CN201312811Y - High Frequency Ring Array Digital Ultrasound System - Google Patents

Abstract

The utility model belongs to the technical field of ultrasonic detection, in particular to a high-frequency ring array digitized ultrasonic system. In order to overcome the shortcomings of linear array and other scanning technologies that can only focus in one dimension, improve the resolution in all directions, effectively improve the signal-to-noise ratio, and maximize the image quality, the technical solution adopted by the utility model is: including: sequentially connected rings Array transducer, receiving system, analog-to-digital converter, receiving dynamic focusing and variable aperture control beamforming module, digital echo synthesis module, ultrasonic signal processing module, display unit, and also includes a processor, which sequentially controls the The system and the ultrasonic emission drive system are connected with the ring array transducer, and the processor is also respectively connected with the analog-to-digital converter, the receiving dynamic focus and the variable aperture control beam forming module. The utility model is mainly used in the design and manufacture of ultrasonic testing instruments.

Description

High Frequency Ring Array Digital Ultrasound System

technical field

The utility model belongs to the technical field of ultrasonic detection and a detection instrument, in particular to a high-frequency ring array digitized ultrasonic system.

Background technique

In the currently commonly used B-type ultrasonic diagnostic instruments, single-chip transducers and linear array transducers are mainly used, and the lateral resolution is several times worse than the axial resolution, which will affect the detection of small lesions. The focus of the single-chip transducer is determined, and it only has a higher resolution in the focal area; the linear array transducer uses electronic focusing, which can obtain a synthetic field of view from a short distance to a long distance, but can only obtain a one-dimensional sound beam cross section. focus effect.

Utility model content

In order to overcome the deficiencies of the prior art, the purpose of this utility model is to: overcome the shortcomings of linear array and other scanning technologies that can only focus in one dimension, improve the resolution in all directions, effectively improve the signal-to-noise ratio, and maximize the image quality.

In order to achieve the above purpose, the technical solution adopted by the utility model is a high-frequency ring array digital ultrasonic system, including: a ring array transducer connected in sequence, a receiving system, an analog-to-digital converter, receiving dynamic focusing and variable aperture control beam The forming module, the digital echo synthesis module, the ultrasonic signal processing module, the display unit, and the processor are also included. The processor is connected with the ring array transducer through the timing control system and the ultrasonic emission drive system in turn, and the processor is also connected with the module The converter, the receiving dynamic focus and the variable aperture control beamforming module are connected.

The ring array transducer is a five-ring high-frequency ring array transducer with a center frequency of 10MHz. It is composed of a group of concentric multi-element crystals. Each crystal is independently connected to the ultrasonic transmitting/receiving drive system. The ring radius of the transducer is From the outermost ring to the center ring are: 3.60mm, 3.22mm, 2.97mm, 2.28mm, 1.61mm, and the area of each ring of the five-ring transducer remains equal.

The analog-to-digital converter is a single-chip 8-channel ultrasonic receiver, the model is AD9271.

The structure of the ultrasonic transmission drive system is: the pulse signal voltage output by the FPGA chip is converted into two outputs through the voltage conversion chip, one output is connected to the gate of the field effect transistor through a capacitor, and the other output is connected to the gate of another field effect transistor, connected to The drain of the field effect transistor of the capacitor is connected to the power supply, the source thereof is connected to the drain of another field effect transistor and used as an emission output terminal, and the source of the other field effect transistor is grounded.

The receiving dynamic focus and variable aperture control beamforming module, the digital echo synthesis module, the ultrasonic signal processing module and the processor are integrated in a field programmable gate array FPGA.

The utility model has the following technical effects:

The high-frequency circular array water bath rotary ultrasonic probe provided by the utility model, and the corresponding transmitting and receiving circuits, carry out digital signal processing after digital processing by AD9271, realize two-dimensional full-range dynamic focusing, and improve the resolution in all directions. The use of digital imaging technology can effectively Improve the signal-to-noise ratio, maximize the image quality, and increase the detection rate of early breast masses.

Description of drawings

Figure 1 is a structural diagram of the high-frequency ring array detection system.

Figure 2 is a cross-sectional view of the ring array probe.

Figure 3 is a schematic diagram of the transmitter circuit.

Figure 4 is a waveform diagram of the excitation pulse signal.

