Certification of Private Land Mobile Radio Equipment to the R&TTE Directive

Ian Weatherilt

New standards and new procedures are changing the way PMR equipment is certified. Notified bodies still play a role.

The introduction of the Radio and Telecommunications Terminal Equipment (R&TTE) Directive significantly changed the way in which telecom products are certified in the European Union (EU). This article reviews the way in which the directive is applied to radio equipment. It also highlights some of the major changes that the directive has brought to regulatory approvals of telecom systems.

The main objective of the R&TTE Directive is to harmonize the radio and telecommunications industry, and, in comparison with the old TTE directives, to simplify the conformity process (see the sidebar, "Evolution of the R&TTE Directive" at bottom). This directive, then, should reduce the time necessary for the introduction of new equipment. Manufacturers demonstrate compliance with the R&TTE Directive by complying with a set of essential requirements, which are:

• For both radio equipment and TTE: The protection of the health and safety of the user and any other persons, including the objectives with respect to safety requirements contained in Directive 73/23/EEC (Low Voltage Directive [LVD]), but with no voltage limits applying; and the protection requirements with respect to electromagnetic compatibility (EMC) contained in Directive 89/336/EEC (EMC Directive).
• For radio equipment only: Radio equipment must be constructed so that it effectively uses the spectrum allocated to terrestrial and space radio communications and orbital resources so as to avoid harmful interference.
• Additional requirements (if the commission decides to apply them to certain types of equipment): Equipment must interact via networks with other apparatus and must be able to be connected to the interfaces of the appropriate type throughout the EU; equipment must not harm the network nor misuse network resources, thereby causing an unacceptable degradation of services; equipment must incorporate safeguards to ensure that the personal data and privacy of the user and of the subscriber are protected; equipment must support certain features ensuring avoidance of fraud; equipment must support certain features ensuring access to emergency services; equipment must support certain features to facilitate its use by disabled users.

In addition, many network operators are now commercial companies. It is therefore unnecessary to regulate the use of telecom products within their network systems. Regulation becomes applicable only when aspects of the design of the system may cause harm to others. Therefore, the only requirements currently deemed essential for wired telecommunications apparatus are those for safety and EMC. The R&TTE Directive allows the use of existing harmonized standards for determining conformance with the essential requirements of the EMC and Low Voltage directives.

EMC and Safety

The existing EMC standards for information technology equipment are applied to wired systems. These standards have been published and harmonized within the EU. For radio equipment, a series of EMC standards has been developed. ETS EN 301 489-1 is the first part of a multipart European standard series covering EMC for different radio equipment and services (see Table I). EN 301 489-1 includes all the basic EMC tests that the other standards in the EN 301 489 series reference.

EN 301 489-5 covers the EMC aspects for private land mobile radios (PMRs). This standard supersedes the previous ETSI 300 279 (EMC standard for PMR and ancillary equipment [speech and nonspeech]). One major change in the new standards is the introduction of radiated immunity testing above 1 GHz. This requirement is not currently required in the generic EMC test standards such as EN 61000-6-2, the standard for industrial environments for general products.

As part of the CE marking process for electrical safety, it is now necessary to perform safety evaluation and testing for battery-powered handheld radios and phones. The safety evaluation and testing are also required for telecommunications equipment that requires low-voltage dc power, such as computer modems. Although shock hazards may not be an issue, the risk of fire (and other non-electric-shock) hazards must still be assessed. For most low-voltage dc telecommunications equipment, the requirements of EN 60950 are applicable. For radio equipment, EN 60215 (safety requirements for radio-transmitting equipment for broadcast radio systems) is one of the few product-specific standards. In cases for which there is no product-specific standard, as is the case for PMR equipment, the following standards can be considered:

• EN 60065—Audio, video, and similar electronic apparatus.
• EN 60335-1—Electrical household apparatus.
• EN 61010-1—Measurement, laboratory, and control equipment.

