Most Common Types of VNA Calibration Procedures

This discussion, while listing all common calibration techniques, is primarily concerned with those which readily apply to frequencies from 50 to 325 GHz. The comments are specifically directed toward those calibration procedures which best suit millimeter wave waveguide and wafer probe applications.

Acronym	Description	Comments	Applications
Two Port Calibrations
1) LRL	Line / Reflect (short) / Line	Most accurate	D	F,H,J
2) LRM	Line / Reflect (short) / Match (Load)	Easier to use	D	E,G,J
3) LRA	Line / Reflect (short) / Attenuation		D	J
4) TRL	Thru / Reflect (short) / Line	Very accurate	D	K
5) TRM	Thru / Reflect (short) / Match (Load)	Easier to use	D	E,G,J
6) TRA	Thru / Reflect (short) / Attenuation		D	J
7) TSD	Thru / Short / Delay		D
8) OOLsT	Offset Short / Offset Short / Load (sliding) / Thru		A,C	E,G,J
9) OOLfT	Offset Short / Offset Short / Load (fixed) / Thru		D	E,G,J
10) SSLsT	Offset Short / Short / Load (sliding) / Thru	Same as 8)	A,C	E,G,J
11) SSLfT	Offset Short / Short / Load (fixed) / Thru	Same as 9)	D	E,G,J
12) OSLfT	Open / Short / Load (fixed) / Thru	Simple	A,B	E,G,J
13) OSLsT	Open / Short / Load (sliding) / Thru	More accurate	A	E,G,J
One Port Calibrations
14) OOLf	Offset Short / Offset Short / Load (fixed)		D	E,G,J
15) OOLs	Offset Short / Offset Short / Load (sliding)	Same as 16)	A,C	F,H,J
16) SSLs	Offset Short / Short / Load (sliding)	Accurate	A,C	E,G,K
17) SSLo	Offset Short / Short / Load (fixed) / Offset Load (fixed)	Most accurate	D	K
18) OSLf	Open / Short / Load (fixed)	Simple	A,B	E,G,J
19) OSLs	Open / Short / Load (sliding)	More accurate	A	E,G,J
20) SSS	Three different shorts	(180 deg. difference across the three)	D	J
Applications:
Media:	A) coax, B) wafer, C) waveguide, D) universal
CAL Procedure:	E) supported by Anuitsu Lightning G) supported by Wiltron 360 J) supported by Agilent/HP 8150	F) preferred for Anuitsu Lightning H) Preferred for Wiltron 360 K) preferred for Agilent/HP 8510
Notes:
Short vs Offset Short:	Both specify two shorts offset with 1/4 wavelength difference
Thru vs Line:	Thru is a connection of zero length using the waveguide section normally attached to the test set. Line inserts an additional waveguide section of precise length.
Load (fixed) or Match:	Procedure assumes a load return loss of >40 dB for a good calibration

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