This section is for performing most functions regarding Noise Figure. Noise Figure is a figure of merit of Signal to Noise and the performance of devices and their effect on this signal to Noise ratio or the total noise power.

This screen is used for converting Noise and Noise Power
Units and Noise Measure. For the left side enter the Device Noise Figure in dBF
and the Device Gain in dB and press the “Calculate” button to figure the
Noise Measure. For the right side enter any one Noise value in Noise Figure in
dB, Noise Temperature in Kelvin or Noise Factor and it will figure
the remaining two conversions. I defaulted the Ambient Temperature to 290K or
27C for ease. This temperature is used to figure the temperature of the noise
source. Press **Calculate** to compute and display. **Clear** to reset and reenter value to retry and **Close** to Quit.

Figure 103 – Noise Figure Conversions and Noise Measure

This screen is used figuring the Noise Power of a source.
For the left side enter the Temperature in Kelvin, the Bandwidth in Hz, the
Impedance in Ohms, Device Noise Figure in dBF and the Device Gain in dB and
press the “Calculate” button to figure the Noise Power in dBm and Watts and
also in Vrms. I defaulted the Ambient Temperature to 290K or 27C and the
Bandwidth to 1Hz and the Impedance to 50 Ohms for ease, but the user can change
if desired. Press **Calculate** to
compute and display. **Clear** to reset
and reenter value to retry and **Close**
to Quit.

Figure 104 – Noise Figure Noise Source

This function set calculates the Noise Figure in dBF, the
DANL/ANL Displayed Average Noise level or Average Noise Level and the Tangential
Sensitivity. Enter the Temperature in Kelvin, the bandwidth in Hertz and one of
the three DANL, Noise Figure or Tangential Sensitivity. It will compute the
missing factor. If the DANL/ANL check box is checked it computes to/from DANL
and unchecked it computes to/from ANL. In the case below I entered the
temperature, bandwidth and checked the DANL box and entered the DANL of
–88dBm/Hz. It calculated the Noise figure and Tangential Sensitivity of the
receiver. Press **Calculate** to compute
and display. **Clear** to reset and
reenter value to retry and **Close** to
Quit.

Figure 105 – Noise Figure DANL/ANL to NF and TSS

This screen is used figuring the Input Noise Power to a Noise Figure Meter or other receiver like a Spectrum Analyzer for instance. It can also be used to back calculate the noise figure of a device given the temperature, gain and Noise Power at Resolution Bandwidth (Bw>1Hz) or Spectral Noise Density or Noise Marker value (Bw=1Hz). This calculation is useful for performing “Cold Power” noise figure measurement vs a Hot/Cold Noise Figure measurement such as with a Noise Figure Meter or the Spectrum Y Factor method. If using the cold power method be sure to clear the value in the DUT NF test box, so it detects the missing value to calculate and add the Input Noise Power value. It senses the missing value and calculates it.

Enter the Temperature in Kelvin, the Bandwidth in Hz, the ENR Excess noise Ratio in dB, Pre-Amp Gain in dB, Device Noise Figure in dBF and the Device Gain in dB and press the “Calculate” button to figure the Total Noise Power in dBm/Hz. I default the Ambient Temperature to 290K or 27C and the Bandwidth to 1Hz for ease, but the user can change if desired. Press “Clear” to clear and start over and “Close” to quit the screen.

This screen can also be used to back calculate the device Noise Figure for “Cold Power” measurements. That is the Output Noise Power of a device is dependent on the device gain and Noise Figure. If the Gain is known (measured) you can then back calculate the Noise Figure from the Output Noise Power.

Figure 106 – Noise Figure input Noise Power

This screen is used for figuring the Noise Figure and Gain
of a device using the Y-Factor method. Measure the Noise On and Noise Off power
ratio to figure the Noise Figure Using a Spectrum Analyzer, Power Meter or other
receiver. Enter the Temperature in Kelvin, the Bandwidth in Hz, Excess Noise
Ratio (ENR) of the Noise Source in dB, Input Loss in dB, Noise Power On and Off
in dBm and press the **Calculate** button
to figure the Noise Figure Power in dBF and Gain in dB. I default the Ambient
Temperature to 290K or 27C and the Bandwidth to 1Hz for ease, but the user can
change if desired. **Clear** to reset and
reenter value to retry and **Close** to
Quit.

Figure 107 – Noise Figure Y Factor

This screen is used for figuring the Cascaded or Embedded
or DeEmbeded Noise Figure of a system. Enter the Input Loss before DUT in dB,
the First Stage Gain and Noise Figure and the Second Stage Noise Figure and
press the **Calculate** button to figure
the F21 Noise Figure in dBF. In addition you can work the equation backwards to
figure what F1 would be needed to get a specific F21 and F2 for the system. I
default the Ambient Temperature to 290K or 27C for ease, but the user can change
if desired. **Clear** to reset and
reenter value to retry and **Close** to
Quit.

Figure 108 – Noise Figure DeEmbedded/Embedded Noise

This screen is used for figuring the Excess Noise Ratio (ENR)
correction for non-standard ambient temperature and input loss. Enter the
Temperature in Kelvin, ENR Excess Noise Ratio of the Noise Source in dB, Input
Loss in dB and press the **Calculate**
button to figure the Corrected ENR in dB. I default the Ambient Temperature to
290K or 27C for ease, but the user can change if desired. **Clear** to reset and reenter value to retry and **Close** to Quit.

Figure 109 – Noise Figure ENR Offset for Loss and Temperature

Enter the System Total Noise Figure (Device 1 and 2), DUT
Gain, DUT Gain Uncertainty and the Noise Figure Meter Noise Figure. Press **Calculate**
to perform the calculation and get the Upper and Lower Limit of the DUT (Device
1) Noise Figure measurement. **Clear** to
reset and reenter value to retry and **Close**
to Quit.

Figure 141 – Noise Figure Error Gain Uncertainty

Figure 142 – Noise Figure Error ENR Error

Enter the Noise Source S11 or Input Return Loss, the DUT
Noise Figure, DUT Gain, DUT S11 Input and S22 Output Return Losses. I have some
initial estimates of the Known Uncertainties defaulted for the operators help.
These particular values are the ones I found for the Agilent instruments. Press **Calculate**
to perform the calculation and get the Calculated Uncertainties: System Total
Noise Figure NF12, Noise Figure Meter NF2, DUT Gain and finally DUT Noise
Figure. Press **Clear** to clear all
variables and redo and **Close** to quit
the screen.

Figure 143 Noise Figure Error System Noise Error

This section computes the available gain for the loss
correction factor for input noise test systems from the source, load and input
network S-Parameters. Enter the values as shown in Figure 137 and Press **Calculate**
to compute, **Close** to quit and **Clear** to clear the value to retry.

Figure 144 – NF Available Gain/Loss