Facsimile compression through demodulation in packet networks

Recent years have seen widespread deployment of packetized circuit multiplication equipment (PCME) and digital circuit multiplication equipment (DCME) on international transmission facilities. Both use digital speech interpolation and low rate encoding to increase traffic concentrations on the available facilities and are designed to achieve compression ratios of 5:1 or more for voice traffic. If a significant amount of facsimile traffic is being carried, however, the advantages are significantly reduced. The Facsimile Demodulation and Compression Protocol (FADCOMP) specified as part of CCITT Recommendation G.765 and its implementation and performance in the AT&T integrated Access and Crossconnect System (IACS) are described. Field data are presented to demonstrate compression ratios similar to those for voice, while service transparency is maintained.<
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