Method and apparatus for determining signal quality

A unique method and apparatus determines signal quality and/or bit reliability information for a plurality of phase modulated information symbols. This is accomplished by first detecting the phase of the received phase modulated signal (201). The resulting phase estimate is then compared against the nearest expected phase value to form a phase error signal (202). The phase error signal is then mapped into a symbol quality estimate (205/206), which is then averaged over multiple symbol intervals to form a signal quality indicator (207). Finally, bit reliability information is generated by weighting the in-phase (I) and quadrature (Q) components of the phase estimate by the derived signal quality indicator (209). With such a method and apparatus, signal quality and/or bit reliability information can be determined without the need for signal amplitude information.