IMT Mixer (CE)

Mixer model with the usage of intermodulation table (IMT).

blockType: SubSystem

Path in the library:

/RF/Circuit Envelope/Elements/IMT Mixer (CE)

Description

Block IMT Mixer (CE) It is used to perform the frequency conversion defined in the intermodulation table (see [1], [2]) for a single-tone carrier signal mixed with a reference oscillator (LO) signal. The block takes into account nonlinear amplification , as well as parasitic components. For a single-tone carrier signal , nonlinearly modulated by a reference oscillator signal with a frequency of intermodulation components at the output of the mixer occur at frequencies:

Where

— the carrier frequency of the input radio frequency (RF) signal;
— frequency of the reference generator;
and — non - negative integers (from 0 up to the order of nonlinearity);

The main harmonics can be considered . All other combinations and they are parasitic intermodulation components.

Ports

Conserving

# In+ — RF input signal
electricity

Details

A positive electrical port connected to the RF input signal.

Program usage name

In+

# In- — RF input signal
electricity

Details

A negative electrical port connected to the RF input signal.

Program usage name

In-

# Out+ — The output signal
electricity

Details

A positive electrical port connected to the output signal.

Program usage name

Out+

# Out- — The output signal
electricity

Details

The negative electrical port connected to the output signal.

Program usage name

Out-

Parameters

Main

# Carrier frequency, Hz — carrier frequency

Details

The carrier frequency in Hz, set as a scalar. When multiple carriers are present at the input connection, the carrier frequency set in this parameter is selected as the RF input signal. The distance between adjacent carriers must be greater than .

Default value	`1e9`
Program usage name	`carrier_freq`
Tunable	No
Evaluatable	Yes

# Local oscillator frequency, Hz — frequency of the reference oscillator

Details

The frequency of the reference oscillator in Hz, set as a scalar.

Default value	`1e8`
Program usage name	`LO_freq`
Tunable	No
Evaluatable	Yes

# Reference input power, dBm — reference input power

Details

The reference input power in dBm, set as a scalar. The expression for the normalized input signal at a given reference input power has the form:

where — parameter value Reference input power, dBm.

The intermodulation tables assume that the levels of parasitic components are measured for reference input and output power. For example, if you increase the input power by 10 dB, then the parasitic components caused by second-order nonlinearity will increase by 20 dB, and the parasitic components caused by third—order nonlinearity are 30 dB and so on.

Default value	`-10`
Program usage name	`reference_input_power`
Tunable	No
Evaluatable	Yes

# Nominal output power, dBm — rated power of the reference generator

Details

Rated output power in dBm, set as a scalar. The expression for the normalized output signal at a given reference input power has the form:

where — parameter value Nominal output power, dBm.

Default value	`-20`
Program usage name	`nominal_output_power`
Tunable	No
Evaluatable	Yes

# Input impedance, Ohm — mixer input resistance

Details

The input resistance of the mixer in ohms, set as a real scalar.

For input and output resistances not equal 50 Ohms, the IMT data is normalized to 50 Om.

Default value	`50`
Program usage name	`R_in`
Tunable	No
Evaluatable	Yes

# Output impedance, Ohm — mixer output resistance

Details

The output resistance of the mixer in ohms, set as a real scalar.

For input and output resistances not equal 50 Ohms, the IMT data is normalized to 50 Om.

Default value	`50`
Program usage name	`R_out`
Tunable	No
Evaluatable	Yes

IMT

# IM Table — inharmonic spectral components

Details

Inharmonic spectral components of IMT, defined as a square matrix.

Default value	`[99.0 99.0 99.0; 99.0 0.0 99.0; 99.0 99.0 99.0]`
Program usage name	`imt`
Tunable	No
Evaluatable	Yes

Literature

Faria, Daniel. Lawrence Dunleavy, and Terje Svensen. The Use of Intermodulation Tables for Mixer Simulations. Microwave Journal, April 2002. https://www.microwavejournal.com/articles/3430-the-use-of-intermodulation-tables-for-mixer-simulations
RF Mixing / Multiplication: Frequency Mixers. Electronic Notes. https://www.electronics-notes.com/articles/radio/rf-mixer/rf-mixing-basics.php