Inter-track orthogonal coding for ultra high track density recording

New inter-track orthogonal coding for high track density and multi-track recording is proposed. Two data code sequences are modulated by 2nd order Hadamard matrix elements so that they are orthogonal each other. The coding method exhibits an absolutely high rejection efficiency against cross talk noise from adjacent tracks, indicating feasibility not only of high track density recording but of collective reading of multi-track channel signals. It is expected from simulation results that an ultra high track density recording with neither guard-band nor azimuth between adjacent tracks would be possible for all kinds of information recording using sequential tracking