MT Generate PAM System Parameters (map)
- Updated2023-02-17
- 4 minute(s) read
MT Generate PAM System Parameters (map)
Calculates parameters for use with either MT Modulate PAM or MT Demodulate PAM. The node accepts an array of symbol values that explicitly specifies the positions of the symbol map with symbols that are evenly distributed between -1 and 1.
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Inputs/Outputs

samples per symbol
An even number of samples dedicated to each symbol. Multiply this value by the symbol rate to determine the sample rate.
Default value: 16

symbol values
An array of symbol values with an index-based order that corresponds to the symbol map. The length of the symbol values array must be a positive power of 2, and the entries must be unique and in the range 0 to M-1, where M is the length of the symbol values array.
This node expects an array of integers for the symbol values parameter. The integers 0 through (M-1) must all be included only once in the symbol values array, where M is the M-ary number of the modulation. The binary representation (LSB first convention) of the integers represents the bit pattern that is mapped to the corresponding symbol location in the symbol values array. The symbol locations are evenly spaced between (-1 + 0i) and (1 + 0i), inclusive, along the real axis (I axis).
For example, for 4-PAM, if you specify symbol values as [2 3 0 1], the generated PAM symbol map is [(0.333 + 0i), (1 + 0i), (-1 + 0i), (-0.333 + 0i)].

error in
Error conditions that occur before this node runs.
The node responds to this input according to standard error behavior.
Default value: No error

PAM system parameters
Parameter values defining the PAM system. Wire this cluster to the corresponding system parameters cluster of MT Modulate PAM or MT Demodulate PAM.

samples per symbol
Number of samples per symbol in the modulated output complex waveform. For error-free operation, the samples per symbol must be an even number.

symbol map
An ordered array that maps each symbol to its desired level. The number of PAM levels in the array is 2N, where N is the number of bits per symbol. The vector length for the symbols farthest from the origin is 1.

bits per symbol
Number of bits represented by each symbol. This value is equal to Log2(M), where M is the order of the modulation (for example, for 16-PAM, M = 16).

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