optic.comm.metrics.bert

bert(Irx, bitsTx=None, seed=123)

Calculate Bit Error Rate (BER) and Q-factor for optical communication using On-Off Keying (OOK).

Parameters:

  • Irx (numpy.np.array) – Received signal intensity values.

  • bitsTx (numpy.np.array, optional) – Transmitted bit sequence. If not provided, a random bit sequence is generated.

  • seed (int, optional) – Random seed for bit sequence generation when bitsTx is not provided.

Returns:

  • BER (float) – Bit Error Rate, a measure of the number of erroneous bits relative to the total bits.

  • Q (float) – Q-factor, a measure of signal quality in the communication system.

Notes

This function calculates the BER and Q-factor for an optical communication system using On-Off Keying (OOK) modulation. The received signal intensity Irx and an optional transmitted bit sequence bitsTx are required. If bitsTx is not provided, a random bit sequence is generated using the specified seed.

The following statistics are calculated for the received signal: - I1: The average value of the signal when the transmitted bit is 1. - I0: The average value of the signal when the transmitted bit is 0. - std1: The standard deviation of the signal when the transmitted bit is 1. - std0: The standard deviation of the signal when the transmitted bit is 0.

The optimal decision threshold Id and the Q-factor are calculated based on the signal statistics.

The function then applies the optimal decision rule to estimate the received bit sequence bitsRx. The Bit Error Rate (BER) is calculated by comparing bitsRx to bitsTx.

References

[1] Agrawal, Govind P. Fiber-optic communication systems. John Wiley & Sons, 2012.