Adaptive Amplitude and Interference Equalization
Original Publication Date: 1986-Apr-01
Included in the Prior Art Database: 2005-Mar-08
An adaptive equalization loop is described where the read signal has symmetry, is less than 4-bit periods wide, and has unknown isolated pulse amplitude. As shown in Fig. 1, the unknown amplitude is designated A and the interference is I. The signal amplitude at time N is: SN = I DN-1 + A DN +I DN+1 (1) Although this is a single equation with two unknowns (I and A), a good approximation to I and A (I and A) can be derived by using the average values I- and A- . Hence, from (1): (Image Omitted) where DN = the detected signal at time N (-1,0,1). Note: Multiplication and division by Di is simple because Di e (-1,0,1). These equations can be implemented as the embodiment of Fig. 2.