Trellis Modulation
Information Theory Accomplishment | 1976
IBM researchers: Gottfried Ungerboeck
Where the work was done: IBM Zurich Research Laboratory
What we accomplished: Trellis coded modulation is a modulation scheme that transmits information with high efficiency over band-limited channels such as telephone lines. Its main attraction: It enables significant coding gains over conventional uncoded multilevel modulation without compromising bandwidth efficiency. (Gottfried Ungerboeck, pictured)
Related links: TCM; MAP Algorithm for TCM; Trellis-Coded Modulation With Redundant Signal Sets (Part I/Introduction)
Image credit: Engineering and Technology History Wiki
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