Noise Temperature to Noise Figure Converter

Convert noise temperature (K) to noise figure (dB) using the Friis formula. This calculator is useful for RF system design and analysis.

Input Parameters

Calculation Results

Noise Figure (dB)

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Calculation Formula

NF(dB) = 10 * log[1 + (T_noise / T_system)]

Where:
NF(dB) - Noise Figure in decibels
T_noise - Noise Temperature in Kelvin
T_system - System Reference Temperature (typically 290K)

Noise Temperature to Noise Figure Converter Calculator Usage Guide

Learn how to use the Noise Temperature to Noise Figure Converter calculator and its working principles

How to Use This Calculator

  1. Enter the noise temperature of your system in Kelvin (K). This is typically the sum of the antenna noise temperature and any amplifiers' equivalent noise temperature.
  2. Enter the system reference temperature. The standard value is 290K, which represents the noise temperature of a warm resistor at standard temperature.
  3. Click the "Calculate" button to convert the noise temperature to noise figure in decibels (dB).
  4. The calculator will display the noise figure in dB and show the formula used for the calculation.

Working Principle

The calculator uses the Friis formula to convert noise temperature to noise figure:

NF(dB) = 10 * log[1 + (T_noise / T_system)]

This formula relates the noise temperature (T_noise) to the noise figure (NF) in decibels, where T_system is the system reference temperature. The noise figure is a measure of the degradation of signal-to-noise ratio (SNR) caused by components in a signal chain.

Applications

This calculator is particularly useful in RF engineering for:

  • Designing communication systems with minimum noise performance requirements
  • Comparing different components based on their noise characteristics
  • Calculating the overall noise performance of cascaded systems