Digital broadcasting receiver and signal processing method thereof

A receiver is provided. A receiving module receives M symbols that respectively include N subcarriers carrying a control signal. A converting module performs FFT on the kth subcarriers in the ith symbol and (i+1)th symbol, so as to generate an (i, k)th converting value and an (i+1, k)th converting value. A demodulating module performs differential demodulation on the (i, k)th and (i+1, k)th converting values, so as to generate an (i, k)th demodulation value. A combining module soft-combines the (i, 1)th demodulation value through the (i, N)th demodulation value, so as to generate an ith prediction value. Based on the first prediction value through the (M-1)th prediction value, a judging module looks for a synchronization word in the control signal.