Runlength-limited code with small error propagation

We present a new runlength-limited modulation technique based on the variable-length encoding principle. The code achieves minimum and maximum runlengths Tmin = 1.5 and Tmax = 4.5, respectively. Decoding is very simple and only needs an observation field of six channel bits. The new code is compared with other codes achieving Tmin = 1.5.