Various embodiments include methods and systems having detection apparatus operable to cancel or reduce leakage signal originating from a source signal being generated and transmitted from a transmitter. A leakage cancellation signal can be generated digitally, converted to an analog signal, and then subtracted in the analog domain from a received signal to provide a leakage-reduced signal for use in detection and analysis of objects. A digital cancellation signal may be generated by generating a cancellation signal in the frequency domain and converting it to the time domain. Optionally, an estimate of a residual leakage signal can be generated and applied to reduce residual leakage remaining in the leakage-reduced signal. Additional apparatus, systems, and methods can be implemented in a variety of applications.

A passband characteristic of a band pass filter is adapted to an examinee while a texture of an ultrasound image is maintained or is not significantly changed. A passband characteristic of a BPF is dynamically changed in accordance with a depth of an observation point (reception focus). The passband characteristic includes convex forms, and the convex forms have peaks as highest points in a gain axis direction and have widths in a frequency axis direction. A peak position is relatively changed with respect to the width while an upper limit and a lower limit of the width are substantially maintained. Accordingly, the convex forms are biased to a low-frequency side or a high-frequency side.

An imaging system that utilizes deterministic bit sequences modulated onto an in-phase component of a carrier frequency and continuously transmitted via a transducer and received for imaging a medium and/or environment is provided. The received signal is demodulated by an in-phase demodulator and a quadrature demodulator and the demodulated components are processed to provide a spatial mapping of a medium or environment being imaged.

An object information acquiring apparatus includes a probe configured to irradiate ultrasonic waves to an object, receive ultrasonic echoes, and convert the ultrasonic echoes into electric signals, a scanning unit configured to cause the probe to perform back-and-forth scanning on the object, an ultrasonic control unit configured to control irradiation of ultrasonic waves, a signal processing unit configured to obtain an ultrasonic, and a combining unit configured to combine a plurality of ultrasonic images. The scanning unit causes the probe to perform back-and-forth scanning on the object such that regions subjected to ultrasonic irradiation performed by the probe in forward and backward paths in the back-and-forth scanning overlap with each other. The ultrasonic control unit employs different methods for irradiating ultrasonic waves in the forward and backward paths. The combining unit combines a plurality of ultrasonic images with one another.

An ultrasonic device includes a plurality of ultrasonic element groups each including at least one transmitting element adapted to transmit an ultrasonic wave and at least one receiving element adapted to receive an ultrasonic wave, and arranged along an X direction, and in each of the ultrasonic element groups, a centroid position of the receiving area, in which the receiving element included in the ultrasonic element group is disposed, overlaps a transmitting area, in which the transmitting element included in the ultrasonic element group is disposed, in a projection view along a Y direction.

A passband characteristic of a band pass filter is adapted to an examinee while a texture of an ultrasound image is maintained or is not significantly changed. A passband characteristic of a BPF is dynamically changed in accordance with a depth of an observation point (reception focus). The passband characteristic includes convex forms, and the convex forms have peaks as highest points in a gain axis direction and have widths in a frequency axis direction. A peak position is relatively changed with respect to the width while an upper limit and a lower limit of the width are substantially maintained. Accordingly, the convex forms are biased to a low-frequency side or a high-frequency side.

A method for performing acoustic imaging and measurements may include generating a nonlinear frequency modulation (NLFM) chirp waveform based on a frequency response of at least one transducer. The method may further include generating an apodized signal by applying a window function to the NLFM chirp waveform. The method may further include exciting the at least one transducer with the apodized signal. The method may further include compressing received signals by using one or more matched filters.