Figure 5 is a schematic diagram of the receiving circuit.

Detailed ways

The structural block diagram of the high-frequency ring array ultrasonic detection system is shown in Figure 1. The high-frequency ultrasonic detection system controls the ultrasonic probe transmitting/receiving circuit by the microprocessor, and detects the mammary gland through the ring array water bath probe. After a series of digital signal processing, a video signal display is formed. The digital imaging technology can effectively improve the signal-to-noise ratio and maximize the image quality. A high-frequency ring array digitized ultrasonic system includes a probe, a transmitting/receiving circuit of the probe, an A/D conversion circuit, and a signal control and processing circuit.

Probe:

The ring array transducer is composed of a group of concentric multi-element crystals. Each crystal is excited by a pulse signal. Through electronic focusing, the beam is focused along the axial direction to become a very precise point. By adjusting the pulse delay, continuous Dynamic focusing, while adopting the method of variable aperture, as the scanning depth increases, the effective aperture gradually increases, and the depth of synthetic field of view of the ring array is increased, thereby improving the lateral resolution of the entire imaging depth and realizing two-dimensional full-range Dynamic focus.

According to the research needs, the probe is designed with a five-ring high-frequency ring array transducer with a center frequency of 10MHz. The ring radii of the transducer from the outermost ring to the center ring are: 3.60mm, 3.22mm, 2.97mm, 2.28mm, 1.61mm , the area of each ring of the five-ring transducer is kept equal, and the cross-sectional view is shown in Figure 2. Considering that the higher the ultrasonic frequency, the faster the attenuation in the tissue, the tissue detection depth we selected is 0-50mm. The ultrasonic frequency is 10MHz, the detection depth is 50mm, the axial resolution is 150 microns, and the lateral resolution is 200 microns, which meets the needs of ultrasonic testing and can effectively improve the detection rate of early diseases. At the same time, digital imaging technology can effectively improve the signal-to-noise ratio and maximize to improve image quality.

Transmit/receive circuit:

The ultrasonic transmission drive system, namely the ultrasonic transmission circuit, is a key part of the pulse echo ultrasonic diagnostic equipment, which is mainly used to generate high-voltage narrow pulse signals to excite the ultrasonic transducer to emit ultrasonic waves. The amplitude and width of the emission pulse are two important indicators. Usually, the larger the amplitude, the stronger the ultrasonic power and the higher the receiving sensitivity; the narrower the pulse width, the higher the resolution and the smaller the blind area. The excitation pulse signal of the low-voltage adjustable pulse width of the circuit is provided by the FPGA chip EP2C35672C6. Since the I/O port voltage of the FPGA chip is 3.3V, the voltage conversion chip can be used to boost the pulse signal voltage and output it, so that the corresponding FET conduction pass, thereby stimulating the transmission of the transducer. The schematic diagram of the transmitting circuit is shown in Figure 3. The pulse signal DINA output by the FPGA chip is output to the IN-A and IN-B input terminals of the voltage conversion chip, the PD and GND terminals of the voltage conversion chip are grounded, the VDD terminal is connected to 5v, VH The terminal is connected to 12V, the output terminal OA is connected to the gate of the field effect transistor Q1 through the capacitor C2, the resistor R1 determines the operating voltage of Q1, and Q1 is connected to the drain of the field effect transistor Q2 through the parallel connected diode D1 and resistor R9, and the gate of Q2 is connected to the voltage On the OB side of the conversion chip, the source of Q2 is grounded, and the source of Q1 is output through the reverse parallel diodes D9 and D10. The DC component of the pulse output is short-circuited to the ground by the inductor L1, and the pulse output is through the resistor R10 and The impedance matching resistor R11 is output, and the capacitors C1, C3, C4, C5, C41, C42, and C301 are power filter capacitors.

The receiving system circuit is shown in Figure 5, including diodes D60, D61, D62, and D63, and resistors R212, R213, and R230. The signal from the transducer is connected to the input terminal between the serially connected diodes D60 and D61, and finally passed through the capacitor C209 is connected to the analog-to-digital converter AD9271, the Q3s device is MMBD4148se, which is a diode packaged in two different directions, sot23 package, resistors R95, R96, R97, R109, capacitors C171, C172, C175, C176, and C215 are AD9271 peripheral devices .

