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Calculates parameters for use with either MT Modulate PSK or MT Demodulate PSK. This node generates the symbol map for PSK-modulated systems. This node accepts an M-ary value that specifies a predefined symbol map with the number of distinct symbol map values to use as symbols.

Example Symbol Map for PSK

This symbol map corresponds to input symbol values {0, 1, 3, 2} for a quadrature-phase-shift-keying (QPSK) modulation system.

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samples per symbol

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

Note  

The demodulation and detector nodes use timing recovery, which is optimized for four or more samples per symbol.

Default: 16

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M-PSK

The M-ary number, which is the number of distinct states that represent symbols in the complex baseband modulated waveform. This value must be a positive power of 2.

Default: 4

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differential PSK

A value that indicates how the PSK modulation represents symbols.

Differential operation is used to implement PSK formats such as differential quadrature PSK (DQPSK) and π /4-DQPSK.

disable

Symbols are represented as constellation points.

enable

Symbols are represented as the transitions between constellation points.

Default: disable

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error in

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

Default: no error

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PSK type

Type of PSK modulation.

normal

Sets the modulation type to regular PSK.

shifted

Rotates the constellation by π /M each symbol.

offset

Sets the modulation type to offset quadrature phase-shift keying (OQPSK). This modulation scheme is a form of phase-shift keying in which four different phase angles are used. This scheme is sometimes referred to as staggered quadrature phase-shift keying (SQPSK). For offset PSK, the ideal symbol timing for Q is offset by 1/2 of a symbol period from the ideal symbol timing for I. offset is currently only supported for M= 4.

Default: normal

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PSK system parameters

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

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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.

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symbol map

An ordered array that maps each Boolean symbol to its desired coordinates in the complex plane. The number of PSK states in the array must be 2 N , where N is the number of bits per symbol.

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differential PSK

A value that indicates how the PSK modulation represents symbols.

Differential operation is used to implement PSK formats such as differential quadrature PSK (DQPSK) and π /4-DQPSK.

disable

Symbols are represented as constellation points.

enable

Symbols are represented as the transitions between constellation points.

Default: disable

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PSK type

Type of PSK modulation.

normal

Sets the modulation type to regular PSK.

shifted

Rotates the constellation by π /M each symbol.

offset

Sets the modulation type to offset quadrature phase-shift keying (OQPSK). This modulation scheme is a form of phase-shift keying in which four different phase angles are used. This scheme is sometimes referred to as staggered quadrature phase-shift keying (SQPSK). For offset PSK, the ideal symbol timing for Q is offset by 1/2 of a symbol period from the ideal symbol timing for I. offset is currently only supported for M= 4.

Default: normal

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bits per symbol

Number of bits represented by each symbol. This value is equal to Log 2 (M), where M is the order of the modulation (for example, for 16-PSK, M = 16).

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error out

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