Adaptive clutter filtering method and ultrasound system for the same
View Patent ↗There is disclosed an embodiment for adaptive clutter filtering. A signal acquisition unit transmits and receives ultrasound signals to and from a target object to output baseband IQ signals. A memory stores an error condition, a filter decision condition and information on at least two of filters for filtering the baseband IQ signals. A user interface receives a filter selection condition for selecting at least two filters among a plurality of filters stored in the memory. A processor extracts at least two of filters from the memory according to the filter selection condition and the error condition, decides a filter among the extracted at least two of filters and filters the baseband IQ signals by using filter coefficients of the decided filter.
1. An ultrasound system, comprising:
a signal acquisition device, including at least an ultrasound probe, configured to transmit and receive ultrasound signals to and from a target object to output baseband In-phase Quadrature (IQ) signals;
a memory configured to store a filter table, an error condition, a filter decision condition and information on a plurality of filters for filtering the baseband IQ signals;
a user interface unit, connected to the memory, configured to receive a filter selection condition for selecting at least two filters among the plurality of filters stored in the memory; and
a processor, connected to the memory, configured to extract at least two filters from the filter table according to the filter selection condition and the error condition, select a filter among the extracted at least two filters and filter the baseband IQ signals by using filter coefficients of the selected filter.
2. The ultrasound system of claim 1 , wherein the signal acquisition device comprises:
a transmit (Tx) signal generator connected to the ultrasound probe and configured to generate Tx signals, wherein the ultrasound probe is configured to transmit ultrasound signals to the target object in response to the Tx signals and receive ultrasound echo signals reflected from the target object to output the received signals;
a beam former, connected to the ultrasound probe, configured to convert the received signals into digital signals and apply delays to the digital signals in consideration of distances between transducer elements and focal points to output digital receive-focused signals; and
an IQ signal former, connected to the ultrasound probe, configured to perform decimation on the digital receive-focused signals to form the baseband IQ signal.
3. The ultrasound system of claim 1 , wherein the filter selection condition is defined by at least one of an ensemble number, a cutoff frequency, a stopband attenuation, a filter order and a passband ripple.
4. The ultrasound system of claim 1 , wherein the error condition includes a permissible matching range with respect to the filter selection condition.
5. The ultrasound system of claim 1 , wherein the filter decision condition includes one of a condition for selecting a filter having a widest stopband, a condition for selecting a filter having a narrowest transitionband and a condition for selecting a filter having a desired phase response, with respect to each other.
6. An adaptive clutter filtering method in an ultrasound system including a signal acquisition device comprising at least an ultrasound probe, a memory, a user interface unit connected to the memory, and a processor connected to the memory, the method comprising:
transmitting and receiving, by the signal acquisition device, ultrasound signals to and from a target object to output baseband In-phase Quadrature (IQ) signals;
receiving, by the user interface unit, a filter selection condition for selecting at least two filters among a plurality of filters stored in the memory, wherein the memory stores the filter selection condition, an error condition and a filter decision condition;
extracting, by the processor, at least two filters from a filter table according to the filter selection condition and the error condition;
selecting, by the processor, a filter among the extracted at least two filters based on the filter decision condition; and
filtering, by the processor, the baseband IQ signals by using filter coefficients of the selected filter.
7. The method of claim 6 , wherein the transmitting and receiving ultrasound signals comprises:
generating, by the signal acquisition device, transmit (Tx) signals;
transmitting, by the signal acquisition device, ultrasound signals to the target object in response to the Tx signals and receiving ultrasound echo signals reflected from the target object to output the received signals;
converting, by the signal acquisition device, the received signals into digital signals and applying delays to the digital signals in consideration of distances between transducer elements and focal points to output digital receive-focused signals; and
performing, by the signal acquisition device, decimation on the digital receive-focused signals to form the baseband IQ signal.
8. The method of claim 6 , wherein the filter selection condition is defined by at least one of an ensemble number, a cutoff frequency, a stopband attenuation, a filter order and a passband ripple.
9. The method of claim 6 , wherein the error condition includes a permissible matching range with respect to the filter selection condition.
10. The method of claim 6 , wherein the filter decision condition includes one of a condition for selecting a filter having a widest stopband, a condition for selecting a filter having a narrowest transitionband and a condition for selecting a filter having a desired phase response, with respect to each other.