1. A wireless transmit receive unit (WTRU) configured for use in a wireless communication system comprising: an iterative turbo decoder configured to correct communication signal data errors by recursively evaluating signal data for a selected number of iterations; the decoder including: a decoder data memory configured to store turbo decoder estimate data generated for one decoding iteration; a signature memory configured to store a code signature corresponding to turbo decoder estimate data generated for one decoding iteration; decoder circuitry configured to produce decoder estimate data for each iteration of decoding and storing it in said decoder data memory; signature code generating circuitry configured to generate a code signature corresponding to turbo decoder data for each decoder iteration such that each code signatures is at least twenty times smaller than the corresponding turbo decoder data; and a comparator operatively associated with the signature code circuitry and decoder circuitry configured to compare a generated code signature for turbo decoder estimate data being produced and stored for a present decoder iteration with the contents of the signature memory such that if the comparison reflects equality, the decoder circuitry ceases iteration processing and if the comparison reflects inequality, the generated code signature is stored in the signature memory where it is available for comparison relative to a code signature for a next decoder iteration.