Recommendation itu-r sm. 1538-1 Technical and operating parameters and spectrum requirements for short range radiocommunication devices




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4.2 Radiated power or magnetic field strength


The radiated power or H-field strength limits mentioned in Recommendation CEPT/ERC/REC 70-03 are the required values to allow satisfactory operation of SRDs. The levels were determined after careful analysis within ETSI and ERC and are dependent on the frequency range and the applications chosen. The H-field strength/power levels vary between 7 dB(A/m) at 10 m and 8 W.

4.3 Transmitter antenna source


Basically three types of transmitter antennas are used for SRDs:

– integral (no external antenna socket),

– dedicated (conformity assessment type approved with the equipment),

– external (equipment type approved without an antenna).

Only in exceptional cases external antennas could be used which will be mentionned in the appropriate Annex to Recommendation CEPT/ERC/REC 70-03.

4.4 Channel spacing


Channel spacings for SRDs are defined according to the needs of the different applications. They may vary between 5 kHz and 200 kHz or in some cases even “no channel spacing – whole stated frequency band may be used” apply.

4.5 Duty cycle categories


EN 300 220-1 V1.3.1 defines the duty cycle as follows:

For the purpose of the present document the term duty cycle refers to the ratio of the total on time of the “message” to the total off time in any one-hour period. The device may be triggered either automatically or manually and depending on how the device is triggered will also depend on whether the duty cycle is fixed or random.

For software controlled or preprogrammed devices, the manufacturer shall declare the duty cycle class or classes for the equipment under test.

For manually operated or event dependant devices, with or without software controlled functions, the manufacturer shall declare whether the device once triggered, follows a preprogrammed cycle, or whether the transmission is constant until the trigger is released or manually reset. The manufacturer shall also give a description of the application for the device and include a typical usage pattern. In the case of manually operated devices, the typical usage pattern as declared by the manufacturer shall be used to determine the duty cycle and hence the duty cycle class.

Where an acknowledgement message is required, the additional transmitter “on” time shall be included and declared by the manufacturer.

For software controlled or preprogrammed devices the maximum transmitter “on” time and minimum “off” time are given in Table 11.

TABLE 11





Name

Transmitting time/full
cycle
(%)


Maximum transmitter “on” time(1)
(s)


Minimum transmitter “off” time(1)
(s)


Explanation

1

Very low

 0.1

0.72

0.72

For example, 5 transmissions of 0.72 s within one h

2

Low

 1.0

3.6

1.8

For example, 10 transmissions of 3.6 s within one h.

3

High

 10

36

3.6

For example, 10 transmissions of 36 s within one h.

4

Very high

Up to 100





Typically continuous transmissions but also those with a duty cycle greater than 10%.

(1) These limits are advisory with the view to facilitating sharing between systems in the same frequency band.


5 Administrative requirements

5.1 Licensing requirements


Licensing is an appropriate tool for administrations to regulate the use of radio equipment and the efficient use of the frequency spectrum.

There is a general agreement that when the efficient use of the frequency spectrum is not at risk and as long as harmful interference is unlikely, the installation and use of radio equipment can be exempted from a general licence or an individual licence.

In general the CEPT administrations apply similar systems of licensing and exemption from individual licensing. However, different criteria are used to decide whether radio equipment should be licensed or exempted from an individual licence.

Recommendation CEPT/ERC/REC 01-07 lists harmonized criteria for the administrations to decide whether an exemption of individual licensing should be applied.

SRDs are generally exempted from individual licensing. Exceptions are stated in the annexes and Appendix 3 of Recommendation CEPT/ERC/REC 70-03.

When radio equipment is subject to an exemption from individual licensing, anyone can buy, install, possess and use the radio equipment without any prior permission from the administration. Furthermore, the administration will not register the individual equipment. The use of the equipment can be subject to general provisions.


5.2 Conformity assessment, marking requirements and free circulation


In 1991, the ERC adopted Recommendation T/R 71 03, which dealt with the mutual recognition of test reports and was applicable to radio equipment for non-public land mobile networks. The scope of this Recommendation was broadened in the revised version of 1994 being Recommendation ERC/REC 01-06 “Procedure for mutual recognition of type testing and type approval for radio equipment”. This Recommendation is applicable to all kinds of radio equipment and all international standards adopted within the CEPT/ERC can be used as a basis for conformity assessment. This Recommendation aims at removing the requirement for testing the equipment in every country, but still includes the requirement to apply for conformity assessment in every CEPT country.

Further, ERC has adopted Decision CEPT/ERC/DEC/(97-10) “Decision on mutual recognition procedures including marking of conformity assessment of radio and radio terminal equipment”. This Decision (including the Decisions on the adoption of harmonized standards) will set the framework for CEPT wide collaboration in this field.

The purpose of marking an equipment is to indicate its conformance to relevant EC Directives, ERC Decisions or Recommendations and national regulations.

In almost 100% of cases, requirements for marking and labelling of approved and licensed equipment is set in national law. Most administrations require at least that the logo or name of the approval authority is shown on the label, along with the approval number which may also indicate the year of approval.

Recommendation CEPT/ERC/REC 70-03 recommends three different possibilities of marking and free circulation for SRDs dependent on the conformity assessment used.

For EEA member countries a fundamental change to the regulations for conformity assessment, marking, placing on the market and free movement of SRDs has taken place when the R&TTE Directive came into force on 8 April 2000 (see Section 7).


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