 sections detuners of 31 taps, 40,44 demodulated received signals.

Fig. 8 (a) is the focus data difference of using before and after expression focus section is switched, become the key diagram of discontinuous processing, Fig. 8 (b) is expression, at the coding elements D of the code1 of the coding codeX of Fig. 3 (a) midway, focus section hand-off process takes place, the key diagram when becoming the demodulation mistake.

Fig. 9 (a) is that coding elements D becomes the demodulation mistake in the presentation graphs 8 (a), and the figure of the time sidelobe that produces in received signal, Fig. 9 (b) are the figures of the signal waveform when representing not produce the demodulation mistake.

Figure 10 is the block diagram of the 1st and the 2nd detuner 40,44 configurations of expression the present invention the 2nd embodiment.

Figure 11 is the block diagram of the 1st and the 2nd detuner 40,44 configurations of expression the present invention the 3rd embodiment.

Figure 12 is the block diagram of formation of the transmission waveform generating unit 24 of expression the present invention the 4th embodiment.

Figure 13 (a) is the block diagram of formation of the sending part 12 of expression the present invention the 5th embodiment, and Figure 13 (b) is the block diagram of the formation of expression signal processing part 46.

Figure 14 is the key diagram that the coding elements of 130 couples of codeX of position phase modulation portion of expression Figure 13 is counted-1 number of times.

Figure 15 is the key diagram of the position phase modulation portion 130 of expression Figure 13 according to the transmission waveform of the codeY of the number of times of codeX generation and codeY.

Figure 16 is the first-harmonic of representing to be stored in advance in the waveform storage part 26 of Figure 13,90 ° mutually of positions, 180 °, the key diagram of 270 ° waveform.

Figure 17 is the block diagram of formation of the sending part 12 of expression the present invention the 6th embodiment.

Figure 18 is the block diagram of formation of the signal processing part of expression the present invention the 6th embodiment.

Figure 19 is the codeY that the position phase modulation portion 130 of expression Figure 17 generates, the codeZ that the 2nd coding generating unit generates, and the key diagram of transmission waveform.

Among the figure: 9-input part, 10-probe, 12-sending part, 13-transmission receives the change-over switch group, 14-acceptance division, 16-image construction portion, 18-display part, 20-control part, 22-timing signal generating unit, 24-transmission waveform generating unit, 26-waveform storage part, 28-transmit amplifier, 32-waveform selection portion, 34-amplifier, 36-A/D converter, 40-the 1 detuner, 42-whole phase addition portion, 44-the 2 detuner, 46-signal processing part, 50,51-code storage portion, 52,53-coding selection portion, the synthetic portion of 56-coding, 60-signal register, 62-the 1 demodulator filter, 64-demodulation code storage portion, 66-coefficient register, 68-signal register, 70-the 2 demodulator filter, 72-demodulation code storage portion, 74-coefficient register, 88-composite coding selection portion, 90-composite coding storage part, 92-circuit (line) storer, 94-combiner circuit, 96-frequency band control filters, 130-position phase modulation portion, 131-the 2 coding generating unit, 140-frequency band control filters.

Embodiment

(the 1st embodiment)

With reference to Fig. 1～Fig. 9, the 1st embodiment of using diagnostic ultrasound equipment of the present invention is described.Present embodiment, Synthetic 2 kind modulation code forms synthetic modulation code, and encoding to receive by this synthetic modulation code sends.

Fig. 1 is the block diagram that the integral body of the diagnostic ultrasound equipment of expression present embodiment constitutes.As shown in Figure 1, diagnostic ultrasound equipment possesses: send the probe 10 that hyperacoustic a plurality of Vib.s constitute by receiving between object to be detected; Sending part 12; Send with delay circuit 11; Send and receive change-over switch group 13; Acceptance division 14; Image construction portion 16; Display part 18; Control part 20; Input part 9.Sending part 12 generates the transmission signal of coding under the control of control part 20.Send with the indication of delay circuit 11 according to control part 20, the transmission signal that generates every stipulated time delayed delivery portion.Send and receive change-over switch group 13 each Vib. transmission transmission signal in the variable openings that control part 20 is set.Send ultrasound wave by the assigned position of each Vib. in object to be detected thus, focusing when scanning and sending.In object to be detected, be reflected or the ultrasound wave of scattering, each Vib. by probe 10 receives, be converted to received signal, be transferred to acceptance division 14 by sending reception change-over switch group 13, when carrying out decoding processing, the whole phase (integerphase) that the focusing when being used to receive is handled is handled and addition is handled.Image construction portion 16 is according to the output signal reconstruct ultrasound wave picture (for example, Type B picture, M type picture) of acceptance division 14.The ultrasound wave of reconstruct looks like to be displayed on the display part 18.The photography conditions that control part 20 reception operating personnel set at input part 9 etc., control sending part 12, transmission receive change-over switch group 13, acceptance division 14, image construction portion 16 each several parts with delay circuit 11, transmission.

Use Fig. 2 that the formation of sending part 12 is described.Sending part 12 possesses: timing signal generating unit 22; Generate the transmission waveform generating unit 24 synthetic modulation code, that generate the waveform of corresponding synthetic modulation code of synthetic at least 2 modulation codes; Amplification generates the transmit amplifier 28 that sends signal by the transmission waveform that sends 24 outputs of waveform generating unit.

Send the synthetic modulation code that waveform generating unit 24 generates a Synthetic 2 modulation code in the present embodiment.Therefore, has coding selection portion 52,53, code storage portion 50,51, the synthetic portion 56 of coding, waveform selection portion 32, and waveform storage part 26.Storing multiple modulation code in the code storage portion 50,51 respectively in advance.Modulation code as storage, for example can adopt, Bark (Barker) sign indicating number, Gray (Golay) sign indicating number, the warble sign indicating number of each code length (coding elements number) of (Chirp) sign indicating number, and the well-known various codings that are used for other coding reception transmission, the multiple codings that require in the middle of these are stored in the code storage portion 50,51 in advance.Being stored in the coding in the code storage portion 50 and being stored in coding in the code storage portion 51, both can be coding of the same race, also can be different types of coding.

Coding selection portion 52,53 is received by control part 20 and to select users to wish 2 modulation codes that use in this is measured, i.e. the 1st modulation code (code1), the indication of the kind of the 2nd modulation code (code2).Wherein, as an example, as shown in Figure 3, as code1, select coding elements count the Barker code of L1=5 (+1 ,+1 ,+1 ,-1 ,+1 coded sequence), as code2, select coding elements number (code length) L2=4 Barker code (+1 ,+1 ,-1 ,+1 coded sequence).The address number of storage code1 in a plurality of modulation codes in the coding selection portion 52 prescribed coding storage parts 50 is indicated to code storage portion 50 in the mode of the signal λ 1 of each coding elements coefficient (+1 or-1) of in accordance with regulations the time interval (being called encoded interval) λ 1 output expression code1.On the other hand, coding selection portion 53 is specified, and is stored in the address of storage code2 in a plurality of modulation codes in the code storage portion 51, to press encoded interval λ 2, repeat the coding elements of code1 and count the mode that the signal of each coding elements coefficient is represented in the inferior output of L1 (L1=5), indication code storage portion 51.Wherein, λ 1 is set at and counts time that L2 value λ 2 * L2 equates with the coding elements that the encoded interval λ 2 of code2 multiply by code2 or greater than its time.

