FOCUS MICROWAVES GROUP

Noise Measurements

Wideband noise parameters extraction

V01/17powered by FOCUS MICROWAVES

NoiseNoise measurements allow the determination of the four Noise Parameters of a device (transistor).
Noise Parameters: These are four numbers that fully describe the noise behaviour of an active or passive device(twoport) at a given frequency. For practical reasons weuse the following quantities as Noise Parameters:•••

Stability Circle

Minimum Noise Figure (Fmin): This is the smallest
Noise Figure that the device can reach at a givenfrequency and bias, if it is optimally matched at thesource.
Equivalent Noise Resistance (Rn): This is a number
with the dimension Ohm that indicates how fast theNoise Figure increases when we mismatch the input(source).
Optimum Noise Reflection Factor (Γopt ), is often used also as Optimum Admittance Yopt: Is thesource admittance required for the DUT to perform
Fmin ; (Yopt=Gopt+jBopt), 2 parameters.

The Noise Figure does not depend on the Load impedance presented to the device . It only depends on theSource Impedance. There exist a simple relation betweenthe four Noise Parameters:
Noise Figure F(Ys) = Fmin + (Rn/Gs)*| Ys - Yopt|2
where Ys = Gs +jBs. This is the equation of a set of isometric circles on the Smith Chart (Noise Circles) for which
the value of the Noise Figure is the Level on each circle.

Noise Circles & Instability Regions

This Circle Representation is only possible because theNoise behaviour of transistors is a Small Signal Phenomenon.

S112

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Noise Measurements Using PNA-X
Focus’ noise parameter extraction routines
leverage the PNA-X’s unique implementationof the cold-source noise figure measurement
technique. This specific technique requires anoise source to determine the kBG (gain-bandwidth constant) of the system and a passive mechanical tuner is used to characterize the noise
receiver across both the impedance and frequency space. This step is imperative to obtainfully vector-source-corrected measurements. ARF down conversion stage might be required if
the frequency of noise measured exceeds thereceiver’s bandwidth. Focus offers noise modules which support down conversion for optimal
speed and performance.

Noise Measurements Using ZVAA new and smart method enables the extractionof the four noise parameters of an active device
with a Rohde & Schwarz vector network analyzer.
The rather simple and straight forward approach
does not require a calibrated noise source witha given ENR (Excess Noise Ratio). Instead, thetechnique uses the CW signal from the VNA
source. Using different detectors it measuresthe ‘signal’ respectively and the ‘signal + noise’
output power of the DUT. Combined with a Focus wideband fundamental tuner and advanced
characterization software, the user can extract
the four s-parameters and noise parameters ina single sweep.

Noise Measurements with Noise Receiver

Keysight X-Series

The R&S® FSV/FSWLegacy Noise Receivers

Focus’ system architecture supports
all of the X-series analyzers. Keysight’s N9069A/W9069A noise figure measurement application uses
the Y-factor method to calculate
the noise figure.

Focus also supports R&S’ K30 option which plots Noise figure andgain measurements based on Y-factor method. The FSV/FSW calibrated internal pre-amp is a great alternative to external LNAs.

Considered as an industry standardfor decades the soon to be discontinued N897XA family of noise figure
analyzers is still supported by Focus’
FDCS measurement suite.
www.focus-microwaves.com

3Model Specifications
Tuner Models: CCMT-XXYY(Y): XX=Fmax (in GHz); YY=Fmin (in x 0.1GHz)

Popular CCMT Tuners
Model

Frequency

VSWR

Connector

CCMT-308
CCMT-708
CCMT-808
CCMT-1808
CCMT-710
CCMT-2110
CCMT-2610
CCMT-716
CCMT-1816
CCMT-1818
CCMT-2620
CCMT-3620
CCMT-5010
CCMT-5020
CCMT-4030
CCMT-5080
CCMT-67100
CCMT-110100

0.8-3GHz
0.8-6.5GHz
0.8-8GHz
0.8-18GHz
1-7GHz
1-21GHz
1-26.5GHz
1.6-6.5GHz
1.6-18GHz
1.8-18GHz
2-26.5GHz
2-36GHz
1-50GHz
2-50GHz
3-40GHz
8-50GHz
10-67GHz
10-110GHz≥12:1 (typ. 15:1)≥12:1 (typ. 15:1)≥20:1≥10:1 (typ. 15:1)≥10:1 (typ. 12:1)≥10:1 (typ. 12:1)≥10:1 (typ. 12:1)≥12:1 (typ. 20:1)≥10:1 (typ. 15:1)≥10:1 (typ. 15:1)≥10:1 (typ. 12:1)≥10:1 (typ. 12:1)≥10:1≥10:1 (typ. 12:1)≥10:1 (typ. 12:1)≥12:1 (typ. 15:1)≥10:1 (typ. 15:1)≥8:1

APC-7, 7/16, N T.
APC-7, N Type
APC-7, N Type
APC-7, N Type
APC-7, N Type
2.9mm
2.9mm
APC-7, 7/16, N T.
APC-7, N Type
APC-7, N Type
3.5mm
2.9mm (K®)
2.4mm
2.4mm
2.9mm (K®)
2.4mm
1.85mm1.0mm

Input Noise Module
Model

Frequency

Connector

Insertion Loss

VSWR

INM-2600
INM-4000
INM-5000
INM-6700

up to 26.5GHz
up to 40GHz
up to 50GHz
up to 67GHz

3.5mm
2.9mm
2.4mm
1.85mm0.80dB
0.91dB
0.99dB
1.12dB

1.60
1.80
1.80
1.90

Output Noise Module4Model

Frequency

Connector

ONM-2600
ONM-4000
ONM-4000-DC
ONM-5000
ONM-5000-DC
ONM-6700
ONM-6700-DC

up to 26.5GHz
up to 40GHz
up to 40GHz
up to 50GHz
up to 50GHz
up to 67GHz
up to 67GHz

3.5mm
2.9mm
2.9mm
2.4mm
2.4mm
1.85mm
1.85mminfo@focus-microwaves.com

Downconverter▼▼▼

Minimum Gain (dB)Maximum VSWR

29
30 for ≤26.5GHz, 29 for 26-40GHz
30 for ≤26.5GHz, 29 for 26-40GHz
27 for ≤26.5GHz, 27 for 26-40GHz, 28 for 40-50GHz
27 for ≤26.5GHz, 27 for 26-40GHz, 28 for 40-50GHz
29 for ≤26.5GHz, 28.5 for 26-40GHz, 28 for 40-50GHz, 21 for 50-65GHz
29 for ≤26.5GHz, 28.5 for 26-40GHz, 28 for 40-50GHz, 21 for 50-65GHz

1.8:1
2.1:1
2.1:1
2:1
2:1
3:1
3:1

+1 514 684 4554

www.focus-microwaves.com