N_StateMod (N-State Modulator)
Symbol
Available in ADS
Parameters
Name |
Description |
Units |
Default |
---|---|---|---|
MaxStates |
Maximum number of input states |
None |
4 |
StateArray |
Complex array of state values |
None |
list(1+j,-1+j,-1-j,1-j) |
Fnom |
Nominal input frequency |
GHz |
1 |
Rout |
Output resistance |
Ohm |
50 |
Notes/Equations
- This N-state modulator can be used to create an arbitrary, user-defined constellation of complex modulation states. The input harmonic closest to the specified Fnom frequency is selected and modulated by a sequence of complex states.
If there is no analysis harmonic frequency close enough to the Fnom frequency, a warning is issued and the output is 0. The states are defined by the complex array variable StateArray. The sequence of states is determined by the baseband component of the state modulation input. The two input impedances are infinite; output impedance is set by Rout, and is limited to a minimum value of 0.1 Ohm. The open circuit output voltage is defined by
where
k represents the value at the analysis harmonic frequency closest to the Fnom value
0 represents the baseband component of the modulation state input voltage; this input voltage is internally limited to be between 0 and MaxStates −1.
The StateArray variable can be created from list of complex values using the list( ) function. - This model will not function as a complex modulator in transient and baseband envelope simulations if complex state values are specified.
- 16-State Modulation Example and Simulation Results show a schematic example and simulation results for a 16-state modulator being swept linearly through all 16 of its states.
16-State Modulation Example