The synthetic portion 56 of coding will be by representing successively from the signal of the coding elements coefficient (+1 or-1) of code storage portion 50 receptions, the signal multiplication of the coding elements coefficient (+1 or-1) that receives from code storage portion 51 successively with expression generates the synthetic modulation code X of a Synthetic 2 modulation code.That is, synthetic modulation code X, as shown in Figure 3, each coding elements coefficient of code1 becomes, by the coding of the full coding elements modulation of code2.The coding elements of synthetic modulation code codeX is counted Lx and is become Lx=L1XL2=20.

(modulation code of synthetic modulation code codeX)

Modulation code coefficient=(the modulation code coefficient of modulation code code1) * (the modulation code coefficient of modulation code code2) of synthetic modulation code codeX

＝{+1×(+1，+1，—1，+1)，

+1×(+1，+1，—1，+1)，

+1×(+1，+1，—1，+1)，

—1×(+1，+1，—1，+1)，

+1×(+1，+1，—1，+1))

＝(+1，+1，—1，+1，+1，+1，—1，+1，+1，+1，—1，+1，—1，—1，+1，—1，+1，+1，—1，+1)

The synthetic portion 56 of coding, the signal of the coding elements coefficient (+1 or-1) of the synthetic modulation code codeX that expression is generated outputs to waveform selection portion 32 in required time at interval successively.In the present embodiment, because the coding elements coefficient of synthetic modulation code codeX is 2 values (+1 or-1), the 2 kind waveforms corresponding with it, promptly first-harmonic shape (0 ° mutually of position) is stored in the waveform storage part 26 in advance with the waveform that moves 180 ° of position phases relative to basic waveform.Waveform selection portion 32, according to the signal that receives successively from the synthetic portion 56 of encoding, judge the coding elements coefficient of codeX, the coding elements coefficient that receives is+1 o'clock, the output of first-harmonic shape is indicated to waveform storage part 26, be at-1 o'clock, the output of moving 180 ° of waveforms of position phase is indicated to waveform storage part 26.Waveform storage part 26, by the waveform of indication is exported successively to transmit amplifier 28, the coefficient of synthetic modulation code codeX is output to transmit amplifier 28 with the simulating signal of the modulation waveform that the position is represented mutually.Transmit amplifier 28 generates the signal (being called the coding drive signal) of the modulation waveform of amplifying expression codeX, outputs to the transmission delay circuit 11 of Fig. 1.

Send with delay circuit 11, by the indication according to control part 20, the retardation delay coding drive signal with corresponding Vib. position generates the coding drive signal, is delivered to and sends reception change-over switch group 13.The transmission reception change-over switch group 13 coding drive signal that retardation is different offers the Vib. by control part 20 appointed positions.Thus, by each Vib. of probe 10, send by the ultrasonic beam after the codeX modulation.Focusing when can realize send by above-mentioned delay this moment.

In object to be detected, be reflected or the ultrasound wave of scattering, be transformed to received signal, receive change-over switch group 13 and be sent to acceptance division 14 by sending by each Vib. of probe 10.Because the ultrasound wave that is sent in the object to be detected is modulated by coding, its reflection wave or scattering wave also all become code modulated ripple in addition, carry out decoding processing by acceptance division 14.

To the formation and the action of acceptance division 14, carry out specific description.Acceptance division 14 as shown in Figure 1, possesses: amplifier 34, A/D converter 36, the 1 detuners 40, whole phase addition portion 42, the 2 detuners 44, signal processing part 46.Amplifier 34, A/D converter 36, and the 1st detuner 40 only dispose the identical quantity of Vib. with probe 10.Amplifier 34 is handled by TGC (Time Gain Compensation), the received signal of amplifying each Vib. respectively, and A/D converter 36 is converted to digital signal with the received signal of simulating.The 1st detuner 40 carries out the demodulation of demodulation by the 1st stage of the coding of code1 generation to each received signal.Whole phase addition portion 42, receive all by the signal after 40 demodulation of the 1st detuner, whole phase addition.The 2nd detuner 44 is 1 in order to handle the received signal that is converged to 1 bundle by whole phase addition processing, to received signal, carries out coding the 2nd stage demodulation that demodulation is produced by code2.

The 1st detuner 40 as shown in Figure 4, possesses: signal register 60, demodulation code storage portion 64, coefficient register 66, the 1 demodulator filters 62.Use Fig. 5 that the demodulation action by these generations is described.Signal keeps being transformed to the received signal (IN1) of digital signal by A/D converter 36 with register 60.Demodulation code storage portion 64 stores in advance, respectively a plurality of decoding and codings (decode1) of the modulation code (code1) of corresponding stored all kinds in the code storage portion 50 of sending part 12.Demodulation code storage portion 64 is according to the indication from control part 20, and the code (decode1) of separating of the kind of the coding that in sending part 12 correspondence is used as code1 outputs to coefficient with register 66.The decode1 that coefficient keeps by 64 outputs of demodulation code storage portion with register 66.The 1st demodulator filter 62, by indication according to control part 20, to remaining on coefficient with the code coefficient of the decode1 in the register 66 with remain on signal and carry out product with the value of the received signal in the register 60 and sue for peace,, obtain signal (OUT1) to the code1 demodulated received signal.And demodulator filter 62 is made of FIR wave filter etc., prepares the wave filter of the number of times that needs in advance.

For example, when code1 is Barker code, matched filtering coefficient about time shaft upset code1 coefficient, the size of coefficient is not 1 the filter factor that do not match, and perhaps is used for by obtaining using as decode1 near the filter factor that deconvolutes of 1 value any one with the code1 convolution algorithm.The 1st demodulator filter 62 is by computing code1 and decode1, and as matched filter, the do not match wave filter and the filtrator that deconvolutes move.Use does not match filter factor during as decode1, and the number of times of decode1 big more (code length is long) can reduce time sidelobe more.Therefore, when using Barker code, prepare to have can computing need time sidelobe level the 1st demodulator filter 62 of decode1 arithmetic capability of number of times (for example 31 times).On the other hand, when code1 was Gray code, the matched filter coefficient after using coefficient with code1 about the time shaft upset was as decode1, and the 1st demodulator filter 62 is as these matched filters that carry out the product summation operation are moved.Therefore, during Gray code, the arithmetic capability that the 1st demodulator filter 62 needs can be can computing and the wave filter of the decode1 of code length (coding elements number) same number, and for example during the Gray code of code length 4,4 times arithmetic capability just enough.Like this according to the kind of the coding that uses as code1 and the kind of decode1, the arithmetic capability difference that the 1st demodulator filter 62 needs.Therefore, as the 1st demodulator filter 62, according to the kind that is stored in the coding in the code storage portion 51 in advance, equipment has the wave filter of the maximum times arithmetic capability that needs.Thus, when which kind of no matter selecting encode, can both pass through 40 demodulation of the 1st detuner as code1.

