Patent ID: 8311297

Claim:
A method for Doppler scan conversion, comprising: caching image data of a current Doppler line, which includes spectrum data and values of N types of envelopes, in an embedded memory of a logic device; comparing the value of each type of the envelopes of the current Doppler line with that of the same type of envelope of a neighboring Doppler line for envelope alignment to obtain a starting point value Min_track(j) and an end point value Max_track(j) of line section of each type of the envelopes of the current Doppler line, wherein j is the serial number of the envelope, and j=0, 1, 2, . . . , N−1, and registering the starting point value Min_track(j) and the end point value Max_track(j) of the line section of each type of the envelopes of the current Doppler line in an internal register of the logic device; reading out the spectrum data of the current Doppler line as well as the starting point value Min_track(j) and the end point value Max_track(j) of the line section of each type of the envelopes of the current Doppler line from the embedded memory of the logic device; with respect to each dot of the spectrum data on the current Doppler line, within the transmission clock cycle corresponding to each of the spectrum data dots and dot by dot: (1) calculating the serial number Dot_NO=i+1 of a current spectrum data dot on the current Doppler line, wherein i=0, 1, 2, . . . , K−1, and K is the number of the spectrum data dots on the current Doppler line; (2) comparing the Dot_NO value corresponding to the current spectrum data dot on the current Doppler line with the starting point value Min_track(j) and the end point value Max_track(j) of the line section of each type of the envelopes of the current Doppler line; if the Dot_NO value corresponding to the current spectrum data dot on the current Doppler line is between the starting point value Min_track(j) and the end point value Max_track(j) of line section of a certain type of envelope of the current Doppler line, an envelope code Track_code[j] corresponding to that type of envelope is 1; otherwise the envelope code Track_code[j] corresponding to that type of envelope is 0; whereby a N-bit envelope code Track_code[N−1:0] is obtained; (3) combining the N-bit envelope code Track_code[N−1:0] with the spectrum data value corresponding to the current spectrum data dot on the current Doppler line to obtain combined Doppler data, and storing the combined Doppler data in a scan conversion memory, wherein the number N of the types of the envelopes is smaller than difference between bit width of the scan conversion memory and that of the spectrum data.