Radio Testing

The approach for testing PMR equipment against Article 3.2 of the directive is well defined. A number of ETSI radio standards have been retained under the R&TTE Directive. However, the scopes of these standards are being reduced to encompass only requirements relating to efficient use of the frequency spectrum, and new versions of many existing ETSI standards have already been developed. For PMR equipment, EN 300 086-2 represents an example of these new scaled-down standards. This standard specifically addresses essential requirements under Article 3.2 of the R&TTE Directive.

In EN 300 086-2, two sets of test suites are defined: essential radio test suites and other radio test suites. Under Article 3.2, only essential radio test suites need to be performed for radio equipment. The essential radio test suites in EN 300 086 relate to the following tests:

• Frequency error (EN 300 086-1, clause 8.1.2).
• Carrier power (conducted) (EN 300 086-1, clause 8.2.2).
• Effective radiated power (EN 300 086-1, clause 8.3.2).
• Maximum frequency deviation (EN 300 086-1, clause 8.4.1.2 and clause 8.4.2.2).
• Adjacent channel power (EN 300 086-1, clause 8.5.2 shall be carried out).
• Spurious emissions (EN 300 086-1, clauses 8.6.2 and 8.6.3, or clause 8.6.4).
• Intermodulation attenuation (EN 300 086-1, clause 8.7.2).
• Transient frequency behavior of the transmitter (EN 300 086-1, clause 8.8.2).

The other radio test suites in EN 300 086-2 are related more to receiver performance of the radio equipment rather than the spectral aspects. These tests include:

• Maximum usable sensitivity (speech, conducted) (EN 300 086-1, clause 9.1.2).
• Maximum usable sensitivity (speech, field strength) (EN 300 086-1, clause 9.2.2).
• Cochannel rejection (EN 300 086-1, clause 9.4.2).
• Adjacent channel selectivity (EN 300 086-1, clause 9.5.2).
• Spurious response rejection (EN 300 086-1, clause 9.6.2).
• Intermodulation response rejection (EN 300 086-1, clause 9.7.2).
• Blocking or desensitization (EN 300 086-1, clause 9.8.2).
• Spurious radiations (EN 300 086-1, clauses 9.9.2, 9.9.3, or 9.9.4).
• Desensitization and sensitivity (duplex) (EN 300 086-1, clauses 10.1.2 or 10.1.3).
• Spurious response rejection (duplex) (EN 300 086-1, clauses 9.6 and 10.1.2 or 10.1.3).

The other radio test suites are not essential to meeting Article 3.2 of the directive because they do not affect the effective use of the spectrum. These other radio test suites are more likely to be performed by manufacturers and suppliers to gain a market advantage or because the market demands them. Other PMR standards are listed in Table II.

At some point, specific absorption rate (SAR) requirements will come into play for PMR. Since March 2002, all mobile phones sold in the EU are required to carry information indicating the radiation emission levels they produce. To address human exposure to electromagnetic fields radiated by equipment, four standards have recently been ratified:

• EN 50357:2000, "Evaluation of human exposure to electromagnetic fields from devices used in electronic article surveillance (EAS), radio frequency identification (RFID) and similar applications."
• EN 50360:2001, "Product standard to demonstrate the compliance of mobile phones with the basic restrictions related to human exposure to electromagnetic fields (300 MHz–3 GHz)."
• EN 50361:2001, "Basic standard for the measurement of specific absorption rate related to human exposure to electromagnetic fields from mobile phones (300 MHz–3 GHz)."
• EN 50364:2001, "Limitation of human exposure to electromagnetic fields from devices operating in the frequency range 0 Hz to 10 GHz, used in electronic article surveillance (EAS), radio frequency identification (RFID) and similar applications."

Conformity Assessment Routes

To show compliance with the essential requirements of the directive, manufacturers have a choice of conformity assessment routes. These routes are dependent on the type of equipment being certified.

