1. A receiver for recovering a digital data signal transmitted over a digital voice channel of a wireless telecommunications network comprising: a feature extraction module configured to receive an audio frequency waveform encoding the digital data signal transmitted over the digital voice channel of the wireless telecommunications network and generate a first feature vector describing the audio frequency waveform; a memory configured to store one or more feature vectors; and a bit sequence estimation module configured to analyze the first feature vector and generate a first estimated bit sequence corresponding to the digital data signal, wherein the bit sequence estimation module comprises a time diversity combining component configured to generate a second estimated bit sequence by analyzing the first feature vector in combination with one or more feature vectors stored in the memory.