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A new diversity technique is proposed to combat Rayleigh fading in digital mobile radio system transmitting speech signals. The speech signals are my-law PCM encoded, and alternate data words are used to form two streams called 'odd' and 'even'. The even stream is delayed by tau seconds and the streams are interleaved prior to radio transmission using two-level PSK modulation. At the receiver the odd data stream is delayed by tau and interleaved with the even stream. Consequently if an error burst occurs the effect of the reshuffling of the data stream is, in general, to place words with bit errors in juxtaposition to those correctly received. After micro-law PCM decoding of the words, a statistical error detection strategy is evoked to identify the erroneous samples. These samples are replaced by adjacent sample interpolation to give the recovered speech sequence. No recourse to channel protection coding is made. In our experiments a Rayleigh fading envelope was generated from a hardware simulator and stored in a computer, along with four sentences of speech. The system was then simulated and the recovered speech perceived.