Internal Production Control (Annex II). This route is available for TTE and receiving parts of radio equipment. For this route, it is the manufacturer's responsibility to assess products against the essential requirements of the directive, compile the technical documentation, and declare that the equipment complies with the essential requirements. Harmonized standards can be used if a manufacturer chooses; when they are used, they give a presumption of conformity. Internal production control is the simplest route and is applied when a product is extremely simple or harmonized standards already exist that cover the performance requirements for the product.

It should be noted that this route is not applied to those products that are radio transmitters. This route provides a means of speeding up the certification process by allowing manufacturers to perform all work internally.

The technical documentation developed by the manufacturer must enable conformity of the product to be assessed against the essential requirements. Documentation must cover the design, manufacture, and operation of the product. In particular, documentation must include:

• A general description of the product.
• Conceptual design and manufacturing drawings and schemes of components, subassemblies, circuits, etc.
• Descriptions and explanations necessary for the understanding of said drawings and schemes and the operation of the product.
• A list of the standards referred to in Article 5 of the directive, applied in full or in part, and descriptions and explanations of the solutions adopted to meet the essential requirements of the directive where such standards referred to in Article 5 have not been applied or do not exist.
• Results of design calculations made, examinations carried out, etc.
• Test reports.

Internal Production Control Plus Specific Apparatus Tests (Annex III). Available for radio equipment only, this route applies an appropriate harmonized standard. If this harmonized standard does not contain the essential radio test suites, a manufacturer must have tests specified by a notified body. It is then the manufacturer's responsibility to identify the essential radio test suites carried out, to compile the technical documentation listed in Annex II, and to declare that the equipment complies with the essential requirements.

This procedure is similar to Annex II, but is applicable only to radio transmitters. Performance requirements are defined by the use of harmonized standards. As long as a manufacturer can demonstrate that a product meets all the applicable standards, the manufacturer can again perform all the work within the company.

Technical Construction File (TCF) Route (Annex IV). This route is available for both radio equipment and TTE. A manufacturer presents a technical construction file to a notified body. This file should consist of the technical documentation listed in Annex II of the directive. In addition, for radio equipment, the file must contain the results of the essential radio test suite agreed upon previously with the notified body (as per Annex III).

The notified body then has four weeks to issue an opinion. After the manufacturer receives this opinion (or after four weeks), the manufacturer is free to place the equipment on the market. This route is normally used when no harmonized standards exist, or when the choice of appropriate standards is unclear.

The TCF route is slightly longer because the intervention of a notified body is required. However, it should be noted that the notified body is offering only an opinion. If the manufacturer does not agree with the opinion (or it is not available within four weeks), the manufacturer can place the product on the market. This flexibility supports the objective of the directive to adopt rules intended to speed up the time to market for new products.

Full Quality Assurance Route (Annex V). This route is available for radio equipment and for TTE. To follow this route, manufacturers must operate an approved quality system for design, manufacture, and final product inspection and test. A notified body must assess the system. This is a more time-consuming process, but many manufacturers use it because all certification work is within their own control. This process entails only a periodic check of the manufacturer's quality system.

The R&TTE Directive allows for liberal interpretation when determining which route to use to demonstrate compliance. It also allows a certain degree of mixing and matching of routes, depending on the type of product. With the exception of full quality assurance (Annex V), the compliance options build on one another. So Annex III (which calls for specific tests identified by a notified body) adds to Annex II (which requires internal production control and a manufacturer's declaration). Annex IV (which describes the technical construction file) builds on Annex III.

In practice, then, it should be possible to apply the principles of Annex II to aspects covered by harmonized standards, and then add to this Annex III or Annex IV for radio or nonharmonized aspects. Annex IV (TCF) is best suited for developing technologies for which harmonized standards have not been fully developed. Similar to the EMC TCF route, this option gives manufacturers more flexibility, and equipment can be tested in part to a harmonized standard, or the essential radio test suites can be developed with the involvement of a notified body. Also, like the EMC TCF route, a third-party review is required; in this case, it is the notified body's opinion.

