Patent ID: 7636281

Claim:
A reading unit for reading data from a digital data carrier, the reading unit comprising: a reading head including a sensor for sensing data from the data carrier and generating a sensor signal indicative of the sensed data; a head positioning apparatus for positioning the reading head relative to the data carrier in response to a head positioning control signal; a head positioning controller for generating the head positioning control signal by processing the sensed data; and a data decoder for decoding the sensed data to form a digital output signal, the data decoder comprising: a memory including an instruction set for instructing a data processor to process a stream of data bytes generated in response to the sensed data; and a de-interleaving unit including three buffers for sequentially storing the stream of data bytes, wherein the de-interleaving unit is configured to de-interleave the stream of data bytes by: filling a first one of the three buffers with successive data bytes from the stream of data bytes; and forming an output stream by alternatingly reading data bytes from the other two of the three buffers.