Performance and Application Analysis of LISUN EMI Receiver Test System

Abstract
With the widespread application of electronic equipment, electromagnetic compatibility (EMC) has become a key indicator in product design and production. This paper takes the LISUN EMI-9KB EMI Receiver Test System as the research object, and analyzes in detail its technical characteristics, testing capabilities and application scenarios. The system adopts a fully enclosed structure and highly conductive materials, achieving excellent shielding effect and fundamentally solving the problem of the equipment’s own interference. Through test procedures and report formats that comply with international standards, the EMI-9KB can meet the requirements of multiple specifications such as CISPR, GB, and FCC, providing reliable support for EMC certification of electronic equipment. Actual test data shows that the measurement accuracy of the system in the 30MHz-1GHz frequency band can reach ±1.5dB, and the repeated test deviation is less than 0.8dB, demonstrating excellent stability and accuracy.

1. Introduction
Against the backdrop of the rapid development of information technology, the problem of electromagnetic interference between electronic devices has become increasingly prominent. Electromagnetic Interference (EMI) not only affects the normal operation of equipment, but also may pose potential threats to human health and public safety. To regulate the electromagnetic radiation characteristics of electronic equipment, a series of international and domestic standards such as CISPR, GB, and FCC have been successively introduced, requiring electronic equipment to pass strict EMI test certification before being launched on the market.

Traditional EMI test systems have problems such as high self-interference of equipment, insufficient test accuracy, and complex operation, which are difficult to meet the testing needs of the modern electronic industry. The EMI-9KB fully automatic EMI test system launched by LISUN Group adopts innovative design and technology, effectively solving the technical pain points of traditional equipment. This paper will conduct a comprehensive analysis of the EMI-9KB test system from aspects of system structure, technical parameters, standard compliance and practical application.

2. Technical Characteristics of the EMI-9KB Test System
2.1 Hardware Structure Design
The EMI-9KB test system adopts a fully enclosed structural design. The main body of the device is made of high-conductivity alloy materials, and a 360-degree all-round electromagnetic shielding environment is constructed through multi-point grounding technology. This design enables the system’s shielding effectiveness to reach more than 80dB (in the 30MHz-1GHz frequency band), which can effectively block the interference of external electromagnetic signals.

The core components of the system include:
• EMI-9KC Test System includes: EMI-9KC EMI Receiver built-in Attenuator (9K-1GHz), LISN Artificial Network Power, CDNE-M316 Coupling/Decoupling Network for Emission, Isolation Transformers and cables.
• EMI-9KB Test System includes: EMI-9KB EMI Receiver (9K-300MHz), LISN Artificial Network Power, CDNE-M316 Coupling/Decoupling Network for Emission, Isolation Transformers, Attenuator and cables.
• EMI-9KA Test System includes: EMI-9KA EMI Receiver (9K-30MHz), LISN Artificial Network Power, Isolation Transformers, Attenuator and cables.

3. System Performance Parameters and Testing Capabilities
3.1 Main Technical Parameters
The core performance parameters of the EMI-9KB are shown in Table 1:

Parameter Item	Technical Index	Test Condition
Frequency Range	9kHz-1GHz	Full frequency band coverage
Measurement Accuracy	±1.5dB	30MHz-1GHz
Display Unit	dBμV, dBμA, dBm, μV/m	Freely switchable
Scanning Speed	0.1-100MHz/s	Adjustable step
Dynamic Range	>100dB	Full frequency band
Resolution Bandwidth	10Hz-1MHz	In line with CISPR16-1-1
Preamplifier Gain	0-30dB	1dB step
Test Repeatability	<0.8dB	10 consecutive tests on the same equipment

3.2 Coverage of Test Functions
The EMI-9KB system can complete two main types of tests:
• Conducted interference test: Measure the interference signals generated by the equipment on the power line through LISN, with a frequency range of 9kHz-30MHz
• Radiated interference test: Measure the electromagnetic signals emitted by the equipment into the space through the test antenna, with a frequency range of 30MHz-18GHz

The system supports four detection methods: peak, quasi-peak, average and effective value, which can meet the special requirements of different standards for measurement methods.

4. Analysis of Practical Application Cases
4.1 EMC Certification Test for Lighting Equipment
A lighting enterprise needed to pass the EN55015 standard certification during the R&D of LED lamps. When using the EMI-9KB system for testing, the following problems were found:

• There was a phenomenon of excessive radiated interference in the 30-80MHz frequency band
• A significant peak of conducted interference appeared at 150kHz

Based on the test data, the technicians added a common-mode inductor to the lamp power module and optimized the PCB layout. After rectification, the test was conducted again, and all indicators met the standard requirements, and the test report was directly accepted by the EU certification authority.

4.2 Radiated Interference Test for Information Technology Equipment
When testing a certain type of laptop computer in accordance with FCC Part 15, the EMI-9KB system accurately captured the radiated excessive signal in the 520MHz frequency band. Through the spectrum analysis function of the system, the interference source was located to the clock signal of the wireless network card. After adjusting the clock frequency and adding shielding measures, the interference signal was reduced by 28dB, fully meeting the standard limits.

5. System Advantages and Industrial Value
5.1 Core Competitive Advantages
Compared with similar products, the EMI-9KB has the following significant advantages:
• Fully automated test process, from equipment connection to report generation, no manual intervention is required throughout the process, and the test efficiency is improved by 40%
• Excellent shielding performance, which can obtain standard-compliant test results in an ordinary laboratory environment, reducing the dependence on anechoic chambers
• High-precision measurement capability, ensuring that products pass the certification test at one time, reducing the test cost and time for enterprises
• Open data interface, supporting integration with Product Lifecycle Management (PLM) systems to build a complete quality control system

5.2 Industrial Application Value
The promotion and application of the EMI-9KB test system has multiple values for the development of the electronic industry:
• Helping enterprises identify EMI problems in product design in advance and shortening the R&D cycle
• Reducing the risk of product certification failure and improving the success rate of market access
• Enhancing the electromagnetic compatibility of electronic equipment and reducing mutual interference between equipment
• Promoting the overall technological level of the industry and facilitating the R&D of green and environmentally friendly electronic products

6. Conclusions and Prospects
The LISUN EMI-9KB EMI Receiver Test System realizes high-precision and high-efficiency EMI test functions through innovative structural design and advanced anti-interference technology. Its comprehensive standard compliance and excellent performance make it an ideal choice for EMC certification testing of electronic equipment.

With the development of emerging technologies such as 5G and the Internet of Things, the electromagnetic environment of electronic equipment will become more complex, putting forward higher requirements for EMI testing technology. In the future, the EMI-9KB system can be further upgraded in the following aspects:

• Expand the testing capability of the millimeter-wave frequency band (above 24GHz)
• Develop AI-assisted interference source localization function
• Build a cloud-based test data management platform to realize multi-site collaborative testing

Tags：EMI-9KB