System for phase inversion ultrasonic imaging
View Patent ↗A system for ultrasonic imaging utilizing multiple sets of transmit pulses differing in amplitude, frequency, phase, and/or pulse width. One embodiment has phase differences between the k transmit signal as 360 k degrees providing for constructive interference of the k th order harmonic pulse, while an amplitude modulation of each transmit profile is constant between sets. These sets of pulses are transmitted into media of interest and received echoes from these pulses are combined to form an averaged signal. The averaged pulses represent the net common mode signal received from each of the transmit sets. This combined signal set is used to reconstruct an ultrasound image based on broad beam reconstruction methodology.
1. A system for ultrasonic imaging, comprising:
a signal generator unit for generating at least two out-of-phase pulses, wherein the signal generator unit convolves at least two out-of-phase sine waves with an envelope function to produce the at least two out-of-phase pulses, and wherein the at least two out-of-phase sine waves are modulated in a way to produce a chirped Gaussian pulse width modulated waveform;
a signal transmitter unit coupled to the signal generator unit for transmitting the at least two out-of-phase pulses into media of interest;
a receiver and raw data averager unit for receiving the at least two out-of-phase pulses modified by the media of interest, the receiver and raw data averager unit providing a point-by-point arithmetic average of the received at least two out-of-phase pulses modified by the media of interest; and
a data processing unit coupled to the receiver and raw data averager unit, the data processing unit constructing an area of acoustic image based on the point-by-point arithmetic average provided by the receiver and raw data averager unit.
2. The system of claim 1 , wherein the signal generator unit is a digital waveform generator.
3. The system of claim 1 , wherein the envelope function is a Gaussian waveform.
4. The system of claim 1 , wherein the envelope function is a chirped waveform.
5. The system of claim 1 wherein the signal transmitter unit comprises a power amplifier, a transmit/receive switch, and a transducer.
6. The system of claim 5 , further comprising a digital delay circuit configured to delay the transmission of the at least two out-of-phase pulses into media of interest.
7. The system of claim 5 , further comprising an analog delay circuit configured to delay the transmission of the at least two out-of-phase pulses into media of interest.
8. The system of claim 5 , further comprising a channel gain circuit to drive the power amplifier.
9. The system of claim 1 , wherein the at least two out-of-phase pulses are alternately transmitted by the signal transmitter unit to produce a pulse set.
10. The system of claim 1 , wherein the receiver and raw data averager unit comprises a transducer, a transmit/receive switch, an analog-to-digital converter, and an averager.
11. The system of claim 10 , wherein the receiver and raw data averager unit further comprises a power amplifier, a bandpass filter, and a baseband filter.
12. The system of claim 10 , wherein the receiver and raw data averager unit further comprises an in-phase and quadrature mixer configured to produce a single side-band signal.
13. The system of claim 1 , wherein the signal generator unit and the receiver and raw data averager unit share a transducer.
14. The system of claim 1 , wherein the data processing unit comprises an in-phase and quadrature mixer, a digital signal processor, an acoustic image data buffer, and a scan converter.
15. The system of claim 1 , wherein the data processing unit comprises an in-phase and quadrature mixer, an application specific integrated circuit, an acoustic image data buffer, and a scan converter.
16. The system of claim 1 , further comprising an image display unit coupled to the data processing unit.
17. The system of claim 16 , wherein the image display unit is a computer monitor, the computer monitor configured to display the area of acoustic image.
18. The system of claim 16 , wherein the image display unit is a flat-panel display, the flat-panel display configured to display the area of acoustic image.
19. The system of claim 16 , wherein the image display unit is a liquid-crystal display, the liquid-crystal display configured to display the area of acoustic image.