A reduced high dimensional FDTS for magneto-optical recording

FDTS (Fixed Delay Tree Search) sequence detection using metric calculation is demonstrated. FDTS with a long tree depth is performed using a High Dimensional Signal Space Detector. We propose a new HD (High Dimensional)-FDTS employing a reduction algorithm under conditions of a certain minimum RLL (Run Length Limitation) of code and with ISI (intersymbol interference). We made sure that the HD-FDTS minimum distance taking account of the RLL code was close to that of a Viterbi decoder. The decoder circuit is small and high speed and has a reasonable noise margin for an ideal equalized wave with AWGN (Additive White Gaussian Noise). The HD-FDTS may be applied to PLL (Phase Locked Loop) and AGC (Automatic Gain Control) because of the short decoding delay.