Abstract: A method for a digital Communications receiver. The method comprises receiving a signal transmitted from a transmitter. The transmitted signal includes a first modulated carrier representing one or more data bits and a second modulated modulated carrier optionally representing one or more padding bits only. The padding bits are inserted at the transmitter and have predefined values known to both the transmitter and receiver. The method further comprises determining whether the one or more padding bits were inserted at the transmitter; if so, analysing the second modulated carrier in the received signal, using knowledge of the predetermined values of the one or more padding bits; and, using information determined from the analysis, estimating the values of the one or more data bits from the first modulated carrier.