Need Help? Talk to an Expert

Modular Instruments

Model SC2250

18 GHz Frequency Extension and Signal Conditioning Module

The SC2250 extends the useful range of traditional 6 GHz RF instruments for operation at microwave frequencies up to 18 GHz. It provides excellent integration capability with other modular products such as National Instruments’ Vector Signal Transceiver (VST). Selectable filtering is provided for signal conditioning applications requiring spurious and harmonic rejection.


Typical Applications

  • Harmonic level measurements to 18 GHz in production test
  • Intermediate Frequency Interface for 5G Research and Development
  • 802.11ax (U-NII-5 5925-6425 MHz, U-NII-6 6425-6525 MHz, U-NII-7 6525-6875 MHz, U-NII-8 6875-7125 MHz) testing on legacy 6 GHz Instruments

Both up- and down-conversion functions are housed in a single-slot PXIe module. An independent local oscillator (LO) is available for each block. Optional LO input ports are provided to support measurements requiring extremely low phase noise performance.


The down-converter includes a bypass path to minimize cable swapping when the mixer is not required. The bypass path includes a user-selectable filter bank and low noise amplifier for signal conditioning purposes. For harmonic measurement applications, a bank of high pass filters (HPF) is available to reject the fundamental signal and provide better dynamic range. The down-converted signal is passed through 5GHz intermediate frequency (IF) filter for spurious rejection prior to output from the module.


Like its counterpart, the up-conversion path includes bypass capability and several signal conditioning options. Self calibration of the instrument is possible using the built-in loop back signal in the up-converter.


  • General purpose Up/Down Conversion functions
  • Single-Slot 3U PXIe Module
  • Operating Conditions: 15 to 45 C


Rx Down-Conversion Path

  • Input Frequency: 6 – 18 GHz
  • Output center frequency: 5.1 GHz
  • Maximum Input Power: +20 dBm
  • Maximum Harmonic Input Power: -25 dBc
  • Instrument Generated Harmonic Distortion (@20 dBm):
    • 2nd: -80 dBc
    • 3rd: -75 dBc
  • IF Filter Bandwidth: 200 or 1500 MHz
  • Calibrated Amplitude Accuracy: 1 dB
  • Noise Figure @6 GHz:
    • 11 dB with Pre-Amplifier
    • 25 dB without Pre-Amplifier
  • Noise Figure @18 GHz:
    • 21 dB with Pre-Amplifier
    • 36 dB without Pre-Amplifier
  • Gain (@6 GHz):
    • 5 dB with Pre-Amplifier
    • -11 dB without Pre-Amplifier
  • Gain (@18 GHz):
    • 17 dB with Pre-Amplifier
    • -0 dB without Pre-Amplifier


Receive Mixer Bypass Path

Allows instrument to remain in the signal path and provides some optional signal conditioning for frequencies less than 6 GHz.


Transmit Up-Conversion Path

Allows signals to be conditioned and optionally mixed up to a higher frequency.

  • Input Frequency range: 400 MHz – 6 GHz
  • Output Frequency range: 6 – 18 GHz
  • Maximum Output Power (rms): 10 dBm max
  • Fundamental Rejection: 30 dB min
  • Calibrated Amplitude Accuracy: 1 dB
  • Gain (@6 GHz): 4 dB
  • Gain (@18 GHz): -8 dB


Transmit Bypass Path

Conditions VST signals by filtering out unwanted harmonic and spurious content.

  • Frequency Range: 10 MHz – 6 GHz
  • Insertion Loss : 10 dB max
  • Rejection : 30 dB min
  • Frequency Range: 10 MHz – 6 GHz
  • Insertion Loss : 10 dB max


Instrument Control

  • 32/64 bit IVI Compatible Driver