An Overview of EMI Measurement Equipment for Conducted and Radiated Emission Analysis

In recent years, with the popularity of electronic devices and the rapid development of wireless communication, the potential harm of electromagnetic field radiation to human health has attracted wide attention. In order to protect people’s health and ensure the normal operation of electronic devices, it has become particularly important to conduct EMI, conducted emission and radiated emission tests on electronic devices.

The EMI measurement equipment is a specialized instrument used to test the radiation levels of electronic devices. It can be used for testing signal and control conduction interference, helping businesses and research institutions evaluate and improve the electromagnetic performance of their products. Below, we will introduce the working principle of the EMI measurement equipment and its testing solution.

EMI electromagnetic interference testing reflects the strength of interference from surrounding electronic devices by measuring the size of the electromagnetic wave signals generated and emitted by the tested device under normal working conditions. Electromagnetic interference tests mainly include conduction emissions, radiation emissions, power interference, magnetic induction current, click noise interference, current harmonics, voltage fluctuations, and flicker. Electromagnetic interference consists of three elements: the interference source, the coupling channel, and the EMI receiver, commonly referred to as the three elements of interference.

The working principle of the EMI measurement equipment mainly includes two steps: transmission and reception. First, the instrument generates electromagnetic signals within a certain frequency range and radiates the signals to the tested device through a transmitting antenna. Then, the receiving antenna collects the radiation signals emitted by the tested device and converts them into electrical signals for analysis and processing within the testing instrument.

EMI conducted emission and radiated emission testing:
Radiated emission measurements are initially conducted in an anechoic chamber to generate a range of frequencies. The test equipment is then moved to an open area within the test site. Only by conducting radiated emission testing at the EUT azimuth and antenna height can the maximum level of radiation emission be detected. This requires the use of a turntable and antenna positioner to adjust the antenna height and change its orientation from horizontal to vertical. Conducted emission measurements must be conducted within the frequency range of 150 kHz to 30 MHz to determine the voltage of radio frequency noise conducted to ground from the power input terminals of the device, which are directly connected to a common power grid (either through a separate transformer or power supply). Typically, the equipment is tested using regular power cords or cables that resemble power cords and have various shielding features.

Radiated emission testing is conducted in a shielded and sufficiently large anechoic chamber to accommodate the entire test system and fully control the intensity of the electromagnetic field. The environmental conditions of the test system must maintain the same electromagnetic field intensity. The frequency steps and power requirements are specified in the relevant standards. The output of the test system needs to be controlled to prevent interference from entering. Conducted emission testing can be performed by transmitting the RF signal onto an external power supply and signal cable with fixtures. In this case, the power supply and signal cable act as the passive receiver of the signals transmitted by the antenna network.

During EMI conducted emission and radiated emission testing, there are several key testing solutions that need to be followed. First is the selection of the testing environment. To ensure the accuracy of the testing results, the testing environment should be an electromagnetic shielding room that effectively shields external interference. Second is the selection of the testing frequency. Different electronic devices generate different radiation interference within different frequency ranges, so the appropriate testing frequency range should be selected based on the characteristics of the tested device. Generally, the testing frequency range should include the operating frequency and its surrounding multiples and harmonics.

Next is the setting of the testing parameters. During EMI conducted emission and radiated emission testing, certain testing parameters need to be set to evaluate the level of radiation from the device. Common testing parameters include radiation power, radiation field strength, radiation bandwidth, etc. These parameters will help determine whether the device complies with relevant international standards and regulations.

In addition to the above testing steps and parameter settings, there are also testing methods and techniques that can improve the testing effectiveness. For example, a combination of peak and average methods can be used to evaluate the radiation level of the device. Additionally, different radiation interference levels under different conditions can be tested by changing the device’s operating status and setting different operating modes. Furthermore, external filters and shielding measures can be used to reduce the impact of external interference on the testing results.

EMI measurement equipment not only helps businesses and research institutions evaluate and improve the electromagnetic performance of their products, but also provides relevant testing reports and data analysis as references for business decisions and product design. By conducting EMI conduction emission and radiation emission testing, the normal operation of electronic devices can be ensured, and the potential impact on the surrounding environment and human health can be minimized.

With the continuous progress of technology and the increasing popularity of electronic devices, the importance of EMI conduction and radiation testing is becoming more prominent. By using the EMI conduction and radiation tester, we can accurately evaluate the radiation levels of electronic devices and make improvements and optimizations to products. This helps improve the competitiveness and market recognition of the products, while also ensuring the health and safety of users.

In conclusion, the EMI measurement equipment is a very important tool for evaluating the radiation performance of electronic devices. By following appropriate testing solutions and setting relevant testing parameters, we can accurately evaluate the radiation levels of products and take corresponding measures for improvement. This will help ensure the health and safety of users, enhance the competitiveness and market recognition of products. At the same time, we need to continue researching and improving the EMI conduction and radiation tester to meet the increasingly complex and diverse market demands for electronic devices.

Finally, I hope that in the future development, the EMI measurement equipment can become more intelligent and convenient to meet the ever-changing market demands. Through continuous innovation and improvement, we can better protect people’s health and ensure the normal operation of electronic devices, and together build a safe and reliable environment for electronic devices.

EMI receiver system for EMI (Electromagnetic Interference) radiation conduction or conducted emissions testing. The EMI-9KB EMI receiver is made of full closure structure and strong electro-conductibility material, which has high shielding effect. Due to the new technology for the EMI Test System, it solved the instrument self-EMI problem. The test results are according to the international format test report. The EMI Test System EMI-9KB fully meets CISPR15:2018, CISPR16-1, GB17743, FCC, EN55015 and EN55022.

EMI-9KB EMI Test Receiver

Lisun Instruments Limited was found by LISUN GROUP in 2003. LISUN quality system has been strictly certified by ISO9001:2015. As a CIE Membership, LISUN products are designed based on CIE, IEC and other international or national standards. All products passed CE certificate and authenticated by the third party lab.

Our main products are Goniophotometer, Integrating Sphere, Spectroradiometer, Surge Generator, ESD Simulator Guns, EMI Receiver, EMC Test Equipment, Electrical Safety Tester, Environmental Chamber, Temperature Chamber, Climate Chamber, Thermal Chamber, Salt Spray Test, Dust Test Chamber, Waterproof Test, RoHS Test (EDXRF), Glow Wire Test and Needle Flame Test.

Please feel free to contact us if you need any support.
Tech Dep: Service@Lisungroup.com, Cell/WhatsApp:+8615317907381
Sales Dep: Sales@Lisungroup.com, Cell/WhatsApp:+8618117273997