Diagnostic medical ultrasonic imaging method and system for selectively processing harmonic and fundamental image information

A diagnostic medical ultrasonic imaging method and system form first and second signals as a function of the Nth power of the absolute value of first and second ultrasound receive signals. These receive signals are associated with respective first and second transmit pulses that differ in phase and are both associated with overlapping or nearby regions of a subject. A combined signal is formed as a function of the difference between the first and second signals. The low pass component of the absolute value of this combined signal is then applied to an image processor. This low pass component, depending upon the value of N, can correspond to the second harmonic component of the combined receive signals, to the product of the fundamental and second harmonic components of the combined receive signals, and other combinations of fundamental and harmonic components.