Speckle Reduction for Ultrasonic Imaging Using Frequency Compounding and Despeckling Filters along with Coded Excitation and Pulse Compression

Table 2

CNR, HO, 𝐻_diff, and cSNR for the 15 mm ATS phantom target.

Technique^1	CNR	HO	𝐻diff	cSNR
CP	0.56	32.49	16.06	—
REC	0.62	32.49	17.61	8.23
REC-FC (third-width)	1.73	14.07	43.17	12.82
eREC-FC	1.60	17.22	37.64	8.72
eREC-FC and median filtering	2.29	12.12	45.43	8.08
eREC-FC and Lee filtering	2.57	12.09	44.89	8.14
eREC-FC and HMA filtering	2.51	13.41	43.98	8.12
eREC-FC and geometric filtering	1.83	15.17	37.67	10.07
eREC-FC and SRAD filtering	1.86	10.65	40.49	18.32

1CP: conventional pulsing; REC: resolution enhancement compression; FC: frequency compounding; eREC-FC: enhanced REC-FC; HMA: homogeneous mask area filtering; SRAD: speckle reducing anisotropic diffusion.