# What is a bit error rate tester?

## What is a bit error rate tester?

A bit error rate tester (BERT), also known as a “bit error ratio tester” or bit error rate test solution (BERTs) is electronic test equipment used to test the quality of signal transmission of single components or complete systems. Digital communication analyser is optional to display the transmitted or received signal.

## How do you calculate bit error?

The BER is calculated by comparing the transmitted sequence of bits to the received bits and counting the number of errors. The ratio of how many bits received in error over the number of total bits received is the BER. This measured ratio is affected by many factors including: signal to noise, distortion, and jitter.

**What causes bit error rate?**

For fibre optic systems, bit errors mainly result from imperfections in the components used to make the link. These include the optical driver, receiver, connectors and the fibre itself. Bit errors may also be introduced as a result of optical dispersion and attenuation that may be present.

### Which is the best bit error ratio tester?

Our NRZ and PAM4 coding schemes for 400G solution deliver a fully integrated 64Gbaud BER test. Keysight offers the broadest choice of bit error rate testers – covering affordable manufacturing test and high-performance characterization with compliance testing up to 32 Gb/s.

### How long does it take to test a bit error rate?

For Gigabit Ethernet that specifies an error rate of less than 1 in 10^12, the time taken to transmit the 10^12 bits of data is 13.33 minutes. To gain a reasonable level of confidence of the bit error rate it would be wise to send around 100 times this amount of data.

**What is the error rate of a BER test?**

If one error were detected while sending 10 12 bits, then a first approximation may be that the error rate is 1 in 10 12, but this is not the case in view of the random nature of any errors that may occur. In theory an infinite number of bits should be sent to prove the actual error rate, but this is obviously not feasible.

## Why are pseudorandom codes used in bit error rate testing?

Accordingly to assist making measurements faster, mathematical techniques are applied and the data that is transmitted in the test is made as random as possible – a pseudorandom code is used that is generated within the bit error rate tester. This helps reduce the time required while still enabling reasonably accurate measurements to be made.