Sign in Subscribe

IBERT (integrated bit error ratio tester)

Last updated on 
5G & 6G Prime Membership Telecom

Integrated Bit Error Ratio Tester (IBERT) is a type of testing methodology used to assess the performance of high-speed digital communication systems. It is an effective method for determining the integrity and functionality of complex communication systems, including those used in data centers, telecom networks, and other mission-critical applications.

In this article, we will explain IBERT in detail, including its features, benefits, and limitations.

Overview of IBERT

IBERT is a testing technique that involves generating and transmitting a digital signal through a high-speed communication link and then measuring the quality of the received signal. The technique can be used to test a wide range of communication systems, including PCIe, SATA, SAS, and Ethernet interfaces.

The IBERT module is typically implemented as a hardware IP core in a Field-Programmable Gate Array (FPGA). The module is designed to be inserted into the data path of the communication system, allowing it to monitor the transmitted and received data streams.

The IBERT module is capable of generating a wide range of test patterns, including pseudo-random binary sequences (PRBS), which are commonly used in high-speed communication testing. The module also includes a receiver circuit that performs error detection and correction.

The IBERT module can be configured to operate at different data rates, allowing it to test systems operating at speeds of up to 56 Gbps or higher. The module can also be configured to support different voltage levels and signal formats.

How IBERT Works

The IBERT module works by generating a test pattern and transmitting it through the communication system under test. The transmitted signal is then received and analyzed to determine the bit error rate (BER), which is a measure of the number of bit errors that occur during transmission.

The IBERT module generates a test pattern using a built-in test pattern generator (BTPG). The BTPG is typically implemented as a digital circuit that generates a specific sequence of bits according to a predefined algorithm. The algorithm used to generate the test pattern determines the complexity of the sequence and its ability to detect specific types of errors.

Once the test pattern is generated, it is transmitted through the communication system under test. The transmitted signal is received by the IBERT module, which performs error detection and correction using a built-in error detector (BED) and error corrector (BEC). The BED and BEC circuits are typically implemented using digital signal processing techniques.

The received signal is compared to the original test pattern to determine the bit error rate (BER). The BER is calculated as the number of bit errors that occur during transmission divided by the total number of bits transmitted. The IBERT module can be configured to perform BER measurements over a specified interval of time or a specified number of bits.

Features of IBERT

The IBERT module has several features that make it an effective testing tool for high-speed communication systems:

  1. Support for High-Speed Communication: The IBERT module is capable of testing communication systems operating at data rates of up to 56 Gbps or higher. This makes it suitable for testing high-speed interfaces such as PCIe, SATA, SAS, and Ethernet.
  2. Wide Range of Test Patterns: The IBERT module can generate a wide range of test patterns, including PRBS and other specialized patterns. This allows it to test for specific types of errors and to identify the root cause of any issues that are detected.
  3. Built-in Error Detection and Correction: The IBERT module includes built-in error detection and correction circuits that can detect and correct errors in the received data stream. This helps to ensure that the measured BER is accurate and reliable.
  4. Configurability: The IBERT module is highly configurable, allowing it to be adapted to different communication systems and environments. It can be configured to support different voltage levels, signal formats, and data rates.
  5. Ease of Use: The IBERT module is designed to be easy to use, with a simple and intuitive interface. This makes it accessible to a wide range of users, including engineers and technicians who may not have extensive experience with high-speed communication testing.

Benefits of IBERT

The use of IBERT for testing high-speed communication systems offers several benefits, including:

  1. Early Detection of Issues: By using IBERT to test communication systems during development and deployment, issues can be detected early in the process, before they become more serious and expensive to fix.
  2. Improved Reliability: IBERT can help to improve the reliability of communication systems by identifying potential issues and allowing them to be addressed before they impact system performance.
  3. Faster Time to Market: By using IBERT to test communication systems, engineers and technicians can identify and resolve issues more quickly, which can help to reduce development time and speed up time to market.
  4. Increased Confidence: By using IBERT to test communication systems, engineers and technicians can have greater confidence in the performance and reliability of the systems they are deploying.

Limitations of IBERT

While IBERT offers many benefits, there are some limitations to its use. These include:

  1. Limited Scope: IBERT is designed to test the integrity of the data transmission path, but it does not provide information about other aspects of system performance, such as power consumption or latency.
  2. Incomplete Testing: While IBERT can detect bit errors, it does not provide a complete picture of system performance. Additional testing may be required to validate the overall functionality of the communication system.
  3. Cost: Implementing IBERT can require significant hardware and software resources, which can add to the cost of development and deployment.

Conclusion

IBERT is a powerful testing tool for assessing the performance and integrity of high-speed communication systems. Its ability to generate a wide range of test patterns, perform error detection and correction, and support different voltage levels and signal formats makes it an effective tool for testing a wide range of communication systems.

While there are some limitations to the use of IBERT, its benefits, including early issue detection, improved reliability, faster time to market, and increased confidence, make it an essential tool for engineers and technicians working with high-speed communication systems.