Coded excitation imaging for use with bipolar, unipolar and other waveforms

An ultrasound transmitter for suppressing sidelobe levels in ultrasound imaging, the transmitter comprising:

• a waveform generator operable to generate a first waveform in response to pulse width modulation in addition to coding, the first waveform being a pulse width modulated, coded waveform and having pulse widths that vary as a function of each of the coding and the pulse width modulation;
• and
• a transducer connected with the waveform generator, the transducer operative to receive the first waveform.

A transmit method for suppressing sidelobe levels in ultrasound imaging, the method comprising:

• (a) generating a first waveform having fewer than four amplitude levels, the first waveform having an amplitude spectrum function that varies as a function of a frequency response characteristic of a transducer;
• and
• (b) applying the first waveform to the transducer, the frequency response characteristic of the transducer operable to filter the first waveform such that the first waveform has more second harmonic energy than a transmitted acoustic wave at a face of the transducer.

An ultrasound transmitter for suppressing sidelobe levels in ultrasound imaging, the transmitter comprising:

• a transducer having a frequency response characteristic;
• and
• a waveform generator operable to generate a first waveform having fewer than four amplitude levels, the first waveform having an amplitude spectrum function that varies as a function of the frequency response characteristic of the transducer such that a transmitted acoustic energy at the face of the transducer responsive to the first waveform has less second harmonic energy than the first waveform.