Plane wave imaging has been widely used in many applications. It has high frame rate but relatively poor image quality. Coherent plane wave compounding (CPWC)is an imaging method of summing beamformed outputs of array elements from different plane wave firing events

which can significantly improve the quality. However

the coherence between the plane waves is out of consideration. In this paper

we proposed a novel method in which CPWC is weighted by the sign coherence factor (SCF-CPWC). Firstly

a vector is composed by the beamformed outputs of the multiple steered plane wave firings on the same image point. Secondly

the sign coherence factor (SCF)of the vector is calculated

and then employed to weight the corresponding output of CPWC to get the final imaging result. Both simulation and experimental results demonstrate that the proposed SCF-CPWC method has achieved a better performance than CPWC. Compared to CPWC

it can not only improve the lateral resolution

but also increase the anechoic cyst contrast.