A receiver of digital data bursts is provided comprising an antenna array, a first space time filter having filter coefficients initialized by estimation over just training data in a received burst and providing symbol estimates and a second space time filter having filter coefficients initialized by estimation over the received burst and providing symbol estimates. In use at least one pass to determine a symbol estimate in the received burst is undertaken by each space time filter and a selector operates to determine which of the first and second filters provides the symbol estimate closer to an expected value.