As mentioned above, by each the 1st detuner 40, the received signal OUT1 of the coding that produces by the big code1 of encoded interval after by demodulation, by by whole phase summitor 42 every the back addition mutually of the delayed bit time delay of difference regulation, bring into 1 received signal together.Focusing when thus, realizing receiving.The received signal that is added also keeps not the state of the coded demodulation that produced by code2.Therefore, the coding that produces by code2 by 44 demodulation of the 2nd detuner.

The 2nd detuner 44 with as shown in Figure 4, be the formation the same with the 1st detuner 40, possess: signal is with register 68, demodulation code storage portion 72, coefficient usefulness register 74 and the 2nd demodulator filter 70.Use Fig. 6 that the decryption processing of being undertaken by the 2nd detuner 44 is described.Storing the decoding and coding (decode2) of the modulation code (code2) of distinguishing all kinds of corresponding stored in code storage portion 51 in the demodulation code storage portion 72 in advance.Demodulation code storage portion 72 according to the indication of control part 20, is exported the decode2 of the code2 of corresponding selection with register 74 to coefficient by sending part 12.Decode2 is kept with register 74 by coefficient thus.The 2nd demodulator filter 70 be by will remaining on signal with the output signal in the whole phase summitor 42 in the register 68, and remain on coefficient demodulation with the multiplication sum operation of the decode2 in the register 74, obtain the received signal (OUT2) after the demodulation.Received signal thus, the coded modulation that demodulation is all is assembled the energy of received signal on time-axis direction, become the short pulse signal of the amplitude of the reflection strength with reflection object to be detected.And, the action of the demodulation process of the 2nd demodulator filter 70, the same with the 1st demodulator filter 62.In addition, as the 2nd demodulator filter 70, has arithmetic capability according to the maximum times of code2 kind needs.

Like this, be demodulated into the received signal in 2 stages, received, carry out signal Processing as required by the regulation of control part 20 indications by signal processing part 46 by acceptance division 14.For example, at least one side of code1 and code2, complementation when coding system of using similar Gray code, the addition received signal that the reception more than 2 times of coding sends of overturning.Thus, obtain having the short pulse signal of amplitude of the reflection strength of reflection object to be detected.More than be the formation and the processing of acceptance division 14.Image construction portion 16 by carrying out the image construction after the signal Processing, constitutes ultrasound wave picture (for example, Type B picture, M type picture), shows in display part 18.

Diagram not in the received signal (OUT2) of Fig. 6 receives in the transmission technology at coding, by demodulation, when being focused at the energy of received signal on the time-axis direction, produces the undesired signal that is called as time sidelobe in the front and back of the signal that should obtain.Diagnostic ultrasound equipment by present embodiment can access, and does not increase circuit scale, can also reduce the 1st effect of time sidelobe.In addition, can also be prevented the 2nd effect of the demodulation mistake of the focus section switching of following dynamic focusing.

At first, use Fig. 7 (a)～Fig. 7 (c) that the 1st effect is described.Fig. 7 (a), Fig. 7 (b) represent as a comparative example, the 2nd detuner 44 that does not use Fig. 1 to constitute, the figure of the waveform of the received signal after the demodulation when only carrying out constituting of total demodulation by the 1st detuner 40.Fig. 7 (a) is to use the wave filter that do not match of number of times (tap number) 63 as the 1st demodulator filter 62 of the 1st detuner 40, is to use the wave filter that do not match of tap number 131 among Fig. 7 (b).And, send the modulation code of signal, use the codeX of code length 20 among Fig. 3 of Barker code of composite coding length 4 and code length 5, that uses in the 1st demodulator filter 62 as a comparative example separates code decode1, modulation code that can demodulation codeX in 1 stage.

Using 63 taps not match in the comparative example of wave filter, the signal magnitude of time sidelobe is about 0.5dB shown in Fig. 7 (a), and the signal magnitude of time sidelobe is bigger.On the other hand, use 131 taps not match in the comparative example of wave filter, shown in Fig. 7 (b), the signal magnitude of time sidelobe is lowered to about 0.02dB.Know by these 2 comparative examples, can suppress the signal level of time sidelobe by the tap number that increases demodulator filter.But, owing to need the computing circuit of exponent number quantity in the demodulator filter, in the comparative example of the demodulator filter that uses 131 taps,, then need 131 * k computing circuit, the circuit scale increase if 10 the Vib. number of popping one's head in is k.

On the other hand, in the formation of the present invention's the 1st embodiment, by using the synthetic modulation code codeX behind synthetic modulation code code2 and the modulation code code1, can be divided into the 1st detuner 40 and 44 two stages of the 2nd detuner carries out demodulation.Therefore, as the 1st and the 2nd demodulator filter 62,70, even use the do not match situation of wave filter of 31 taps respectively, the waveform of the received signal after the demodulation, shown in Fig. 7 (c), the signal magnitude of time sidelobe becomes about 0.03dB, has the reduction effect (inhibition effect) of equal above time sidelobe when Fig. 7 (b).And the computing circuit number is 31 that 31 * k of needing of the 1st demodulator filter 62 and the 2nd demodulator filter 70 need, and the computing circuit number of wave filter is for amounting to (31 * k)+31.Therefore, half the following computing circuit quantity of comparative example (131 * k) to use 131 tap filters obtains reducing equal above time sidelobe effect.Like this, in the present embodiment, on one side the inhibition horizontal dimension of time sidelobe is held in the level that requires, compare when in 1 stage, carrying out total demodulation process, can reduce circuit scale.

The 1st effect is not limited to the situation that modulation code is a Barker code, and the situation of for example using Gray code too.As an example, the code length of modulation code is 64, by 1 section demodulator filter demodulation, needs 64 times matched filter, and needing computing circuit quantity is 64 * k.But, even when using the coding of same-code length 64, if use the modulation code codeX of the coding of composite coding length 8 and code length 8, as demodulator filter 62,70, can use 8 times matched filter respectively, by (8 * k)+8 computing circuits can be realized.Therefore, circuit scale can be reduced near 1/4.

