Third Order Intermodulation Distortion Performance Test

This test applies to the following models:

This test measures the Third-Order Intermodulation (TOI) Distortion produced by two discrete signals, and computes the Third Order Intercept (TOI) point.

TOI is tested above 26.5 GHz on the following models:

Two signals separated by 100 kHz are combined in a directional bridge or directional coupler (for isolation) and are injected into the analyzer input. The spectrum analyzer measures the amplitude of the lower and upper distortion products. TOI is computed using the higher (worst case) of these two products.

Below 3.6 GHz low pass filters are used to attenuate the source second harmonic. The harmonic is filtered so it does not create a false failure. Above 3.6 GHz the internal YTF filters the source harmonic.

The filtered source is turned on and the signal level is measured at the splitter output port with a power meter. The filtered source amplitude is measured on the analyzer. The unfiltered source is turned on and its amplitude is measured on the analyzer using the analyzer’s delta-marker feature. The amplitude of the distortion product is then measured relative to the unfiltered source amplitude.

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Required Test Equipment

Test Equipment

Recommended Model Number

Microwave Signal Generator #1 and
Microwave Signal Generator #2

PSG Models
(see equipment list)

Power Meter

N1914B

Microwave Power Sensor

  • Options ≤ 526

N8485A 

Microwave Power Splitter

  • Options ≤ 526

11667B

Millimeter Power Sensor

  • Options > 526

N8487A CFT

Millimeter Power Splitter

  • Options > 526

11667C

Directional Bridge

86205A 

Directional Coupler

87300C

Millimeter Directional Coupler

  • For N9030A/B and N9040B options > 526, and N9010N

87301C

10 dB Fixed Attenuator, 3.5 mm (f) to 3.5 mm (m)

8493C Option 010

10 dB Fixed Attenuator, 2.4 mm (f) to 2.4 mm (m)

  • For N9030A/B and N9040B options > 526, and N9010N

8490D Option 010

BNC Cable

  • 2 required

8120-1840 

Coaxial Cable, 3.5 mm

  • 3 required

11500E

50 MHz Low Pass Filter

  • Not required for EXA

Telonic Berkeley TLA 50-5AB2

1.8 GHz Low Pass Filter

  • 2 required

RLC L-1636

3.5 mm (f) to 3.5 mm (f) adapter 

  • 2 required
  • For 3.5 mm sources

83059B 

BNC (m) to SMA (f) adapter

1250-1700

Type-N (m) to Type-N (m) adapter

1250-1475

Type-N (m) to BNC (f) adapter

1250-1476

Type-N (m) to 3.5 mm (m) adapter

  • 2 required

1250-1743

Type-N (m) to 3.5 mm (f) adapter 

  • 2 required

1250-1744

3.5 mm (m) to 3.5 mm (m) adapter

  • 2 required

83059A

2.4 mm (f) to 3.5 mm (f) adapter

  • 2 required
  • For 2.4 mm sources

11901B 

Connection Setups

Power Meter Calibration


 

Third Order Intercept Distortion Low Band Test Setup
(50 MHz Low Pass Filter)

 

Not tested on the EXA.

 

 

Third Order Intercept Distortion Low Band Test Setup
(1.8 GHz Low Pass Filter)

 

Third Order Intercept Distortion High Band Test Setup

 

Third Order Intercept Distortion High Band Test Setup > 25 GHz
(For N9030A/B and N9040B options > 526, and N9010N)