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Maps complex-valued QAM symbols to an output bit stream based on a user-specified symbol map.

Programming Patterns
Use this node in conjunction with MT Matched Filter, MT Align to Ideal Symbols, MT Decimate Oversampled Waveform, and MT Calculate BER to perform waveform analysis on the modulated waveform.

The mapping of symbols to bits depends on the number of bits per symbol, which equals log 2 ( M ) with M representing the size of the modulation scheme. For example, in a 256-QAM system, 500 QAM symbols are mapped to ( 500 ) × log 2 ( 256 ) = 4000 m e s s a g e b i t s .



The incoming complex-valued symbols to be mapped to the output bit stream based on the symbol map.


symbol map

An ordered array that maps each symbol value to its desired coordinates in the complex plane.

The number of QAM states in the array must be 2 N , where N is the number of bits per symbol. The length of the vector for the symbols farthest from the origin must be 1. To specify a prebuilt map, unbundle the symbol map element from the QAM system parameters cluster generated by MT Generate QAM System Parameters (M) or MT Generate QAM System Parameters (map).


error in

Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.

Default: no error


output bit stream

A bit stream with a one-to-one mapping to the input symbols based on the specified symbol map.


error out

Error information. The node produces this output according to standard error behavior.