# Microwave Calculator

The MicroWave calculator aims to help calculate the errors in your microwave measurements. It consists of Directivity Error Calculator, Mismatch Error Limit Calculator, and Ratio-to-dB Calculator.

## Directivity Calculator

The Directivity Error Calculator shows the accuracy of a reflection measurement of unknown impedance based upon the directivity of the coupler used for the measurement. It is also a convenient way to convert a reflection coefficient to an equivalent standing wave ratio (SWR), return loss, or mismatch loss.

## Mismatch Error Limit Calculator

The Mismatch Error Limit Calculator shows the potential error (or uncertainty) in a transmission measurement due to imperfect source match and load match. It can also be used in a reflection measurement to determine the error caused by the mismatch between the measurement port and the unknown impedance.

## Ratio-to-dB Calculator

The Ratio-to-dB Calculator simply converts between voltage ratio, power ratio, and dB.

## Antenna Calculator

The Antenna Calculator calculates the various antenna measurements using physical and electrical parameters.

• Free Space Path Loss
It uses the standard Free Space Path Loss as function of a single frequency point. This formula works for direct line of site transmission only.
• Friss Equation
The Friss Equation for Free Space Loss includes the Gains and Path Loss in terms of transmitted power. This formula calculates the Rx power of the network and works for direct line of size transmission only.
• Far Field calculator
The Far Field Calculator returns the approximate Reactive, Near and Far Field regions (in terms of distance) from the aperture of a transmitting antenna. In order to measure the far field radiation pattern of an antenna and have a flat phase - front at the Receive antenna aperture, the distance from the Transmit to Receive antenna must be equal to or greater than the value calculated.

## Noise Calculator

The Noise Calculator consists of various calculators related to measurements of noise power, noise figure, and noise parameters:

• F,NF,Te Calculator
The F, NF, Te Calculator converts between noise factor, noise figure, and effective-input-noise temperature.
• kTB Calculator
The kTB Calculator calculates noise- power-based on temperature and bandwidth.
• ENR Calculator
The ENR Calculator converts between Tcold, Thot and ENR (excess noise ratio).
• Y-factor Calculator
The Y-factor Calculator calculates the Y-factor-based noise figure from Pcold, Phot, and ENR.