JP2013090839A - Ultrasonic diagnostic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute power-saving control in an ultrasonic diagnostic apparatus equipped with a battery.SOLUTION: Buffer circuits 14, 30, 34, 40, and 44 are provided on former stages or subsequent stages of processor circuits 18, 32, and 42. Each buffer circuit has a plurality of memory elements 16 set parallel. Each processor circuit has a plurality of memory devices 22 and 24. When a data transfer rate is lowered due to change of conditions for transmission/reception, for example, decline of a frame rate, the number of memory elements used in each buffer circuit is reduced, and in other words, the number of unused memory elements is increased. As a result, power saving is carried out in each buffer circuit, and the number of memory devices used in each processor circuit is applicably reduced.

Description

  The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to power saving control of an ultrasonic diagnostic apparatus including a plurality of processors.

  The ultrasonic diagnostic apparatus includes a plurality of processors that perform signal processing in stages. For example, a processor that generates quadrature beam data by applying quadrature detection to RF beam data, a B-mode processor that applies processing for forming a B-mode image to complex beam data, and two processors for complex beam data. A color flow processor for applying a process for forming a three-dimensional blood flow image is provided. Each processor includes an input / output unit, a calculation unit, a storage unit, and the like, and executes data processing according to a program.

  The load dynamically changes in each processor, that is, the processing speed of input data dynamically changes at each time point. As a result, a processing time difference occurs between the processors, so that a buffer circuit for temporarily storing data is provided between the processors and before and after the processor row. Each buffer circuit is usually composed of a plurality of FIFO memories (chips) provided in parallel. This is because the writing target and the reading target are alternately set so that writing and reading are not simultaneously performed on the same FIFO memory. If the time difference becomes large or the amount of transferred data increases, if there is a possibility that overflow will occur just by performing ping-pong control with two FIFO memories, for example, three or four FIFO memories are provided per buffer circuit. It is done. Each FIFO memory normally has a storage capacity for one beam data, and the writing target is varied in units of beams.

  Various techniques have been proposed for realizing power saving in an ultrasonic diagnostic apparatus. Patent Document 1 discloses an ultrasonic diagnostic apparatus that suppresses wasteful power consumption by performing control such as power-off of individual circuits, clock rate down, clock-off, and change to a sleep mode according to an operation mode. ing. The configuration disclosed as an embodiment of Patent Document 1 performs control such as power-off in large functional units (large block units) such as a transmission unit and a reception unit. Even when the same B mode is selected, the data transfer rate varies greatly depending on the beam scanning conditions, but detailed power saving control according to such a data transfer rate is not disclosed.

  Recently, a small-sized ultrasonic diagnostic apparatus equipped with a battery and driven by the battery has been put into practical use. In such an ultrasonic diagnostic apparatus, it is particularly necessary to suppress battery consumption. For example, it is conceivable to execute control to reduce the number of transmissions per unit time when the battery is exhausted. Patent Document 2 discloses an ultrasonic diagnostic apparatus that changes an operation mode in accordance with the remaining power.

JP 2000-70262 A JP 2010-167083 A

  The ultrasonic diagnostic apparatus is provided with a plurality of buffer circuits. Each buffer circuit includes a plurality of memories already described, and these are selectively used. However, even if there is a surplus in the prior art, all the memories are in an operable state, that is, power is supplied to all of them.

  An object of the present invention is to enable finer control for power saving in an ultrasonic diagnostic apparatus.

  An ultrasonic diagnostic apparatus according to the present invention is provided with a plurality of processors that process data obtained by transmission and reception of ultrasonic waves in stages, and at a front stage, an intermediate stage, or a rear stage of the plurality of processors. At least one buffer circuit that stores data and a control unit that controls the operation of the buffer circuit, the buffer circuit including a plurality of buffer memory elements provided in parallel, and writing to the same buffer memory element In addition, the beam data writing target and the beam data reading target are switched and selected from the plurality of buffer storage elements so that the reading does not occur at the same time, and the control unit is responsive to the data transfer rate depending on the ultrasonic transmission / reception conditions. The first power saving control for changing the number of used elements actually used among the plurality of buffer storage elements is implemented. To. Preferably, the control unit cuts off power supply to unused elements that are not actually used among the plurality of storage elements in the first power saving control.

