CISPR

CISPR
Name	International Special Committee on Radio Interference
Founded	1934
Parent	International Electrotechnical Commission

CISPR. The International Special Committee on Radio Interference is a pivotal body within the International Electrotechnical Commission dedicated to establishing international standards for controlling electromagnetic interference. Since its formation, it has developed a comprehensive suite of measurement procedures and emission limits that are adopted worldwide to ensure the electromagnetic compatibility of electrical and electronic devices. Its work is fundamental to the global regulatory framework, facilitating international trade and protecting the radio frequency spectrum from disruptive interference.

Overview and history

The committee was established in 1934, prompted by growing concerns over disruptive interference from emerging electrical technologies to vital radio communication services. Early work focused on interference from sources like ignition systems in automobiles and industrial equipment. Over the decades, its mandate expanded dramatically with the proliferation of information technology equipment, switch-mode power supply units, and lighting equipment such as fluorescent lamps. Key historical milestones include the development of the first standardized measurement methods for radio-frequency interference and the establishment of emission limits that were later incorporated into the regulatory frameworks of bodies like the Federal Communications Commission in the United States.

Standards and publications

CISPR publishes a widely recognized series of standards, each designated with a "CISPR" prefix followed by a number. Foundational documents include CISPR 16, which specifies the apparatus and methods for measuring disturbance characteristics, and CISPR 11, which sets limits for industrial, scientific, and medical equipment. Other critical standards cover multimedia equipment (CISPR 32), vehicles, boats, and internal combustion engines (CISPR 12 and CISPR 25), and household appliances (CISPR 14-1). These publications are continuously revised by technical committees to address new technologies, such as wireless power transfer systems and LED lighting.

Measurement methods and equipment

The committee defines precise methodologies for quantifying electromagnetic emissions, conducted using specialized apparatus calibrated to international norms. Core measurement techniques involve the use of an open-area test site or a semi-anechoic chamber, along with instruments like the spectrum analyzer and the EMI receiver. Key apparatus specified in its standards includes various antenna types, such as the biconical antenna and the log-periodic antenna, and standardized artificial networks like the line impedance stabilization network. These methods ensure reproducible results for both conducted emissions and radiated emissions across a frequency range from 9 kHz to 18 GHz.

Subcommittees and scope

Technical work is divided among several active subcommittees, each with a defined scope. CISPR/A deals with radio interference measurements and statistical methods. CISPR/B focuses on interference from industrial, scientific, and medical apparatus, as well as related equipment like microwave ovens. CISPR/D sets standards for vehicles and internal combustion engines, while CISPR/F addresses household appliances and similar apparatus. CISPR/H is responsible for protecting specific services like broadcasting and telecommunication, and CISPR/I handles information technology equipment, multimedia devices, and receivers.

Relationship to other standards bodies

The committee operates under the umbrella of the International Electrotechnical Commission and works in close liaison with other major international organizations. It maintains a critical partnership with the International Organization for Standardization, particularly in areas concerning electromagnetic compatibility. Its standards form the basis for regional regulations in the European Union, implemented through directives like the Electromagnetic Compatibility Directive. It also collaborates with bodies such as the International Telecommunication Union and national committees including the American National Standards Institute and Deutsches Institut für Normung to ensure global harmonization.

Applications and impact

CISPR standards are applied globally to ensure that products do not cause harmful interference and can operate reliably in their intended electromagnetic environment. This is crucial for the European Conformity marking process and for market access in regions like North America and Asia. The standards impact a vast array of industries, from automotive engineering and aerospace to consumer electronics and renewable energy systems involving wind turbines. By providing a unified technical foundation, its work reduces trade barriers, supports innovation, and protects essential services like air traffic control and emergency service communications from disruption.

Category:International Electrotechnical Commission Category:Technical standard organizations Category:Electromagnetic compatibility