METHOD FOR A SYMBOL ENUMERATION ORDERING PROCEDURE AND AN APPARATUS USING THE METHOD

摘要

The invention discloses a method for a symbol enumeration ordering procedure and an apparatus using the method. The objection of the invention to allow an accurate and efficient calculation of the metrics and a determination of the optimum search order of the constellation symbols with low complexity are solved by a method comprising the steps of a) computing quadrature components √Q of partial metrics (I) in (II) and (III); b) sorting the quadrature components in ascending order; c) selecting a global minimum as a first symbol (IV) in an enumeration sequence; d) expanding a maximum of two new candidates for the next symbols within a metrics matrix, one along (II) and one along (III); e) adding the newly determined enumeration candidate(s) or symbols to a stack and sorting them in ascending order of their partial metrics (V); f) selecting the next symbol to be explored within the enumeration ordering procedure; g) removing the selected symbol from the stack; h) repeating steps d) to g) for enumerating further symbols.