Increasing the frequency of the transmitted power improves the image quality of ultrasound, but the improvement in resolution results in a decreased signal to noise ratio (SNR). Higher acoustic power levels can prevent the loss in SNR, but among other reasons, ultrasound regulations limit this to avoid heating or cavitation.
Coded excitation increase the signal to noise ratio without the loss of resolution by using coded waveforms. Coded excitation allows transmitting a long wide-band pulse with more acoustic power and high penetration of the sound beam.

The perfect image quality is dependent on some assumptions of the propagation of ultrasound waves in tissues after generating in an imaging system. These assumptions are important for the developing of optimal ultrasound imaging systems.
A lot of steps can be taken to prevent artifacts and to improve image quality, for example beamforming is used to focus the ultrasound beam, and contrast agents decrease the reflectivity of the undesired interfaces or increase the backscattered echoes from the desired regions.

See also Coded Excitation, Validation and Refraction Artifact, Q-Value, Ultrasound Phantom, Dead Zone, Narrow Bandwidth.

From GE Healthcare.;
Versatile High Performance System 'The LOGIQ 5 Expert ultrasound system delivers the premium performance advantage of TruScan architecture in a versatile high performance package. Advanced capabilities for outstanding clinical performance are available with the efficiency and productivity needed to meet clinical demands.'

From GE Healthcare.;
'GE is defining a new age of ultrasound. We call it Volume Ultrasound. GE's Voluson 730 Expert is a powerful system that enables real-time techniques for acquiring, navigating and analyzing volumetric images so that you can make clinical decisions with unprecedented confidence.'

The waveform is the record of a signal that varies over time. A blood flow signal for example, usually varies periodically with the cardiac cycle.

See also Coded Excitation, and Pulse Volume Recording.