Relation between snr and ber

This is typically a number between 0.1 (every 10th bit is bad!) and 0.000001 (Only one in a million is bad). This ratio is closely linked to the Signal-to-Noise-Ratio (SNR) which is measured in decibels (dB).
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Bit Error Rate (BER)

1. What is the relation between SNR and signal output quality?
2. Why BER and SNR are so important in a communication system?
3. What is the formula for BER?
4. How is the BER of BPSK related to the SNR in an AWGN system?

What is the relation between SNR and signal output quality?

A signal-to-noise ratio over 0 dB indicates that the signal level is greater than the noise level. The higher the ratio, the better the signal quality.

Why BER and SNR are so important in a communication system?

For a fixed transmission rate R, a BER vs SNR curve will show you how well the receiver works with changing SNR levels and is arguably one of the best ways too assess overall receiver performance.

What is the formula for BER?

Bit Error Rate Formula

To calculate bit error rate, divide the number of bits in error by the total bits received.

How is the BER of BPSK related to the SNR in an AWGN system?

For realizing that, the effect of noise is represented in the baseband with Gaussian random samples added to each signal sample. The signal to noise ratio (SNR) is varied to show the effect of SNR on BER. Finally the theoretical BER, i.e. Q(sqrt(2*SNR)) is also plotted to show the correctness of simulation.