Freq Resp Above 250 kHz Option BBA Performance Test

This test applies to the following models with Option BBA:

The BBIQ Verification tests rely on the BBIQ Front Panel Alignment being run within 8 hours of running a verification test. If the alignment timestamp is greater than 8 hours from the current time, TME will run the BBIQ alignment. If the time difference between the DUT and the TME station clock is more than 8 hours, then TME will get stuck in an endless BBIQ alignment loop. To prevent this from happening, the DUT clock should be set to the local time. At the end of the adjustment cycle, set the DUT clock back to the customer's local time.

The Baseband IQ (BBIQ) hardware is a separate measurement path from the signal analyzer RF path. The BBIQ path is controlled through the IQ Analyzer Mode. The BBIQ hardware has four different input ports (or channels):

  • I (unbalanced)

  • I-Bar (balanced)

  • Q (unbalanced)

  • Q-Bar (balanced)

Each input port has 4 different amplitude ranges:

  • 1 Volt Peak (+10 dBm)

  • 0.5 Volts Peak (+4 dBm)

  • 0.25 Volts Peak (-2 dBm)

  • 0.125 Volts Peak (-8 dBm)

Each input has two impedance choices: 50 Ohm and 1 Meg Ohm. There are potentially 32 different Input/Range/Impedance test variants that need to be tested.

Frequency Response is defined as the amplitude difference at a test frequency compared to the reference amplitude at 250 kHz. The Frequency response will be tested to 10 MHz, 25 MHz, or 40 MHz depending on the IF bandwidth option. The IF bandwidth will follow the Basebox IF bandwidth with the exception of Option S40. Option S40 is a 40 MHz IF Bandwidth for the BBIQ Path.

This test will depend on the BBIQ IQ Cable Cal. The IQ Cable Cal is a frequency response calibration that is done manually on the signal analyzer. If the time since a IQ Cable Cal has been performed is more than 8 hours, the user will be prompted to perform an IQ Cable Cal.

 

BBIQ Frequency Response is described as a nominal specification. Generally nominal parameters are not tested. Frequency Response is tested because there is a minimum level of functionality that needs to be guaranteed. This level of functionality is especially true in the case of a field retrofit.

 

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Required Test Equipment

Test Equipment

Recommended Model Number

Function Generator

33622A

Power Meter

N1914B

RF Power Sensor

N8482A

Power Splitter

11667A 

Type-N (m) Termination

909A Option 012

BNC (m) Termination

1250-0207

BNC Cable
(4 ft, 2 required)

8120-1840 

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

1250-1473

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

1250-1476

Type-N Tee

1250-0559

Connection Setups

In the following setups, cables are designated as solid lines and direct connections are designated as dashed lines.

Power Meter Calibration



For 50 ohm impedance setups, :

Freq Resp Above 250 kHz Option BBA (50 ohm) Test Setup

 

Freq Resp Above 250 kHz Option BBA (50 ohm)
I-Bar Input Test Setup

Freq Resp Above 250 kHz Option BBA (50 ohm)
Q-Bar Input Test Setup

 

For 1 Meg ohm impedance setups, :

Freq Resp Above 250 kHz Option BBA (1 Meg ohm) Test Setup

 

Freq Resp Above 250 kHz Option BBA (1 Meg ohm)
I-Bar Input Test Setup

 

Freq Resp Above 250 kHz Option BBA (1 Meg ohm)
Q-Bar Input Test Setup