Complementary error function and Q-function
Analyze the bit error rate (BER) over an AWGN channel for QPSK and QAM. A calculator and a table help you finding out the values of Q(x) and erfc(x) depending on x.
QAM bit error probability calculator
Calculate the M-ary QAM bit error probability in AWGN depending on energy per bit and the constellation size M.
This little tool helps you calculating logarithmic decibels into a linear power value and vice versa.
Fast Fourier transform (FFT) illustrated
Calculate the FFT of signals. The FFT takes a time-discrete signal and computes the spectrum. Examples of time and frequency signals are shown, DC component, Dirac pulse, cosine, pulse, complex rotating phasor.
Inverse Fast Fourier transform (IFFT)
Calculate the Inverse Fourier Transform (IFFT). Enter a frequency-based signal and transform it to a time-based Signal.
Power invariant fast Fourier transform (FFT)
The power of the FFT output signal differs from the input signal power due to an asymmetry in the FFT / IFFT definitions. This FFT variant keeps input and output signal powers equal.
- Power invariant inverse fast Fourier transform (IFFT)