Agilent Technologies 8510 S11 A,B,C and S22 A,B,C, Forward transmission match and thru, Isolation

S11 A,B,C and S22 A,B,C

S11 A, B,C and S22 A,B,C correspond to the S11 and S22 reflection calibrations for port 1 and port 2 respectively. These three classes are used by the Agilent 8510 to solve for the systematic errors; directivity, source match, and reflection tracking. The three classes used by the 7-mm cal kit are labeled “short,” “open,” and “loads.” “Loads” refers to a group of standards which is required to com- plete this standard class. A class may include a set of standards of which there is more than one acceptable selection or more than one standard required to calibrate the desired frequency range.

Table 2 contains the class assignment for the WR- 62 waveguide cal kit. The 1/8 λ offset short (stan- dard #1) is assigned to S11A. The 3/8 λ offset short (standard #2) is assigned to S11B. The matched load (standard #3) is assigned to S11C.

Forward transmission match and thru

Forward Transmission (Match and Thru) classes correspond to the forward (port 1 to port 2) trans- mission and reflection measurement of the “delay/thru” standard in a FULL 2-PORT or ONE- PATH 2-PORT calibration. During measurement calibration the response of the “match” standard is used to find the systematic Load Match error term. Similarly the response of the thru standard is used to characterize transmission tracking.

The class assignments for the WR-62 waveguide cal kit are as follows. The thru (standard #4) is assigned to both FORWARD TRANSMISSION and

FORWARD MATCH.

Reverse transmission match and thru

Reverse Transmission (Match and Thru) classes correspond to the reverse transmission and reflec- tion measurement of the “delay/thru” standard. For S-parameter test sets, this is the port 2 to port 1 transmission path. For the reflection/transmission test sets, the device is reversed and is measured in the same manner using the forward transmission calibration.

The class assignments for the WR-62 waveguide cal kit are as follows. The thru (Standard #4) is assigned to both REVERSE TRANSMISSION and

REVERSE MATCH.

Isolation

Isolation is simply the leakage from port 1 to port 2 internal to the test set.

To determine the leakage signals (crosstalk), each port should be terminated with matched loads while measuring S21 and S12.

The class assignments for forward and reverse iso- lation are both loads (standard #3).

Frequency response

Frequency Response is a single class which corre- sponds to a one-term error correction that charac- terizes only the vector frequency response of the test configuration. Transmission calibration typi- cally uses a “thru” and reflection calibration typi- cally uses either an “open” or a “short.”

Note

The Frequency Response calibration is not a sim- ple frequency normalization. A normalized response is a mathematical comparison between measured data and stored data. The important dif- ference is, that when a standard with non-zero phase, such as an offset short, is remeasured after calibration using Frequency Response, the actual phase offset will be displayed, but its normalized response would display zero phase offset (meas- ured response minus stored response).

Therefore, the WR-62 waveguide calibration kit class assignment includes standard #1, standard #2, and standard #4.

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