Chapter 4 - Using the Data Processing Feature

Data Processing Feature

Using the Measurement Calculator / Register Math Function.

Use this option to perform arithmetic operations on the measurement registers. For example if you make measurements on one antenna and wish to compare the results to another antenna at each point of rotation and each frequency. Or if you have a calibrated reference antenna an wish to normalize additional measurements to the max or min value of the reference antenna. Remember all measurement data is linear so you may want to “LOG” the data before doing math. If you select MAX or MIN then all measurement elements will be replaced with MAX or MIN. This creates a normalization reference if you do your math correctly.

Register Math / Calculator Screenshot

Understanding the Register Math Functions

Measurement data is initially stored in the Active registerwhen you leave the main software page and enter the advanced processing section. When you proceed to the Data Processing Feature you have a choice of 4 additional registers in which to store Reg0.

The measurement format is: dataReg0-4[Mag,Phase,(Hpos,Vpos),0/1,freq]

Each time you press the Reg calculator = sign the results are save to the Active Register. You can then save those results to any one of the 4 original Regs. Be sure to have saved the original to disc as it will be over written.

Math Functions

Linear : When highlighted the Reg# to the right is to be used as S21 in vector format Arithmetic is performed using vector components

LinearMag : When highlighted the Magnitude of Reg # to the right is to be Logged (dB) and used as a scalar array in all arithmetic operations. The angle information is remains in the original Reg# but is lost in the calculator.

LOGmag: When highlighted the Reg# to the right is to be used as 10LOG(S21^2) in scalar format The frequency S21 angle information remains in the original Reg # but is lost in the calculator.

^2 : When highlighted the Reg# to the right is to be used in complex format and squared

SQRT : When highlighted the Reg# to the right is to be used complex format ^(1/2)

Max : When highlighted the Reg# to the right Maximum Linear value is to be used in all matrix arithmetic. This provides a good way to normalize measurements. The frequency S21 angle information remains in the original Reg# but is lost in the calculator.

Min : When highlighted the Reg# to the right Minimum Linear value is to be used in all matrix arithmetic. This provides a good way to normalize measurements. The frequency S21 angle information remains in the original Reg# but is lost in the calculator.

Constant :> Use the constant option to +-/* a constant to the first register set (left) This is useful when you wish to add level shifts such as 3dB for HV polarization measurements not accounted for anywhere else.

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HP 6000 Using the Measurement Calculator / Register Math Function, Register Math / Calculator Screenshot, Math Functions