  According to the above configuration, in the first power saving control, the number of elements that are actually used is limited among the plurality of buffer storage elements (preferably FIFO memory chips) included in the buffer circuit. Power saving corresponding to the number can be achieved. For example, the clock supply to the unused elements is stopped or the power supply is stopped. It is desirable to employ at least the latter, if necessary, both. Recently, a design for configuring an ultrasonic diagnostic apparatus using a processor as a basic unit is being performed. In that case, it is necessary to provide a buffer circuit in front of the processor or between the processors. It is necessary to provide it. In this case, for example, if power supply to resources not used in each buffer circuit is stopped, a large power saving result can be obtained for the entire apparatus. In particular, in an ultrasonic diagnostic apparatus that incorporates and is driven by a battery, there is a strong demand for power saving to prevent the battery from being consumed. Therefore, it is desirable to employ the above-described configuration in such an apparatus.

  The power saving control described above is executed in response to changes in transmission / reception conditions such as a decrease in frame rate, and more preferably adaptively according to the actual or calculated data transfer rate. Is done. For example, when the data transfer rate is lowered step by step, it is desirable to reduce the number of used elements step by step accordingly.

  Preferably, a plurality of buffer circuits are provided corresponding to the plurality of processors, each of the buffer circuits includes a plurality of buffer storage elements provided in parallel, and the control unit is responsive to the data transfer rate. Then, the first power saving control is executed for each buffer circuit.

  Preferably, each of the processors includes a plurality of internal storage elements, and the control unit uses elements that are actually used from the plurality of internal storage elements in accordance with the data transfer rate together with the first power saving control. And the second power saving control is executed to cut off the power supply to the unused elements that are not actually used from the plurality of internal storage elements. According to this configuration, a large power saving result can be obtained by a combination of the first power saving control and the second power saving control. Preferably, the ultrasonic diagnostic apparatus is a portable apparatus that includes a battery and operates with electric power from the battery.

  Even if the amount of power supply to the elements such as the memory element and the memory is small, the power supply amount is appropriate for the whole of a large number of elements. Therefore, it is beneficial for extending the battery life to stop unnecessary storage device operations in conjunction with power saving control such as transmission power reduction.

  According to the present invention, it is possible to perform finer control for power saving in the ultrasonic diagnostic apparatus.

1 is a block diagram showing a preferred embodiment of an ultrasonic diagnostic apparatus according to the present invention. It is a conceptual diagram for demonstrating the power saving control based on monitoring of a battery remaining charge. It is explanatory drawing which shows the item performed in general power saving control. It is a figure for demonstrating switching control of the number of memory elements to be used.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.

  FIG. 1 shows a preferred embodiment of an ultrasonic diagnostic apparatus according to the present invention, and FIG. 1 is a block diagram showing the configuration of the main part thereof. This ultrasonic diagnostic apparatus is used in the medical field, and forms an ultrasonic image showing the structure of a living body by transmitting and receiving ultrasonic waves to and from the living body. The ultrasonic diagnostic apparatus shown in FIG. 1 includes a battery and operates with electric power supplied from the battery. That is, this ultrasonic diagnostic apparatus is a small and portable apparatus. However, the present invention can also be applied to other general ultrasonic diagnostic apparatuses.

  In FIG. 1, the code | symbol 10 has shown the battery, and electric power is supplied with respect to each structure shown by FIG. 1 from the battery. However, each component may operate based on the supply of commercial power. Ultrasound is transmitted and received by a probe (transmitter / receiver) not shown. Specifically, a 1D array transducer is provided in the probe, thereby forming an ultrasonic beam electronically and scanning it electronically. As the electronic scanning method, an electronic sector scanning method, an electronic linear scanning method, and the like are known. A transmission beamformer is connected to the probe, and a reception beamformer 12 is connected to the probe. Here, the reception beamformer 12 is a digital beamformer in the present embodiment.

  That is, the reception beamformer 12 performs phasing addition processing on a plurality of reception signals, thereby generating a reception signal after phasing addition, that is, beam data. Each beam data corresponds to one ultrasonic beam, which consists of a plurality of echo data arranged in time series. As shown in FIG. 1, the beam data output from the beamformer 12 is sent to the processor circuit 18 via the buffer circuit 14.

  The processor circuit (processor unit) 18 is a circuit that performs, for example, quadrature detection processing, and performs quadrature detection processing on beam data as an RF signal, and as a result, generates a digital complex signal.

  A buffer circuit 14 is provided in the preceding stage to provide input data in accordance with the processing speed in the processor circuit 18. As illustrated, the buffer circuit 14 includes a plurality of memories (FIFO memories) 16 provided in parallel. The memory 16 constitutes a storage element, that is, a device (or chip), and writing or reading is performed with this as a unit. The plurality of storage elements 16 are provided in parallel to prevent the writing target and the reading target from being the same element. Usually, the writing target and the reading target are separate elements, and It can be switched with rotation. This is also called ping-pong control. In the illustrated example, four storage elements 16 are provided in parallel. This is because the necessary data amount is buffered in accordance with the processing speed in the processor circuit 18. A switch circuit S1 is provided in the previous stage of the plurality of storage elements 16, and a switch circuit S2 is provided in the subsequent stage. The switch circuit S1 selects the memory element 16 to be written, and the switch circuit S2 selects the memory element 16 to be read. However, in practice, the switch circuits S1 and S2 may be realized as functions of the processor 20, and switching between them may be realized as functions of the CPU 48 described later.