The excitation pulse signal is generated by the FPGA chip EP2C35672C6, and finally the excitation pulse signal of the probe amplified by the FET is shown in Figure 4.

The receiving circuit is shown in Figure 5, and the echo signal is directly A/D converted after being isolated by diodes. The control signal is generated by FPGA chip EP2C35672C6.

The receiving dynamic focusing and variable aperture control beamforming module, the digital echo synthesis module, the ultrasonic signal processing module and the processor are integrated in the aforementioned FPGA chip EP2C35672C6.

A/D conversion circuit:

In traditional all-digital ultrasound instruments, the amplifier circuit and the A/D conversion circuit are integrated on different chips. This technology of discretely forming the echo signal path with multiple chips is very mature and has been adopted by many manufacturers. However, the use of this solution in multi-channel ultrasonic instruments inevitably results in a large number of echo channel chips, a large area occupied by the circuit board, and high power consumption, resulting in a large volume of the instrument, which cannot meet the current development of ultrasonic instruments in the direction of low power consumption and portability. requirements. In an all-digital ultrasonic instrument, the received ultrasonic echo analog signal must be amplified and A/D converted into a digital echo signal for later digital signal processing. In order to solve the above problems, this design adopts the single-chip 8-channel ultrasonic receiver - AD9271 newly introduced by American Analog Devices (ADI). AD9271 is the first product that integrates 8-channel amplifier circuit and A/D converter on one chip, which is equivalent to integrating two 4-channel amplifier AD8335 and 8-channel A/D converter AD9222 on one chip. This unprecedented high-integration chip can reduce the signal channel size of the ultrasound system by 50%, reduce the power consumption by 25%, and reduce the board area by nearly 40%. At the same time, the noise level and other performances meet the requirements for detection.

Effect:

What the utility model finally obtains is the digital signal output from the AD9271. In order to verify the correctness of the design, the probe is used to detect the bottom of the water cup, and the obtained digital signal is converted into an analog signal through D/A, and the result displayed by the oscilloscope is the same as expected, which proves that the echo signal is correct. The 10M transmission pulse used in this experiment, with the increase of the transmission pulse frequency, the resolution can be improved, the detection depth is ≥50mm, the axial resolution is 150 microns, and the lateral resolution is 200 microns.

Claims (5)

1, a kind of high frequency ring battle array digitalized ultrasonic system, it is characterized in that, comprise: the ring array transducer of Xiang Lianing, receiving system, analog-digital converter, reception dynamic focusing and variable aperture control wave beam form module, digital echo synthesis module, ultrasonic signal processing module, display unit successively, also comprise processor, processor is connected with the ring array transducer by sequential control system, ultrasound emission drive system successively, and processor also forms module with analog-digital converter, reception dynamic focusing with variable aperture control wave beam respectively and is connected.

2, a kind of high frequency ring battle array digitalized ultrasonic according to claim 1 system, it is characterized in that, the ring array transducer is the five rings high frequency ring array transducer of mid frequency 10MHz, form by one group of concentrically ringed many array element crystal, the equal separate connection of each crystal is to ultrasound emission/reception drive system, the ring radius of transducer is respectively to center ring from outer shroud: 3.60mm, 3.22mm, 2.97mm, 2.28mm, 1.61mm, transducer each anchor ring in five rings is long-pending to be equated.

3, a kind of high frequency ring battle array digitalized ultrasonic according to claim 1 system is characterized in that analog-digital converter is single-chip 8 passage ultrasonic receivers, and model is AD9271.

4, a kind of high frequency ring battle array digitalized ultrasonic according to claim 1 system, it is characterized in that, the structure of ultrasound emission drive system is: the pulse signal voltage of fpga chip output forms two-way output through the voltage transitions chip, one tunnel output is connected to fet gate through electric capacity, another road output is connected to the grid of another field effect transistor, the field effect transistor drain electrode that connects electric capacity connects power supply, its source electrode connects the drain electrode and the conduct emission outfan of another field effect transistor, the source ground of another field effect transistor.

5, a kind of high frequency ring battle array digitalized ultrasonic according to claim 1 system, it is characterized in that reception dynamic focusing and variable aperture control wave beam form module, digital echo synthesis module, ultrasonic signal processing module, processor is integrated is arranged in a slice on-site programmable gate array FPGA.

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