Improvement of Burst Error Correction Using a Look-Up Table with Low Density Parity Check Coding for Compressed Ultraspectral Sounder Data

Low density parity check (LDPC) codes have the ability to transmit data at rates approaching channel capacity with very low error probability. Our study of LDPC codes on JPEG2000-compressed ultraspectral sounder data shows that for an LDPC encoder designed with certain input parameters, the LDPC decoder is able to correct all single errors and two-bit burst errors. Furthermore, our analysis on a massive variety of 3- and 4-bit burst error scenarios indicates that the locations of LDPC-uncorrected errors for 3- and 4-bit burst errors appear to be fixed, regardless of the content of the input data. We propose a look-up table based error correction method to correct errors surviving from the LDPC decoder for 3- and 4-bit burst errors.

1. Introduction

Contemporary and future ultraspectral sounders (e.g. AIRS CrIS, IASI, GIFTS, and HES [1]) are expected to improve weather and climate prediction. Given the huge volume of three-dimensional data generated by an ultraspectral sounder each day, the use of robust data compression techniques will be beneficial for data transfer and archival. The physical retrieval of these geophysical parameters, involving the inverse solution of the radiative transfer equation, is a mathematically ill-posed problem [2], i.e. the solution is sensitive to the error or noise in the data. Therefore, there is a need for lossless or near lossless compression of ultraspectral sounder data to avoid potential retrieval degradation of geophysical parameters due to lossy compression. Robust error-correcting codes are also desired for satellite data transmission.