Abstract

A decode apparatus for decoding a plurality of encoded messages received over a noisy transmission link, eg., a satellite link or a radio telecoms link comprises a demodulator for demodulating analogue signals to produce a digitized bit stream; an analyzer comprising a received signal strength indicator; a carrier to noise ratio measurement means; a look up table for reading data describing an optimized number of decode iterations; an array of turbo code decoders, each having an associated local storage buffer; and a scheduler means for scheduling demodulated message packets to each of the plurality of decoder processors, depending upon an estimated optimum number of decode operations required for each message packet. Allocation of the message packets to the plurality of decode processors is made such as to optimize overall utilization of the decode processors. The number of decode processors required for a system is estimated from a statistical analysis of the noise and optimum number of decode iterations required to decode an incoming time division multiplex bit stream having time division messages which differ in noise ratio, and hence require different processing powers for decoding, between successive time division multiplex messages.