Patent ID: 7849377

Claim:
SISO decoder for iteratively decoding a block of received information symbols (r), in particular for use in a turbo decoder, said block being divided into a number of windows of information symbols, said SISO decoder comprising: at least one SISO decoding unit ( 17 , 21 ) for SISO decoding of the received information symbols (r) of a window, a window activity flag storage ( 23 ) for storing window activity flags indicating if a window is made active or inactive, a window activity flag setting unit ( 17 ) for setting said window activity flag active or inactive, wherein said window activity flags are initially set active and wherein a window activity flag of a window is set inactive if a certitude indication value of the information symbols in said window are above a predetermined certitude threshold, a window activity flag reading unit ( 17 , 22 ) for reading said window activity flags from said window activity flag storage ( 23 ), and a control unit ( 27 ) for controlling said at least one SISO decoding unit ( 17 ) based on the read window activity flags such that the information symbols of a window for, which the corresponding window activity flag is set inactive are not SISO decoded in subsequent iterations.