Last Modified: January 9, 2017

Calculates parameters for use with either MT Modulate FSK or MT Demodulate FSK. This node generates the symbol map for FSK-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.

The *M*-ary number, which is the number of distinct frequency deviations, to use as symbols. This value must be a positive power of 2.

**Default: **2

Maximum FSK frequency deviation. At baseband frequencies, deviations for individual symbols are evenly spaced in the interval [-*f* _{ d }, *f* _{ d }], where *f* _{ d } represents the frequency deviation.

**Default: **150,000

Continuity of phase transitions between symbols.

Name | Description |
---|---|

continuous | Continuous phase transitions between symbols. |

discontinuous | Discontinuous phase transitions between symbols, that is, discontinuous phase FSK (DPFSK). With discontinuous phase-FSK (DPFSK), modulation consists of selecting the appropriate sinusoid based on the input data. Thus, when switching between symbols, there is a discontinuity in the FSK signal phase. To emulate a hardware-based DPFSK source, this node maintains the phase of each independent sinusoid versus time. Thus, the DPFSK modulator acts like a hardware-based (multiple switched tone generator) FSK modulator. |

**Default: ****continuous**

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

**Default: **no error

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

Number of samples per symbol in the modulated output complex waveform. For error-free operation, the **samples per symbol** must be an even number. Applying Carson's rule for FSK modulation, the 98% FSK bandwidth is given by the following formula:

0.5 × (1 + *r*) × *symbol rate* + *peak frequency deviation*

where 0 ≤ *r* ≤ 1 is the filter parameter.

To satisfy the Nyquist criterion, use the following guideline.

*samples per symbol* = 2 × ceil(1.5 × *bandwidth/symbol rate*) to obtain 3× oversampling.

Ordered array that maps each Boolean symbol to its desired deviation frequency. The number of FSK levels in the array must be 2^{ N }, where *N* is the number of bits per symbol.

Continuity of phase transitions between symbols.

Name | Description |
---|---|

continuous | Continuous phase transitions between symbols. |

discontinuous | Discontinuous phase transitions between symbols, that is, discontinuous phase FSK (DPFSK). With discontinuous phase-FSK (DPFSK), modulation consists of selecting the appropriate sinusoid based on the input data. Thus, when switching between symbols, there is a discontinuity in the FSK signal phase. To emulate a hardware-based DPFSK source, this node maintains the phase of each independent sinusoid versus time. Thus, the DPFSK modulator acts like a hardware-based (multiple switched tone generator) FSK modulator. |

**Default: ****continuous**

Number of bits represented by each symbol. This value is equal to Log_{ 2 }(*M*), where *M* is the order of the modulation. Example: For 16-FSK, *M* = 16.

**Where This Node Can Run: **

Desktop OS: Windows

FPGA: Not supported