Digital Modulation BER Calculator

Calculate bit error rate for common digital modulation schemes as a function of Eb/N0.

What is this?

When you hear static during a phone call or see pixelation on TV, that's bit errors. BER (Bit Error Rate) measures how many bits get garbled during transmission — like counting how many letters in a text message arrive corrupted.

Why does this matter? Streaming 4K video requires an incredibly low error rate — even 1 wrong bit in a million can cause a visible glitch. Engineers use this calculator to choose the right modulation scheme and signal power for the quality they need. Higher-order schemes (256QAM) pack more data into the same channel, but need a much cleaner signal to work reliably.

Modulation Scheme
Select how data is encoded onto the radio signal.
Simplest — 1 bit per symbol, most robust

Energy per bit vs noise — higher = cleaner signal

dB
0 dB (noisy)15 dB30 dB (clean)

BER Results — BPSK
1 bits encoded per symbol
Bit Error Rate3.88×10⁻⁶at Eb/N0 = 10 dBPoor — frequent errors, service degraded

EVM (signal cleanliness)

31.62%

Bits per Symbol

1

Minimum Eb/N0 needed for BER = 10⁻⁶

10.53 dB

BER vs Signal Quality Sweep

Eb/N0 (dB)Error Rate
0 dB7.86×10⁻²
2 dB3.75×10⁻²
4 dB1.25×10⁻²
6 dB2.39×10⁻³
8 dB1.91×10⁻⁴
10 dB3.88×10⁻⁶
12 dB9.03×10⁻⁹
14 dB6.86×10⁻¹³
16 dB2.27×10⁻¹⁹
18 dB1.40×10⁻²⁹
20 dB1.04×10⁻⁴⁵

Real-world example

Streaming 4K video requires a BER below 10⁻⁶ — even 1 wrong bit in a million causes a visible glitch. Cable TV systems using 256QAM need Eb/N0 above ~27 dB to deliver this. Your current settings show 3.88×10⁻⁶ errors, which is too high for reliable video.

BER assumes AWGN channel with Gray coding and ideal coherent detection. Real systems require additional margin for hardware impairments, phase noise, and multipath fading.