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Online Simulator for M-ary QAM Signal Generation


M-ary Quadrature Amplitude Modulation (M-QAM)

Modulating both Amplitude and Phase for high-speed data transmission.

Parameters

20 Hz
1.0
1.0s

How M-QAM Simulation Works

1 Bit Grouping

The input bits are divided into groups of k = log₂(M). For 16-QAM, bits are taken in groups of 4. Each group is converted to a decimal symbol (0 to M-1).

2 Constellation Mapping

A square grid is generated. For 16-QAM, we use a 4x4 grid. Symbols are mapped to I (In-phase) and Q (Quadrature) coordinates. We then normalize the power so the average energy matches your Amplitude setting.

3 Signal Equation

The final waveform is generated using two orthogonal carriers:

s(t) = I·cos(2Ï€fct) - Q·sin(2Ï€fct)

Observe the Waveform: Larger I/Q values result in higher amplitudes, while the combination of I and Q shifts the phase.

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