A method of operation of a communication system includes: retaining an a-posteriori detector-data, a detector-extrinsic-information, an a-posteriori-decoder-data, a decoder-extrinsic-value, or a combination thereof calculated from a received signal; determining an a-priori-decoder-information or an a-priori detector-information from the a-posteriori detector-data, the detector-extrinsic-information, the a-posteriori-decoder-data, the decoder-extrinsic-value, or a combination thereof; and adjusting the a-posteriori detector-data, the detector-extrinsic-information, the a-posteriori-decoder-data, the decoder-extrinsic-value, or a combination thereof using the a-priori-decoder-information or the a-priori detector-information for communicating through a device.