On the error detection capability of combined LDPC and CRC codes for space telecommand transmissions

We present a method for estimating the undetected error rate when a cyclic redundancy check (CRC) is performed on the output of the decoder of short low-density parity-check (LDPC) codes. This system is of interest for telecommand links, where new LDPC codes have been designed for updating the current standard. We show that these new LDPC codes combined with CRC are adequate for complying with the stringent requirements of this kind of transmissions in terms of error detection.

I. Introduction

In some applications, error detection is at least as important as error correction. This is the case of space telecommand (TC) links, where an uncorrected error may cause no command execution, when the error is detected, or wrong execution when the error is undetected.