Next, the 2nd effect that the focus section that prevents to follow dynamic focusing is switched the demodulation mistake that causes describes.In the diagnostic ultrasound equipment of present embodiment, in order to improve image resolution ratio, the focusing technology when receiving, well-known dynamic focusing processing capacity are installed in the whole phase addition portion 42.In the dynamic focus technology, a plurality of sampling spots (reflection sources) of setting on the depth direction of object to be detected are grouped in a plurality of focus sections, to each focus section setting general-purpose focus data.Use this focus data,, can assemble the ultrasonic beam when receiving on depth direction in the scope than broad by by whole phase addition portion 42 whole Phase Receiver signals.Focus data switches when changing the focus section at every turn.Specifically, shown in Fig. 8 (a), whole phase addition portion 42 uses focus data A at focus section Fn, and whole Phase Receiver signal in setting-up time T, switches to the focus section Fn+1 that uses focus data B.

In the diagnostic ultrasound equipment that carries out such dynamic focusing processing, adopt coding to receive transmission technology, if be the formation of after whole phase addition, carrying out demodulation,, might carry out the hand-off process of focus section midway for the received signal waveform of 1 coding elements of received signal.For example, if when the modulation of synthetic modulation code codeX as shown in Figure 3 sends waveform, can access the received signal behind the coding shown in Fig. 8 (b).By the coding elements D-2 of the long code1 of encoded interval ..., D ... D+2, and the coding elements of the code2 of these coding elements of corresponding modulating is modulated this received signal.If the received signal waveform at a coding elements D of such coding received signal carries out the switching of focus section midway, preceding half period processing time that belongs to focus section Fn of coding elements D, second half section belongs to the processing time of focus section Fn+1, owing to put in order phase with different focus datas, the received signal waveform of coding elements D becomes discontinuous in time T.Therefore, the demodulation process of coding elements D can not normally be carried out, and the mistake of cause and generation is in the time sidelobe that produces in the signal after the demodulation shown in Fig. 9 (a).Constitute big more this phenomenon that occurs more significantly of code length of the coding elements that becomes the demodulation mistake.

To this, in the present embodiment, front and back in whole phase addition portion 42 dispose the 1st detuner 40 and the 2nd detuner 44, at whole phase addition portion 42 leading portions, the big modulation code code1 of demodulation process encoded interval (time width of coding elements), the little modulation code code2 of back segment demodulation process encoded interval in whole phase addition portion 42.Thus, because before being input to whole phase portion 42, the coding elements demodulation that encoded interval is big finishes, switching the discontinuous processing that produces by the focus section of whole phase time can midway carrying out in the big coding elements of encoded interval.Therefore, can reduce time sidelobe.And, at the coding of the little code2 of encoded interval midway, produces the focus section sometimes and switch, but because to become wrong coding elements number be 1 key element of code2, therefore the time sidelobe that produces is little.

And, in the present embodiment, dispose the 1st detuner 40 and the 2nd detuner 44 by front and back in whole phase addition portion 42, reduction is by the time sidelobe of the discontinuous processing generation of the switching of focus section, discontinuous processing in diagnostic ultrasound equipment, be built in and send the variable openings selection portion medium caliber hand-off process that receives in the change-over switch group 13, because the magnification switchings that the TGC that amplifier 34 carries out handles etc. also produce, when the time sidelobe of consequent demodulation mistake, level was big, can before it, dispose the 1st detuner 40, after it, dispose the 2nd detuner 44.Promptly, can be by front and back in the variable openings selection portion, perhaps, the front and back of amplifier 34 dispose the 1st detuner 40 and the 2nd detuner 44, can reduce the demodulation mistake of the discontinuous generation of reception waveform that causes by the bore hand-off process, perhaps, cause receiving waveform discontinuous and time sidelobe of the demodulation mistake that produces by TGC magnification hand-off process.And, when the leading portion of A/D converter 36 disposes the 1st detuner 40 and the 2nd detuner 44, use the simulating signal detuner.

More than, the 1st embodiment is illustrated, be to constitute but the present invention is not limited to the 1st embodiment.For example, in the 1st embodiment, synthetic modulation code codeX has been described by 2 kinds of modulation code code1, the example that code2 is synthetic, the coding that also can synthesize more than 3 obtains synthetic modulation code.At this moment, the coding elements of modulating the 1st modulation code by the 2nd modulation code in a plurality of modulation codes forms synthetic modulation code, and according to the instruction from control part 20, also the coding elements of the synthetic modulation code that can form according to other modulation code modulation.

In addition, in the 1st embodiment, in 1 stage, put in order the phase addition by whole phase portion 42, the Vib. (output channel) that constitutes probe 10 is divided into a plurality of groups, put in order phase addition received signal by the 1st whole phase addition portion that is configured in each group, and can become output constituting by the 2nd whole whole phase addition of phase addition portion with the 1st whole whole phase addition portions.This technology for example is documented in, and the spy opens in flat 2003-No. 225237 communiques.At this moment, can be respectively at backend configuration the 1st detuner 40 of the 1st whole phase addition portion, at backend configuration the 2nd detuner 44 of the 1st detuner 40.Thus,, the quantity of the 1st detuner 40 can be reduced, circuit scale can be further reduced owing to compare with the formation of Fig. 1.

The coding kind of the 1st and the 2nd modulation code code1 and code2 can be according to the characteristic or the diagnosis content at shooting position, and can be configured in computing circuit number in the camera head etc. and suitably select.It is different types of coding that code1 and code2 also begin.For example, code2 as shown in Figure 3 uses as Barker code in the above description, because this coded sequence is identical with the Gray code of code length 4, also can be used as Gray code and uses.At this moment, because codeX becomes the composite coding of Barker code code1 and Gray code code2, in the 2nd detuner of demodulation code2, as decode2, use is to time shaft upset code2, plays the function of using the demodulator filter that the 2nd demodulator filter 70 uses as Gray code.

And, complementary coding such as Gray needs repetition to receive transmission more than 2 times sometimes, but because the number of times of demodulator filter becomes smaller, when using, can reduce the computing circuit scale of device integral body effectively as coding code1 by the 1st detuner 40 demodulation that need Vib. quantity.On the other hand, because the Barker code or the sign indicating number of warbling can send by 1 reception,, be suitable for the short time shooting from following the characteristics of mobile inspection area information extraction such as blood flow or contrast preparation.By the different a plurality of codings of combination variety, can according to the advantage of each modulation code, distinguish when using as required like this, reduce time sidelobe while can reduce circuit scale according to the characteristic at shooting position.

As mentioned above, in the present embodiment, use by Barker code, Gray code, the synthetic modulation code that general codings such as the sign indicating number of warbling generate, synthetic modulation code is not to make up general coding simply, the above coding of Synthetic 2 has feature of the present invention.That is, be by whole coding elements by a coding, modulate the coding elements separately of other codings, the 1st effect of the foregoing circuit scale that can be reduced simultaneously and reduce the device of the 2nd effect of time sidelobe.

