Anritsu manual 1-12, K Factor, General Information, ME7840A OMM, Software, Description

GENERAL INFORMATION K FACTOR

S22) are not desired, then a circulator is not required. Instead, a through line should be connected between connectors C1 and C2 (Figure 1-5). The MS4782A is shipped from the factory with this through line in place.

1-10K FACTOR	K factor is a parameter which is sometimes used to indicate the stability
	of an amplifier. K factor is a function of all four S parameters and is de-
	fined by the formula
		1￿	S		2 ￿		S	2 ￿	￿	2
	K ￿		11				22
				2		S11 S21

Where

￿= S11S22￿S12S21

The necessary and sufficient condition for unconditional stability is that

K>1 and ￿ ￿ 1.

K factor is available as the sixth choice in the S parameters menu (first five choices are: S11, S22, S21, S12 and ALL). The same conditions and setup as S-parameter measurements including a full 12-term calibration applies to this measurement. The result is “dynamic” meaning that the above formula is applied at each point for each sweep as the S parame- ters are reported to the PC over the GPIB.

1-11ADAPTIVE P STOP Adaptive P stop lets users enter a gain compression value at which the program will adjust the final Pin value during a power sweep. For exam- ple, if user sets 3 dB P-stop, the program commands the execution of one sweep, find Pin value where 3 dB gain compression occurs, back up 1 in- crement, and reset this as the upper bound of the power sweep.

1-12

1-13

SOFTWARE	The ME7840A software exhibits an open architecture that has been de-
DESCRIPTION	veloped using standard C++ and Visual Basic languages. The software is
	compiled as an Active X exe module.
	The software resides in the System Controller (PC), and communicates
	with the Direct Receiver Access (DRA) Scorpion￿ Vector Network Mea-
	surement System (VNMS) via the GPIB bus. Optionally, the ME7840A
	software can also interface with additional GPIB capable test equipment,
	such as a multimeter or a power meter.
TEST EXECUTIVE	The Test Executive is an optional layer of test management software. The
	ANRITSU measurement and display software does not require a separate
	Test Executive, even though it can operate in conjunction with one such
	as the National Instruments TestStand or customer’s proprietary Test
	Executive. In the absence of a separate test executive, the ANRITSU soft-
	ware can be operated on a stand-alone basis or can be called directly by a
	Microsoft Windows 95/98/2000 or NT program such as Word, Excel or Ac-
	cess that supports Visual Basic function calls.

ME7840A OMM 1-9