BPP

From NMR Wiki

BPP - bipolar pulse pair.

BPP is a pulse sequence element (shown above) where gradient pulses of opposing intensity and equal length are separated by a 180^o RF pulse.

The effect of this element is close to a continuous gradient pulse of same intensity but equal the length of the two pulses. The benefit of this element is cancellation of eddy currents caused by the two pulses, because eddy currents will have opposite intensity. Cancellation is best when separation between the two gradients is very small - on the order of 1 ms.

References

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