(the 2nd embodiment)

Use Figure 10 that the diagnostic ultrasound equipment of the present invention's the 2nd embodiment is described.The diagnostic ultrasound equipment of the 2nd embodiment is with the configuration of the 1st detuner 40 back segment as whole phase addition portion 42.Formation in addition is the same with the 1st embodiment.

The 1st detuner 40 is configured in the formation of Figure 10 of whole phase addition portion 42 back segments, can not obtain illustrating in the 1st embodiment along with the focus section switch to reduce the 2nd effect of time sidelobe, but can obtain fully reducing on one side separates the time sidelobe of timing, Yi Bian reduce the 1st effect that circuit scale reduces.Like this, by at whole phase addition portion 42 backend configuration the 1st detuner 40, do not need Vib. to each probe 10 to dispose the 1st detuner 40, the 1 detuners 40 as long as 1 identical with the 2nd detuner 44 is just passable, compare with the formation of the 1st embodiment, can further reduce circuit scale.And, by adopting 2 sections formations of the 1st detuner 40 and the 2nd detuner 44, compare with the situation of in the past 1 section formation, can reduce the circuit scale of 1 demodulation machine.For example, the same with Fig. 7 (b), in the comparative example of the detuner of putting in order 1 section formation of phase addition portion 42 backend configuration, need to use 131 tap demodulator filters, but as the 2nd embodiment, adopt 2 sections formations of detuner 40,44, the same with Fig. 7 (c), by 2 sections of 31 taps, can be reduced to time sidelobe and 1 section of 131 tap below the peer-level.Because the computing circuit number of 2 sections of 31 taps is 31 * 2=62, although the computing circuit scale of half approximately when being 1 section of 131 tap can access and reduce equal above time sidelobe.

And, because the 1st and the 2nd detuner 40,44 all is configured in the back segment of whole phase addition portion 42, the the 1st and the 2nd detuner 40,44 whichevers leading portion can, whole phase addition portion 42 backend configuration the 2nd detuner 44 also has no relations at its backend configuration the 1st detuner 40 again.

(the 3rd embodiment)

Use Figure 11 that the diagnostic ultrasound equipment of the present invention's the 3rd embodiment is described.The diagnostic ultrasound equipment of the 3rd embodiment is with the configuration of the 2nd detuner 44 leading portion as whole phase addition portion 42.Formation in addition is the same with the 1st embodiment.

The 2nd detuner 44 and the 1st detuner 40 are configured in simultaneously the formation of Figure 11 of whole addition portion 42 leading portions, owing to before whole phase addition, finish the demodulation of received signal, can access the effect that does not produce the time sidelobe that causes by the demodulation mistake of following the focus section switching that illustrates in the 1st embodiment.On the other hand, owing to need the 2nd detuner 44 of the Vib. quantity of configuration probe 10, the effect that circuit scale reduces and the 1st is compared with the 2nd embodiment and to be reduced, but as in the past, compare when the detuner of 1 section formation is configured in the leading portion of whole phase addition portion 42, can fully obtain its effect.Said, in the comparative example of the detuner of putting in order 1 section formation of phase addition portion 42 leading portions configuration, the same with Fig. 7 (b), owing to need to use 131 tap demodulator filters, if the quantity of Vib. is k, computing circuit quantity then needs 131 * k, but it is,, the same with Fig. 7 (c) by 2 sections formations as Figure 11, by 2 sections of 31 taps, can be reduced to time sidelobe and 1 section of 131 tap below the peer-level.Therefore,, the computing circuit number get final product, although the computing circuit scale of half approximately when being 1 section of 131 tap can access the effect of equal above reduction time sidelobe because being 31 * k * 2=62 * k.

And, because the 1st and the 2nd detuner 40,44 all is configured in the leading portion of whole phase addition portion 42, the 1st and the 2nd detuner 40,44 which leading portion can, at probe 10 backend configuration the 2nd detuner 44, also have no relations at its backend configuration the 1st detuner 40 again.

(the 4th embodiment)

Use Figure 12, the 4th embodiment of using diagnostic ultrasound equipment of the present invention is described.The difference of the formation of Figure 12 and the 1st embodiment is sending waveform generating unit 24 configuration composite coding storage parts 90, to store prior Synthetic 2 kind modulation code code1, a plurality of synthetic modulation code of code2.Composite coding selection portion 88 is selected wherein 1 synthetic modulation code codeX according to the control signal from control part 20.Selecteed codeX is transferred to waveform selection portion 32.On the other hand, the 1st detuner 40, the 2 detuners 44 are selected the corresponding code1 that constitutes the codeX of selection, the decode1 of code2, the control signal of decode2 by control part 20 outputs.Other formations are identical with the 1st embodiment.

By the 4th embodiment, compare with the situation of the 1st embodiment, because becoming, the formation of the synthetic modulation code of generation simplifies, can reduce circuit scale.In addition, by the multiple synthetic modulation code of storage in composite coding storage part 90,, can improve the convenience of operative installations owing to select synthetic modulation code according to the characteristic at shooting position easily.And present embodiment can suitably make up with the 2nd, the 3 embodiment.

(the 5th embodiment)

With reference to Figure 13 (a), Figure 13 (b)～Figure 16, the 5th embodiment of using diagnostic ultrasound equipment of the present invention is described.For the image resolution ratio of the ultrasound wave picture that improves bio-tissue and blood flow picture, carry out radiography echo method (contrast echo method) or tissue harmonic imaging method (HTI) etc.The radiography echo method is object to be detected to be dropped into ultrasonic contrast agents, according to hyperacoustic higher hamonic wave composition (for example, 2 subharmonic, 3 subharmonic) that the microvesicle by the ultrasonic contrast agents that drops into reflects, the technology of reconstruct ultrasound wave picture.The tissue harmonic imaging method is that the sound press that is conceived to be caused by the sound press difference when ultrasound wave carries out the dilatational wave propagation in vivo changes, and ultrasound wave is produced the waveform distortion, according to the technology of being out of shape the harmonic components reconstruct ultrasound wave picture that causes by the waveform that produces.In such radiography echo method and tissue harmonic imaging method, by use strengthening the image capture method of higher hamonic wave composition, according to harmonic components, reconstruct ultrasound wave picture clearly.In the present embodiment, by using the synthetic modulation code technology that illustrates in the 1st～the 4th embodiment, can strengthen the harmonic components of received signal.Below, the situation of 2 subharmonic of strengthening reflected signal is described for example.