A manufacturer always has a choice of deciding how to comply with the safety and EMC essential requirements, as outlined in the respective directives. In the case of EMC, this allows for the use of a TCF route under the EMC Directive. This choice allows manufacturers to tap into the flexibilities that the EMC TCF route provides for R&TTE EMC certification. Using the EMC TCF route provides a number of significant advantages:

• The manufacturer or supplier may choose which standards to apply (in agreement with a competent body or notified body appointed by the enforcement authority).
• Representative systems that incorporate all types of variants may be tested.
• In many cases, variants may be added to the TCF without performing full-scale retesting of the system.

It is a mandatory requirement that a competent body, appointed by a national regulatory body, assess the EMC TCF portion of the documentation. In the UK, competent bodies therefore still retain telecom and radio systems within their scope of activity.

Classification and Equipment Identifiers

The commission has defined the initial classification and equipment identifiers for the R&TTE Directive. Two classes have been defined:

• Class 1 comprises equipment that can be placed on the market and put into service without restrictions. An equipment class identifier has not been assigned to this type of equipment.
• Class 2 comprises radio equipment for which member states apply restrictions for putting into service or placing on the market under Articles 7(2) and 9(5) of the directive respectively.

Equipment that falls within Class 2 has a class identifier consisting of an exclamation mark within a circle (see Figure 1). This marking, along with the CE marking, is placed on the equipment. PMR is categorized as Class 2.6 equipment.

In consultation with the Telecommunication Conformity Assessment and Market Surveillance Committee (TCAM), the EC publishes and maintains a list of equipment that falls within the two classes. This list can be found on the R&TTE Directive Web site (http://europa.eu.int/comm/enterprise/rtte/infor.htm).

Notification

For PMR equipment, which uses nonharmonized frequency bands throughout the European community, a manufacturer or supplier (or authorized representative) must notify the national authority (for spectrum management) in the appropriate member state of an intent to place equipment on its market. The logic behind doing so is to ensure the free movement of goods within the EU.

Placing a product on the market within a member state does not mean it is to be used within the national boundaries of that member state. However, not to be able to place a product on the market is a restriction of sale. Therefore, national licensing of radios is still required, and use without licensing remains a criminal offense.

This notification must be given no less than four weeks before the product is placed on the market. The notification must provide information about the radio characteristics of the equipment (in particular, frequency bands, channel spacing, type of modulation, and radio-frequency power) and the identification number of the notified body, if applicable.

Conclusion

Since the introduction of the R&TTE Directive and development of harmonized standards covering Article 3.2 of the directive, manufacturers can self-certify for PMR equipment via Annex III (compliance certification route). The introduction of the new harmonized standards associated with Article 3.2 has reduced the required radio testing to a minimum, with only the essential radio test suites being required. However, it still may be advantageous to manufacturers to perform the receiver performance tests covered under the other radio test suites because of customer demand.

As detailed in Annex II (conformity assessment routes), technical documentation is required and plays an important part of the certification process. The documents must cover safety, EMC, and radio testing, and because of the complexities involved, a third party (notified body) can play an important role in facilitating certification. Although at first it may seem complicated to achieve all this, in reality the majority of the documentation required will already be available to manufacturers that wish to place a product on the market in the EU. It is simply a matter of marshalling it together into a single technical file. Because this is done within a manufacturer's own organization, the speed to market is now largely controlled by manufacturers and is not influenced by outside agencies. This shift for the EU regulatory regime is a significant step forward in regulatory control.

Ian Weatherilt is a senior European regulatory consultant for Technology International Inc. (Richmond, VA), a subsidiary of Technology International (Europe) Ltd. in the UK Technology International (http://www.techintl.com) is a competent body for EMC and a notified body for the Low Voltage, Machinery, and R&TTE directives. Weatherilt can be e-mailed at iweather@techintl.com.