Constellation Diagrams of ASK, PSK, and FSK (with MATLAB Code + Simulator)

Constellation Diagrams: ASK, FSK, and PSK

Comprehensive guide to signal space representation, including interactive simulators and MATLAB implementations.

📘Overview 🧮Simulator ⚖️Theory Q-function 📚Resources

BASK (Binary ASK) Modulation

Transmits one of two signals: 0 or $\sqrt{E_b}$, representing binary 0 and 1.

BFSK (Binary FSK) Modulation

Transmits one of two signals: $\sqrt{E_b}$ on the Y-axis or $\sqrt{E_b}$ on the X-axis. These are orthogonal signals.

BPSK (Binary PSK) Modulation

Transmits $+\sqrt{E_b}$ or $-\sqrt{E_b}$ (antipodal signaling).

Signal Space Simulator

Visualize Constellation Diagrams with Noise Control.

SNR (dB): 15

Add AWGN Noise

Modulation Type BPSK BFSK BASK

Theory & Key Points

• ✔BASK: Bit '0' is low voltage; bit '1' is high. Distance $\sqrt{E_b}$.
• ✔BFSK: Bit '0' and '1' are orthogonal. Distance $\sqrt{2E_b}$.
• ✔BPSK: Antipodal signaling. Distance $2\sqrt{E_b}$. Read more [↗]

Figure 1: Constellation diagrams showing x-axis (Real) and y-axis (Imaginary).

ASK vs FSK vs PSK: Comparison Table

Parameter	BASK	BFSK	BPSK
Noise Immunity	Very Low	High	Highest
BER Formula	$Q(\sqrt{E_b/2N_0})$	$Q(\sqrt{E_b/N_0})$	$Q(\sqrt{2E_b/N_0})$

Boundary Simulator (Q-Function)

SNR (dB): 10

Modulation BPSK (Antipodal) BFSK (Orthogonal) BASK (OOK)

Enable Noise

Tail Probability Viz

Threshold Distance ($x$)

Distance ($x$):1.5

Prob $Q(x)$:0.0668

📖 Detailed Theory

• Constellation Diagram of ASK
• Constellation Diagram of FSK
• Constellation Diagram of PSK

🕹️ More Simulators

• Advanced M-ary Modulation Simulator: Constellation, min dist, Efficiency, SER, EVM (RMS)

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