The diagnostic ultrasound equipment of present embodiment, shown in Figure 13 (a), be and the basic the same formation of the diagnostic ultrasound equipment of the 1st embodiment, but the synthetic portion 56 of the coding that sends waveform generating unit 24 possesses a phase modulation portion 130, and in waveform storage part 26, store 0 ° in advance, 90 °, 180 ° at least 3 kinds waveform aspects are different with the 1st embodiment.In addition, the signal processing part 46 of acceptance division 14 as Figure 13 (b), passes through at the built-in expectation harmonic frequency range signal that makes, and removes frequency band control filters (for example bandpass filter) 140 this point of other frequency ranges, and is different with the 1st embodiment.Position phase modulation portion 130 to each coding elements of the synthetic the same synthetic modulation code codeX that synthesizes with the 1st embodiment of portion 56 that encodes, is determined the phase pushing figure with respect to first-harmonic, generates the processing of the codeY that is represented by phase pushing figure.According to the phase pushing figure of the coding elements of this dephased codeY, select 3 kinds of waveforms of waveform storage part 26.In addition, the frequency band control filters 140 of signal processing part 46 allows to want harmonic wave (2 subharmonic) frequency of the requirement strengthened, decay, removes first-harmonic.

Action to the synthetic portion 56 of encoding describes.The synthetic portion 56 of coding, at first the same as code2 coefficient and code1 multiplication as shown in figure 14 with the 1st embodiment, generate synthetic modulation code codeX.The coefficient of modulation code X is as follows.

(the modulation code coefficient of synthetic modulation code codeX)

The modulation code coefficient of synthetic modulation code codeX

=(the modulation code coefficient of modulation code code1) * (the modulation code coefficient of modulation code code2)

＝{+1×(+1，+1，—1，+1)，

+1×(+1，+1，—1，+1)，

+1×(+1，+1，—1，+1)，

—1×(+1，+1，—1，+1)，

+1×(+1，+1，—1，+1))

=(+1 ,+1 ,-1 ,+1 ,+1 ,+1 ,-1 ,+1 ,+1 ,+1 ,-1 ,+1 ,-1 ,-1, (one 1) ²,-1 ,+1 ,+1 ,-1 ,+1)

Position phase modulation portion 130, each coding elements for to synthetic modulation code codeX obtains its coding elements, and counting multiply by the total (number of times) of the negative coefficient of the negative coefficient of modulation code code2 coefficient and modulation code code1 coefficient.That is, to the coding elements of each codeX, the multiplication number of times of counting when synthetic " negative polarity (-1) ".For example, the coefficient of code2 is+1, and the coefficient of code1 is+1 o'clock, and the number of times of coding elements that multiply by coefficient+1 of its codeX that obtains is 0.The coefficient of code2 is+1, and the coefficient of code1 is-1 o'clock, and-1 the coding elements of the codeX that is obtained by them obtains owing to multiply by 1 time-1, and its number of times is 1.Code2 is that coefficient is-1, and the coefficient of code1 is-1 o'clock, the codeX that obtains by them+number of times of 1 coding elements, obtain owing to multiply by 2 times-1, its number of times is 2.

Therefore, in Figure 15, each coding elements of the synthetic modulation code codeX of expression, the 1st, the 2 coding elements is a number of times 0.The 3rd coding elements is a number of times 1.The 4th coding elements is a number of times 0.The 15th coding elements owing to multiply by 2 times-1, is number of times 2.

Position phase modulation portion 130, according to the number of times of counting, to each coding elements of synthetic modulation code codeX, decision generates the codeY that is represented by phase pushing figure with respect to the phase pushing figure of first-harmonic.Number of times 0 is distributed first-harmonic, and number of times 1 distributes 90 ° of phase pushing figures, and number of times 2 distributes 180 ° of phase pushing figures.Thus, as shown in figure 15, the 1st, the 2 coding elements of synthetic modulation code codeY is so because number of times is 0 to become 0 °.So the 3rd coding elements is because number of times is 1 to become 90 °.So the 4th coding elements is because number of times is 0 ° of 0 amount of becoming.The same with other coding elements, according to number of times first-harmonic is determined phase pushing figure.To the 15th coding elements, owing to be that number of times 2 becomes 180 °.The phase pushing figure of each coding elements of the synthetic modulation code codeY that obtains like this is as follows.

(the position phase of each coding elements of synthetic modulation code codeY)

{0°，0°，90°，0°，

0°，0°，90°，0°，

0°，0°，90°，0°，

90°，90°，180°，90°，

0°，0°，0°，0°}

As shown in figure 16, waveform storage part 26 is stored 0 ° of first-harmonic, 90 ° of the phase pushing figures corresponding with it, 180 °, 270 ° waveform in advance.Waveform selection portion 32 to the coding elements of each codeY, is selected the waveform output of corresponding its phase pushing figure from waveform storage part 26.

Receive the action that sends about the coding that uses so synthetic modulation code codeY,, describe as an example with dropping into the situation of ultrasonic contrast agents.At first, ultrasonic contrast agents is dropped into object to be detected.And, provide the waveform of synthetic modulation code codeY to send signal to probe 10 by sending part 12.Thus, transmit the coding ultrasonic beam by probe 10.By the coding reflection echo signal of probe 10 receptions by the microvesicle reflection of ultrasonic contrast agents.Because the received signal by probe 10 outputs is modulated with codeY, by the 1st detuner 40 and 44 demodulation of the 2nd detuner, but separating that use this moment is tone coded identical with the 1st embodiment, is code1 and corresponding decode1 and the decode2 of code2 that synthesizes modulation code codeX respectively with formation.That is, in the 1st detuner 40, use decode1 demodulation code1, in the 2nd detuner 44, use decode2 demodulation code2.

According to the number of times that multiplies each other of codeX and-1, the waveform of the codeY of demodulation phase shift obtains the received signal that the 2nd subharmonic is reinforced during as demodulation codex like this.For this received signal,, in signal processing part 46,, further strengthen the 2nd subharmonic composition by frequency control wave filter 140 decay first-harmonics owing in the stage after the demodulation, also comprise first-harmonic.At this moment, owing to strengthen the 2nd subharmonic, when can easily from first-harmonic, separate, can access SN than 2 big subharmonic.Therefore,, constitute the ultrasound wave picture, can improve the image resolution ratio of ultrasound wave picture by image construction portion 16 by according to the 2 subharmonic compositions that obtain.

And, in the present embodiment, in example, illustrated owing to strengthen the situation of 2 subharmonic, according to the number of times of (-1),, move 90 ° of position phases with respect to first-harmonic with each coding elements of synthetic modulation code codeX at every turn, be not limited to 2 subharmonic, also can strengthen the harmonic wave more than 3 times.For example, when strengthening 3 subharmonic, according to number of times, 45 ° mutually of positions when strengthening 4 subharmonic, can be moved according to number of times in each 60 ° mutually of positions of moving at every turn.In a word, strengthen reflection echo signal M subharmonic composition (M: in the time of the integer greater than 2), the number of times of (-1) of each coding elements of synthetic modulation code be N (N: integer), as long as with each coding elements with respect to the first-harmonic phase shift (180 °/M) * N.Simultaneously, use signal processing part 46 frequency band control filters 140 pass through scope, permission M subharmonic composition (M: pass through, and removes the wave filter of other scopes by the frequency range integer greater than 2).

