Modulation Code and Signal Characteristics for Signal Waveform Modulation Optical Disc

Abstract

A high-efficient and novel varying-level multilevel run-length-limited modulation code is proposed for signal waveform modulation (SWM) optical discs. The proposed code is composed of a maximum transition run (MTR) code and a level modulation process. The MTR code is employed to realize high code rate and satisfy the requirements of channels. Level modulation is used to eliminate inappropriate codewords for SWM channels and determine the level numbers for different runs. The rate of the presented code is 7/8 bits/symbols, and the recording density parameter RBPF (recording bits per 400 nm) is 2.26, which is 50.7% more than that of a digital versatile disc (DVD). The realization of the proposed code in SWM discs and the corresponding signal characteristics are also shown. With the run-length detection and level detection solution, the bit error rate (BER) is less than 2×10-4, which is feasible for SWM multilevel optical discs.

Improved partial response maximum likelihood method combining modulation code for signal waveform modulation multi-level disc

“…To obtain higher code rate and increase the storage density of the optical disc, a new bimodulation code is proposed for the SWM ML disc. [9,10] The equalization and detection technology for the SWM ML discs is a key technology. Our team has proposed a simple method to detect the readout signal of the SWM ML discs, [11] which can meet the partial requirements.…”