US Patent 11539605 Channel quality determination

This application relates to determining transmission quality of a communication channel, in particular for determining a measure of errors in data transmitted as multi-bit symbols. Described is an error checker with an input for receiving an input signal comprising a series of modulated symbols, wherein each symbol encodes multiple bits of a pseudo-random bit sequence. A demodulator is configured to receive the input signal and only partially demodulate at least some of the symbols to generate a partially demodulated bit sequence. A PRBS module is configured to receive the partially demodulated bit sequence and determine the pseudo-random bit sequence and a comparator compares the output of the demodulator to an expected output based on the pseudo-random bit sequence determined by the PRBS module.