| Passband modulation | |||
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| Analog modulation | |||
| Digital modulation | |||
| Hierarchical modulation | |||
| Spread spectrum | |||
| See also | |||
A new modulation methodedit A Trellis diagram. A valid path through the trellis is shown as a red line. Solid lines indicate transitions where a "0" was inputted and dashed lines indicate a "1" was inputted. Hence, this image represents the bit string "1010" encoded as "00 00 10 01 10"
The name trellis derives from the fact that a state diagram of the technique closely resembles a trellis lattice. The scheme is basically a convolutional code of rates (r, r+1). Ungerboeck's unique contribution is to apply the parity check for each symbol, instead of the older technique of applying it to the bit stream then modulating the bits.
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