And in the present embodiment, because by 2 synthetic modulation code codeX of coding code1, code2, the number of times of (-1) of coding elements is 2 to the maximum, owing to strengthen 2 subharmonic, phase pushing figure is 180 ° to the maximum., also by 3 codings code1, code2, the synthetic modulation code codeX of code3.When synthesizing codeX by 3 codings, the number of times of (-1) of coding elements is 3 to the maximum, distributes 270 ° of phase pushing figures for number of times 3.At this moment, as Figure 16, as the formation that in advance waveform of 270 ° of phase pushing figures is stored in output in the waveform storage part 26.

And, the same as synthetic modulation code, codeX with the 1st embodiment, can make up various codings, when complementations such as using Gray was coding, the upset coding carried out reception transmission more than 2 times, carries out the processing of addition received signal at signal processing part 46.In addition, about the configuration of detuner 40,44, can adopt the formation of the 2nd or the 3rd embodiment.As the 4th embodiment of Figure 12, also can directly codeY be stored into composite coding storage part 90.

(the 6th embodiment)

With reference to Figure 17～Figure 19, the 6th embodiment of using diagnostic ultrasound equipment of the present invention is described.In the above-described 5th embodiment, because the received signal after demodulation comprises composition substantially, it is the formation of removing it by frequency band control filters 140, but in the present embodiment, carry out 2 codings and receive transmission, by the addition received signal, strengthen the higher hamonic wave composition while offset the first-harmonic composition.

The diagnostic ultrasound equipment of present embodiment, with shown in Figure 17, be and the 5th embodiment formation about the same, but the synthetic portion 56 of coding is except having the position phase modulation portion 130 that generates synthetic modulation code codeY (the 1st synthetic modulation code), also have the only mobile ormal weight of position phase, generate the 2nd coding generating unit 131 of the 2nd synthetic modulation code codeZ each coding elements of the 1st synthetic modulation code codeY.In addition, as shown in figure 18, signal processing part 46 has: frequency band control filters 96; Temporary transient storage is by the line memory 92 of the reflected signal of frequency band control filters 96 outputs; And addition, synthetic by 96 outputs of frequency band control filters reflected signal and by the combiner circuit 94 of the reflected signal of line memory 92 outputs.And, in the present embodiment, send by carrying out receiving for 2 times, 2 received signals of addition, Yi Bian owing to offset the first-harmonic composition, Yi Bian strengthen the higher hamonic wave composition, the basic frequency band control filters 96 that do not need, here, be moving for body by object to be detected, the first-harmonic composition that removal can not be offset disposes.

The position phase modulation portion 130 of the synthetic portion 56 of coding, by the processing that illustrates in the 5th embodiment, with as shown in figure 19 synthetic modulation code codeY as the 1st synthetic modulation code generation.Then, the 2nd coding generating unit 131 generates the 2nd of 180 ° of the position phase shift of each coding elements of the 1st synthetic modulation code codeY is synthesized modulation code codeZ.For example, the position of each coding elements of the position phase of each coding elements of the 1st synthetic modulation code codeY and the 2nd synthetic modulation code codeZ is mutually following.

(the position phase of each coding elements of the 1st synthetic modulation code codeY)

{0°，0°，90°，0°，

0°，0°，90°，0°，

0°，0°，90°，0°，

90°，90°，180°，90°，

0°，0°，0°，0°}

(the position phase of each coding elements of the 2nd synthetic modulation code codeZ)

{180°，180°，270°，180°，

180°，180°，270°，180°，

270°，270°，0°，270°，

180°，180°，270°，180°}

The coding that uses the 1st so synthetic modulation code codeY and the 2nd synthetic modulation code codeZ is received the step that sends to be described.At first, the transmission signal waveform of the 1st synthetic modulation code codeY offers probe 10 from sending part 12, sends the coding ultrasonic beam.Coding reflection echo signal by the reflection of the microvesicle of ultrasonic contrast agents is received by probe 10.Be converted to the coding reflected signal of electric signal by 10 each Vib. of popping one's head in, the same with the 5th embodiment, by acceptance division 14, carry out the demodulation process in 2 stages by decode1, decode2 and handle with whole addition, as the 1st reflected signal to signal processing part 46 outputs.The 1st reflected signal is as illustrating that harmonic wave is reinforced in the 5th embodiment.The 1st reflected signal after frequency band control filters 96, temporarily remains in the line memory 92.Figure 18 (B) expression remains on the waveform of the received signal in the line memory 92.

Below, provide to probe 10 by sending part 12 by the 2nd transmission signal waveform of synthesizing modulation code codeZ, send the coding ultrasonic beams by probe 10.The sweep trace of coding ultrasonic beam is controlled in the mode the same with the sweep trace of the coding reception transmission that is produced by the 1st synthetic modulation code codeY.And reflection echo signal is received by probe 10, and received signal after the demodulation process and whole phase addition in 2 stages that produce by the same decode1, decode2 by with the 1st synthetic modulation code codeY the time, outputs to signal processing part 46.The waveform of received signal is shown in Figure 18 (A).Because this received signal waveform, codeZ carries out 180 ° of phase shifts with respect to codeY, the corresponding received signal waveform (Figure 18 (B)) that is produced by the codeY that remains in the line memory 92, first-harmonic composition upset polarity, the polarity but harmonic components does not overturn.Therefore, by by combiner circuit 94 additions, by the reflected signal of synthetic modulation code codeY generation and the reflected signal that is produced by synthetic modulation code codeZ, offset the first-harmonic composition, harmonic components is added, strengthens (Figure 18 (C)).According to the output of combiner circuit 94, the ultrasound wave picture of reconstruct harmonic components.

According to present embodiment, the position of each coding elements by will synthesizing modulation code codeZ is with respect to 180 ° of position phases of each coding elements displacement of codeY, because the first-harmonic compositional polarity of each reflected signal is overturn, both can suppress the first-harmonic composition by addition.2 subharmonic compositions become the composition that is reinforced by addition because polarity there is not upset.Therefore, because the noise of 2 subharmonic compositions can improve the image resolution ratio of ultrasound wave picture than increasing.In addition, because configuration frequency band control filters 96,, during first-harmonic composition that residual addition can not be offset, can remove it by frequency band control filters 96 even by moving at the body that receives the object to be detected between sending for 2 times.Therefore, for the harmonic wave of wanting to strengthen, which reduction becomes the residual first-harmonic of time sidelobe.

In the present embodiment, illustrated to generate and moved 2 synthetic modulation codes of 180 °, same sweep trace has been carried out 2 codings receive the example that sends that be not limited thereto, the reception that also can carry out more than 3 times sends.At this moment, as the 1st synthetic modulation code, the 2nd synthetic modulation code and the 3rd synthetic modulation code synthesize the modulation code that portion 56 generates per 120 ° of position phase shift by coding.By this 1st～the 3rd synthetic modulation code, same sweep trace is carried out 3 codings receive transmission, the reflected signal of corresponding each the synthetic modulation code of addition is strengthened 3 subharmonic compositions while can offset the first-harmonic composition.

