Testing : EMC

Electro-Magnetic Compatibility

At the heart of MIRA's EMC engineering service is our extensive suite of ISO 17025 accredited EMC test laboratories. With nine chambers of different sizes and specification we are able to cater for all types of vehicle, component and system test. Our laboratories operate 24 hours a day and are maintained to the highest standards. Regular updates ensure the latest customer and legislative requirements are always met.

EMC Emissions Testing

Vehicles, electrical equipment and machines generate RF (radio frequency) emissions. It is essential these emissions do not interfere with the environment or their own sensitive electrical and electronic systems. At MIRA we have the facilities to evaluate the levels and frequencies of these RF emissions. We then use our expertise to ensure they fall below the limits set by legislation and our customers own specifications.

Emissions testing in MIRA's Open Area Test Site

Vehicle entertainment systems are particularly vulnerable to RF emissions; details of MIRA's audio interference test method can be found here:

Audio interference testing

A brochure with details of MIRA's EMC emissions and audio evaluation can be downloaded here:

EMC emissions and audio evaluation pdf (492Kb)

EMC Immunity Testing

We live in an RF rich environment. In addition to vehicles and electrical machinery powerful sources of high electromagnetic fields include mobile phone antennas, power lines, radar and radio transmitters. Ensuring the increasingly complex systems integrated in to vehicles and other products are not affected by these fields requires state-of-the-art facilities and test methods. At MIRA our specialist EMC engineers lead the industry in developing and applying non-intrusive test methods helping our customers produce safe and reliable products.

MIRA's in-house developed software enables us to control our immunity test system, giving us the flexibility to perform stepped or frequency-swept tests that can be synchronised with modulation characteristics of the frequency spectrum; CW, pulse, keyed, radar, AM, Tetra, Bluetooth,GSM and many more. This test system software can also control pneumatic actuators to cycle the system under test in its normal operating mode. Our test system can then be linked into your monitoring system to identify test levels and frequencies for post test analysis.


Systems such as adaptive cruise control require innovative EMC test methods

New Methods for New Systems

The rapid increase in number and complexity of electrical and electronic systems across vehicles of all types has required us to develop new test methods. These include methods for evaluating the performance of the following systems during radiated RF emissions:

Anti-lock Braking Systems (ABS)
Electronic Stability Program (ESP) / Traction control
Adaptive Cruise Control / Automatic Distance Regulation
Automatic rain sensors
Headlamp leveling
Automatic headlamp controls
Parking aids
RKE (Remote Keyless Entry)
Tiptronic gearshift mechanisms
Navigation systems
Automatic speed control systems
Night vision systems
Electric park brake and automatic roll braking systems

The above list, though far from exhaustive, serves to illustrate the types of systems that are becoming commonplace across vehicles in all sectors. Many are active safety systems so their reliability is critical.

Further details can be downloaded here:

Vehicle Immunity Test Capabilities pdf (509Kb)

Airbag Assessment

MIRA has considerable experience in the measurement of RF immunity robustness of vehicle restraint systems, at both vehicle and component level. As well as using conventional techniques MIRA has developed a test method to directly monitor the bridge wire temperature. At vehicle level this method gives a high level of confidence that airbag pyrotechnics will not deploy in RF fields. At component level the suppression performance of filters can accurately be assessed.

An unwanted airbag deployment could have devastating consequences

(Flash movie object - right click to play)

Further details of MIRA's airbag RF robustness testing is included in this brochure:

EMC Airbag RF Robustness Testing pdf (377KB)

Pre-compliance Testing

Component and system testing

The increasingly tight time constraints of today's vehicle programmes means there is too much risk involved in leaving EMC testing to be done at the vehicle level. Indeed vehicle manufacturers insist that the systems they are fitting have passed stringent test schedules prior to integration in to the vehicle. In most cases the responsibility for passing these tests is delegated to the tier one system supplier. As an approved EMC test service provider to the world's major vehicle manufacturers MIRA is an ideal development partner for any component or system supplier involved in one of these programmes.

We have experience of working to test specifications for Ford, Jaguar, Land Rover, Aston Martin, Volvo, General Motors, DaimlerChrysler, Toyota, Honda, Nissan, Renault, PSA, VW, Audi, Bentley, BMW and more.

EMC Component Testing

Systems Integration and Vehicle Pre-production Testing

Programme delays are extremely costly. MIRA works with tier 1 suppliers and vehicle manufacturers to find ways of gaining confidence that a system will work reliably without causing interference to other systems. Pre-production testing is a cost-effective way of identifying potential issues whilst there is time in the programme to solve them. MIRA's wealth of experience in integrating all types of vehicle systems includes building prototypes enabling design modifications to be introduced rapidly saving time and money.

Prototype Vehicle EMC test in MIRA's Semi-anechoic chamber

Development testing

Problem resolution

We strive to eliminate EMC issues by employing EMC design best practice and working with tier one suppliers to produce compliant systems and components. However the complex interactions between systems and the constraints of the vehicle package can still throw up EMC concerns. This is where MIRA's many years of EMC development experience pays dividends. Using our suite of vehicle EMC facilities we can evaluate the vehicle's EMC performance against manufacturer's specifications and relevant legislative requirements.

Because we employ EMC specialists who spend the majority of their working days tackling EMC concerns there are few problems they haven't seen before or found solutions to. Many of our customers have been surprised not just with the speed with which we've solved their potential programme stopper but also with the simplicity of the solution.

Type approval

As a Competent Body for EMC, MIRA acts on behalf of manufacturers, their supply chain, importers and agents seeking vehicle and component road vehicle type approvals by managing the homologation process and obtaining certificates from Type Approval Authorities

MIRA is also a Notified Body for other directives appointed by the DTi and notified to Europe, MIRA evaluates equipment (such as mobile machinery) installed on vehicles and issues certificates valid throughout the EU. MIRA manages the radio licence exemption process and obtains certificates from national bodies outside of the EU that are responsible for radio frequency spectrum management. Certification can be obtained by MIRA for Vehicle and Component Manufacturers quickly and cost effectively

Directive 89/336/EEC (Truck, Bus & Off-Highway)
Directive 2004/104/EC (Road Vehicle)
Directive 95/56/EC (Security Systems)
Worldwide Radio Type Approval

Accreditations

UKAS accredited to ISO 17025
EMC Competent Body (appointed by DTi)
Technical Service to UK Vehicle Certification Authority
Radio Communications Agency Approved Test House

Test Laboratory Capability

Our test facilities operate on varying shift patterns to maximize customer flexibility and test capacity. They are all equipped with compressed air (to operate pneumatic actuators) and fibre optic interfaces for equipment control. All laboratories are secure environments ensuring confidentiality for all customers.