Agilent Technologies e4419b, e4418b Pmeas = fVcomp,V1,V0,R,CF,Ms, Figure B-1 Measurement Setup

Measurement Uncertainty Analysis – Power Reference Level Test

Measurement Introduction

where,

Ps is the reflection coefficient of the source (i.e. the DUT) and Pd is the reflection coefficient of the 8478B detector.

Hence,

Pmeas = f(Vcomp,V1,V0,R,CF,Ms)

Consider the measurement setup that exists in Figure B-1

POWER

REF

DUT

PS

8478B

Pd

432A Power Meter

Figure B-1: Measurement Setup

Po is the total power output from the DUT. Of this power a proportion related to Pd is reflected back towards the source. The power subjected on the 432 would be:

2 Po1 – Pd 

But because a proportion of this total power related to Pd has been reflected Ps will again cause a reflection giving:

Po(1±PsPd)2

So the total power incident or measured by the 432 Power meter is given by:

Po1 – Pd2⁄ (1±PsPd)2

Note	In all cases Pd is extremely small therefore Pd² terms tend to zero leaving.
	Agilent E4416A/E4417A	Service	Guide	B-3