  In the example shown in the drawing, the processor circuit 18 includes a processor 20 constituting an arithmetic unit and a plurality of storage units (memory) 22 and 24 connected in parallel to the processor 20. In the illustrated example, two memories are provided. Of course, three or more memories may be provided. The illustrated memory corresponds to a unit for turning on / off the power supply. The same applies to the memory element 16 described above.

  A B-mode processing system 26 and a Doppler information processing system 28 are provided in parallel at the subsequent stage of the processor circuit 18 that performs the quadrature detection processing. Furthermore, other processing systems may be provided in parallel.

  The B mode processing system 26 includes a buffer circuit 30, a processor circuit 32, a buffer circuit 34, and a DMA controller 36. Specifically, the buffer circuit 30 and the buffer circuit 34 have the same configuration as the buffer circuit 14 described above. Of course, the number of memory elements required in each of the buffer circuits 30 and 34 may be varied. The buffer circuit 30 is provided as a buffer memory in order to absorb the difference in processing speed between the processor circuit 18 and the processor circuit 32. Similarly, the buffer circuit 34 is provided to absorb a speed difference between the processor circuit 32 and the DMA controller 36.

The processor circuit 32 has the same configuration as the processor circuit 18 described above, that is, includes a processor 20 and two storage units 22 and 24. The processor circuit 32 is a part that executes signal processing for forming a B-mode image. For example, logarithmic compression, noise removal,
Signal processing such as contrast adjustment and gain adjustment is executed. The DMA controller (DMAC) 36 is a controller for transferring blocks of data from the processor circuit 32 to the CPU 48. Actually, data is transferred from the buffer circuit 34 to the CPU 48. In that case, a general-purpose parallel bus 38 is used.

  The Doppler information processing system 28 will be described. The processing system 28 includes a buffer circuit 40, a processor circuit 42, a buffer circuit 44 and a DMA controller 46. The buffer circuit 40 and the buffer circuit 44 have the same configuration as that of the buffer circuits 14, 30, and 34 described above, that is, a plurality of storage elements 16 and switch circuits S1 and S2. The processor circuit 42 has the same configuration as the processor circuits 18 and 32 described above, that is, includes a processor 20 and two storage units 22 and 24. However, the buffer circuits 40 and 44 and the processor circuit 42 may have a configuration different from the configuration described above.

  The processor circuit 42 executes processing for extracting Doppler information. For example, a circuit that performs an autocorrelation calculation or the like may be used. Each processor circuit is constituted by a digital signal processor or the like. That is, they are programmed. Data generated after processing the Doppler information is transferred from the buffer circuit 44 to the CPU 48 via the DMA controller 46 and the bus 38.

  The CPU 48 performs overall control of the ultrasonic diagnostic apparatus and executes necessary data processing. In the present embodiment, the CPU 48 has a function as a digital scan converter and also functions as a power saving control unit. A storage unit 50 connected to the CPU 48 stores a program for controlling the entire apparatus, a scan conversion program, a power saving program, and the like. A processor for display processing, a processor for storage processing, and the like are connected to the bus 38. In the present embodiment, a necessary ultrasonic image is generated by the CPU 48 and necessary display processing is executed, and then image data is sent to the display unit.

  In each processor circuit, the necessary number of storage elements are provided in parallel in each buffer circuit so that each process proceeds smoothly even when the maximum processing speed is exhibited and the data transfer rate is maximum at the same time. It has been. In the present embodiment, for example, four storage elements are provided in parallel in each of the buffer circuits 14, 30, 34, 40, and 44, and are selectively used while being switched. However, as will be described below, when the frame rate is lowered and the data transfer rate is also lowered in the power saving control, a storage element that is redundant or not necessarily used is generated in the buffer circuit. Similarly, in each processor circuit, a memory or the like that does not actually need to be used among a plurality of storage units or memories included in the processor circuit may be generated. In the ultrasonic diagnostic apparatus of the present embodiment, power supply to such devices that do not need to be used is stopped, thereby achieving power saving. Of course, in that case, the supply of clocks or the like may be stopped.

