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MixerIMT (Obsolete Intermodulation Table Mixer)

Symbols:

Available in ADS

Parameters
Name Description Units Default
SS_SideBand Produce UPPER or LOWER sideband at output port for linear analysis. None UPPER
ConvGain † Conversion gain multiplier from RF port (Port 1) to IF port (Port 2). None dbpolar(0,0)
SP11 † RF port reflection coefficient. None polar(0,0)
SP22 † IF port reflection coefficient. None polar(0,180)
SP33 † LO port reflection coefficient. None 0
NF Input double side band noise figure; must be a non-negative real number. dB None
NFmin Minimum double sideband noise figure at Sopt; must be a positive real number. dB None
Sopt † Optimum source reflection for minimum noise figure; must have magnitude less than 1.0.
Rn Equivalent noise resistance; must be a non-negative real number. Ohm
R1 Reference impedance for RF port; must be a non-negative real number. Ohm
R2 Reference impedance for IF port; must be a non-negative real number. Ohm
R3 Reference impedance for LO port; must be a non-negative real number. Ohm
InThresh Voltage threshold for signal input at RF port; must be a positive real number. V
LoThresh Voltage threshold for signal input at LO port; must be a positive real number. V
IMT_File File containing intermodulation table. Accepted formats MDIF: IMT, P2D, S2D. imtfile.imt
† These parameters can be reported in any of the following complex number formats: x + j*y, polar(x,y), dbpolar(x,y), vswrpolar(x,y)

Notes/Equations
  1. This component is included for the convenience of customers who have existing designs with the MixerIMT model. New instances can be accessed by typing MixerIMT into the Component History field in the Schematic window, pressing Enter, and moving your cursor to the drawing area to place it. For new designs, this component should be used only if MixIMT_Data does not provide necessary functionality.
  2. MixerIMT does not function in Transient simulations; MixerIMT blocks baseband signals in Circuit Envelope simulations; MixerIMT does not produce intermodulation among RF input tones (refer to note 9). Replace MixerIMT with MixerIMT2 for these functions.
  3. The default value of S12=0 to avoid creating cyclic interdependencies between the RF and IF ports.
  4. If no IMT file is referenced, the output (IF) signal is the product of the input RF and LO spectral tones only.
  5. If NFmin , Sopt , and Rn are used to characterize noise, the following criteria must be met for a realistic model:

    Rn will be reset to a value that meets this criteria if it does not satisfy this condition.
  6. Use the function polar(mag,ang), or dbpolar(dB,ang), or VSWRpolar(VSWR, ang) to convert these specifications into a complex number.
  7. For an S-parameter or a noise figure sinusoidal ripple, use the function ripple (mag, intercept, period, variable); for example ripple(0-1, 0-1, 10 MHz, Freq).
    Example: S21=dbpolar(10+ripple( ),0.)
  8. This model blocks dc.
  9. MixerIMT accepts only O-type IMT files where only single RF on single LO mixing can be specified with implicit assumption about reference RF and LO frequencies. These files are inherently single side banded descriptions of mixer behavior and do not contain IF phase information. For details on various IMT file formats see Working with Data Files > IMT Format. From such a file, MixerIMT produces intermodulation products at frequencies 
    |m × LO\+/- n × Signal|
    where 
    -M ≤ m  ≤ M and -N ≤ n ≤ N
    Also, M and N are the orders for LO and RF signal frequencies set in the Harmonic Balance or Circuit Envelope simulation controllers.
    If there are multiple frequencies at the RF and LO ports, there will be a superposition of the RF-LO intermodulation tones. For example, given the frequencies LO 1 and LO 2 at the LO port, and Signal 1 and Signal 2 at the RF port, there will be intermodulation products at the frequencies:

    |m × LO1 +/- n × Signal1|, |m × LO1 +/- n × Signal2|,

    |m × LO2 +/- n × Signal1|, |m × LO2 +/- n × Signal2|
    where

    -M_RF ≤ m ≤ M_RF and - N_LO_ ≤ n ≤ N_LO
    There will be no products at | LO 1 +/- LO 2|, | Signal 1 +/- Signal 2| or any other RF or LO self-modulation products.
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