In a word, same sweep trace is repeatedly encoded when receive sending, for the phase relation of each synthetic modulation code becomes, if in the product summation, first-harmonic is offset or when reducing, the relation that harmonic wave increases is as long as move the position phase of synthetic modulation code mutually.For example, same sweep trace is carried out repeatedly A (A: when coding natural number) receives and sends, the synthetic modulation code that the coding of the B time (natural number that B:A is following) uses in receiving and sending, phase shift 360 a °/A in position receives the synthetic modulation code that uses in the transmission with respect to (B-1) inferior coding, as long as just can.In addition, receive the position combination mutually that sends number of times and each synthetic modulation code, can strengthen a plurality of harmonic waves and intermediate frequency by coding.And, also can suitably make up the 1st～the 4th embodiment or its variation.

In addition, in above-mentioned the 6th embodiment,, generate codeY based on this by generation codeX such as Barker code row, the same as synthetic modulation code, codeX with the 1st embodiment, can make up various codings.But when complementary systems such as use Gray encoded, in order to obtain 1 received signal, upset was encoded to carry out receiving more than 2 times and is sent, and need carry out the processing of addition received signal by signal processing part 46.Therefore, when using codeY and codeZ, carry out 2 times with codeY and its upset coding and receive transmission, the addition received signal obtains the received signal of corresponding codeY, and, carry out 2 times with codeZ and upset coding thereof and receive transmission, the addition received signal obtains the received signal of corresponding codeZ, by these codeX of circuit addition of Figure 18, the received signal of Y.Therefore, when asking 2 subharmonic, need carry out 4 times, 3 subharmonic need carry out 6 times and receive transmission.

In addition, about the configuration of detuner 40,44, can adopt the formation of the 2nd or the 3rd embodiment.In addition, also can be as the 4th embodiment of Figure 12, directly with codeY, Z is stored in the composite coding storage part 90.

Claims (10)

1. diagnostic ultrasound equipment is characterized in that having:

Probe, it sends between object to be detected and receives ultrasound wave;

Sending part, its output are used to drive the transmission signal of above-mentioned probe;

Acceptance division, it handles the received signal that above-mentioned probe receives, and obtains the received signal after higher hamonic wave is strengthened; And

Image construction portion, it uses the received signal of above-mentioned acceptance division output, the hyperacoustic higher hamonic wave picture of reconstruct,

Each coding elements of the synthetic modulation code sequence that above-mentioned sending part generates synthesizing the 1st modulation code sequence and the 2nd modulation code sequence distributes the phase pushing figure with respect to first-harmonic to generate and output and the corresponding above-mentioned transmission signal of described synthetic modulation code sequence,

Above-mentioned acceptance division, the modulation that above-mentioned receiving signal demodulation is undertaken by above-mentioned synthetic modulation code sequence.

2. diagnostic ultrasound equipment according to claim 1 is characterized in that,

Above-mentioned sending part by exporting the waveform of expression as the above-mentioned phase pushing figure of the value of the coding elements of above-mentioned synthetic modulation code sequence successively, generates above-mentioned transmission signal.

3. according to claim 1 or 2 described diagnostic ultrasound equipments, it is characterized in that,

Above-mentioned acceptance division has the 1st detuner and the 2nd detuner, the 1st detuner is used for modulation that above-mentioned receiving signal demodulation is undertaken by above-mentioned the 1st modulation code sequence, the 2nd detuner is used for modulation that above-mentioned receiving signal demodulation is undertaken by the 2nd modulation code sequence, the the above-mentioned the 1st and the 2nd detuner constitutes: will from the above-mentioned received signal of above-mentioned probe output by a detuner demodulation after, again by the further demodulation of another detuner.

4. diagnostic ultrasound equipment according to claim 3 is characterized in that,

The coding elements coefficient of the above-mentioned the 1st and the 2nd modulation code sequence is+1 ,-1 this 2 value,

Above-mentioned phase pushing figure with respect to first-harmonic be with the above-mentioned the 1st and above-mentioned the 2nd modulation code key element multiply each other, with the phase pushing figure of the corresponding size of back-1 number of times that multiplies each other.

5. diagnostic ultrasound equipment according to claim 4 is characterized in that,

At the number of times of establishing the higher hamonic wave that strengthen is M, when above-mentioned-1 number of times is N, above-mentioned phase pushing figure with respect to first-harmonic by (180 °/M) * the N decision.

6. according to each the described diagnostic ultrasound equipment in the claim 3, its feature exists,

Above-mentioned acceptance division has wave filter, and this wave filter is from being removed the first-harmonic composition the received signal after the above-mentioned the 1st and the 2nd detuner demodulation.

7. diagnostic ultrasound equipment according to claim 1 is characterized in that,

Above-mentioned sending part is except generating and sending the above-mentioned transmission signal corresponding with above-mentioned synthetic modulation code sequence, also generate and send and each coding elements of above-mentioned synthetic modulation code sequence is distributed the corresponding above-mentioned transmission signal of synthetic modulation code sequence that generates with respect to the phase pushing figure of first-harmonic

Above-mentioned acceptance division has the synthetic portion of received signal, the synthetic portion of this received signal offsets the first-harmonic composition by with at first the received signal of the waveform signal of output is synthetic with the received signal of the waveform signal of exporting then in the transmission signal of above-mentioned 2 synthetic modulation code sequences.

8. diagnostic ultrasound equipment according to claim 4 is characterized in that,

Above-mentioned sending part has:

Storage part, it stores the above-mentioned the 1st and the 2nd modulation code sequence;

The phasic difference determination section, it receives the 1st and the 2nd modulation code sequence and counts-1 number of times from above-mentioned storage part, distributes the phase pushing figure of regulation in advance according to above-mentioned number of times; And

The waveform storage part, it is stored and the corresponding a plurality of waveforms of stipulating in advance of phase pushing figure, will export as sending signal with the corresponding waveform of phase pushing figure that above-mentioned phasic difference determination section is determined.

9. diagnostic ultrasound equipment according to claim 1 is characterized in that,

Above-mentioned sending part has:

The composite coding storage part, it stores multiple above-mentioned synthetic modulation code sequence in advance;

Selection portion, it selects 1 synthetic modulation code sequence from above-mentioned composite coding storage part.

10. diagnostic ultrasound equipment according to claim 3 is characterized in that,

The encoded interval of above-mentioned the 1st modulation code sequence is bigger than the encoded interval of the 2nd modulation code sequence,

The the above-mentioned the 1st and the 2nd detuner is, after the received signal of above-mentioned the 1st detuner demodulation by above-mentioned probe output, by constituting of above-mentioned the 2nd detuner demodulation.

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