  First, general power saving control will be described with reference to FIGS. As shown in the conceptual diagram in FIG. 2, the remaining amount of the battery is constantly monitored (S10), and if the remaining amount is appropriate, the operating condition for full operation is set (S12). On the other hand, if a shortage is detected and it is about 1 (S14), the first mode is executed as power saving control (S16). Accordingly, when the remaining amount is insufficient and the degree 2 is determined (S18), the second mode is implemented as the power saving control (S20). Further, when the remaining amount is insufficient, that is, when the remaining level is about 3 (S22), the third mode is implemented as power saving control (S24). Then, the degree or strength of the power saving control is switched in stages depending on the magnitude of the remaining amount.

  In FIG. 3, items to be executed in the power saving control are displayed as a list 52. The list 52 includes transmission power down, frame rate reduction, manual trigger transmission or electrocardiographic trigger transmission, operation mode limitation, luminance limitation, and the like. In any case, the frame rate is generally reduced, and such control results in a lower data transfer rate in the received signal processing system. Of course, a reduction in data transfer rate also occurs when trigger transmission or operation mode restriction is performed.

  Therefore, in this embodiment, as shown as a table 54 in FIG. 4, the number of storage elements (FIFO chips) to be used is stepwise according to the data transfer rate, in other words, according to the frame rate (see reference numeral 56). (See reference numeral 58). At the same time, in the processor circuit, the number of memories to be used is switched in stages (see reference numeral 60). In the illustrated example, the number of used chips is switched in stages such as 4, 3, 2, 1, 0 in accordance with the transmission rate. Here, when the number of chips used is 2, typical ping-pong control is executed. When the transmission rate becomes extremely low, the number of chips used is 1, that is, writing and reading are performed on the same chip. That is, the amount of data per unit time is small enough to allow such control. In the frozen state, the number of chips used is zero. In the present embodiment, the memory connected to the CPU functions as a cine memory, that is, a large amount of beam data is stored therein. Therefore, in the frozen state, that is, in the state where transmission / reception is stopped, the configuration before each processing system 26, 28 shown in FIG. 1 is not used, and therefore no power is supplied to any chip in each buffer circuit. It will be. Thereby, significant power saving can be achieved.

  In the present embodiment, the number of used memories is reduced stepwise according to the transmission rate. Thereby, power saving can be achieved not only in the buffer circuit but also in the processor circuit. By combining such power saving control of stopping the operation in units of storage devices or storage chips, a large power saving can be achieved for the entire apparatus.

  The CPU 48 shown in FIG. 1 implements the control as described above, and the CPU 48 provides control signals 100 and 102 to each circuit via the bus 38. Here, the control signal 100 is a control signal given to each buffer circuit, and the control signal 102 is a control signal given to each processor circuit. The control content given to each circuit may be the same or different.

DESCRIPTION OF SYMBOLS 10 Battery, 12 Digital beam former (DBF), 14, 30, 34, 40, 44 Buffer circuit, 16 Memory element (FIFO memory), 18, 32, 42 Processor circuit.

Claims (5)

A plurality of processors that process data obtained by ultrasonic transmission and reception in stages;
At least one buffer circuit that is provided upstream, intermediate, or downstream of the plurality of processors and that temporarily stores beam data;
A control unit for controlling the operation of the buffer circuit;
Including
The buffer circuit includes a plurality of buffer storage elements provided in parallel, and a beam data write target and a beam data read from the plurality of buffer storage elements so that writing and reading to the same buffer storage element do not occur simultaneously. The target is switched and selected.
The control unit executes first power saving control for changing the number of used elements actually used among the plurality of buffer storage elements in accordance with a data transfer rate depending on an ultrasonic transmission / reception condition. A characteristic ultrasonic diagnostic apparatus. The apparatus of claim 1.
The ultrasonic diagnostic apparatus, wherein the control unit cuts off power supply to an unused element that is not actually used among the plurality of buffer storage elements in the first power saving control. The apparatus of claim 1.
A plurality of buffer circuits are provided corresponding to the plurality of processors,
Each of the buffer circuits includes a plurality of buffer storage elements provided in parallel,
The control unit executes the first power saving control on the buffer circuits according to the data transfer rate.
An ultrasonic diagnostic apparatus. The device according to any one of claims 1 to 3,
Each processor includes a plurality of internal storage elements;
The control unit, along with the first power saving control, varies the number of used elements actually used in the plurality of internal storage elements according to the data transfer rate, and among the plurality of internal storage elements. Execute second power saving control to cut off power supply to unused elements that are not actually used.
An ultrasonic diagnostic apparatus. The apparatus according to any one of claims 1 to 4,
The ultrasonic diagnostic apparatus is a portable apparatus that includes a battery and operates with electric power from the battery.

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