An adaptive half duplex data transmission FEC/ARQ procedure: results on real HF ionospheric channel

An automatic data rate adaptation is described for HF modems in degraded ionospheric propagation conditions by associating rate compatible punctured codes with a dedicated automatic repeat request procedure. Real transmission of data files with a 3 kHz high rate modem is up to 2.6 kb/s automatically accorded with the channel capacity. TCM codes may extend throughput up to 3.8 kb/s with the same ARQ procedure.<
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