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Is there an outline to achieving a simplified mixer conversion loss measurement on the ENA?

(SUPPORTED MODELS IN BOLD: E5071C E5072A E5070B/71B E5070A/71A E5061A/62A E5061B E5063A E5091A E5092A)

Simplified mixer conversion loss measurement details for the ENA are noted below. Option 008, Frequency offset, is required for mixer measurements utilizing these analyzers. The outline below does not include any form of error correction measurement enhancements.

Details 

E5071C running firmware version A.09.10
Mixer Input frequency 250MHz to 280MHz (i.e. swept RF)
Local Oscillator (LO) frequency 190MHz (i.e. fixed LO)
Intermediate Frequency (IF) 60MHz to 90 MHz (i.e. swept IF)

As noted this specific mixer test is considered a "swept RF, fixed LO, swept IF mixer test configuration". The fixed LO configuration does not require control of the LO source.

To ensure optimum performance if the LO source has an accessible 10MHz reference, then the 10MHz time bases of the LO and the ENA should be connected together. Utilize the more accurate 10MHz reference as the "reference source input".

Instrument Setup

1) Preset the analyzer

  • Preset (hard key – HK) – OK (soft key – SK)

2) Set Port 1 swept RF start (250MHz) and stop (280MHz) frequencies

  • Start (HK) – 2 (HK) – 5 (HK) – 0 (HK) – M/u (HK)
  • Stop (HK) – 2 (HK) – 8 (HK) – 0 (HK) – M/u (HK)

3) Set analyzer for Frequency Offset mode

  • Sweep Setup (HK) – Frequency Offset (SK) - Frequency Offset = ON (SK)

4) Port 1 (port 1 is the stimulus for the swept RF mixer input)

  • Sweep Setup (HK) – Frequency Offset (SK) – Port 1 (SK)
  • Confirm the Start frequency = 250MHz
  • Confirm the Stop frequency = 280MHz
  • Return (SK)

5) Port 2 (port 2 is considered the input, as output from the mixer’s swept IF output)

  • Sweep Setup (HK) – Frequency Offset (SK) – Port 2 (SK)
  • Start (SK)
  • 6 (HK) – 0 (HK) – M/u (HK) – {i.e. set to 60MHz}
  • Stop (SK)
  • 9 (HK) – 0 (HK) – M/u (HK) – {i.e. set to 90MHz}

6) External Source (Fixed LO frequency)

  • Sweep Setup (HK) – Frequency Offset (SK) – External Source (SK)
  • Start (SK)
  • 1 (HK) – 9 (HK) –0 (HK) – M/u (HK) – {i.e. set to 190MHz}
  • Stop (SK)
  • 1 (HK) – 9 (HK) –0 (HK) – M/u (HK) – {i.e. set to 190MHz}
  • Ensure Control (SK) = OFF
  • LO Frequency (SK) = ON

7) Configure S21 Measurement (conversion loss) and stimulus to -40 dBm

  • Meas (HK)
  • S21 (SK)
  • Sweep Setup (HK) – Power (HK) -4 (HK) - 0 (HK) - x1 (HK). This is the power level of analyzer source 1 into the mixer under test (MUT)

The displayed trace is a measure of the MUT conversion loss in decibels (dB). Adjust the LO power and observe the effects on conversion loss. As noted previously this is a non-corrected mixer conversion loss measurement. Scalar or Vector correction can be achieved thru the use of the de-embedding feature. For additional details refer to Chapter 8 Frequency-Offset Measurement (Option 008) of the "Keysight E5070B/E5071B ENA Series RF Network Analyzers User’s Guide". Also refer to the ENA Series RF Network Analyzers Application Note 1463-7 Accurate Mixer Conversion Loss Measurement Techniques.