SIST ETS 300 487:2000

SIST ETS 300 487:2000 is the Slovenian adoption of ETS 300 487 from ETSI, covering radio frequency specifications for receive-only mobile earth stations (ROMES) operating in the 1.5 GHz band and providing data communications. It gives a common basis for checking unwanted RF emissions from ROMES equipment used in the Land Mobile Satellite Service (LMSS), mainly for manufacturers, test laboratories, and approval bodies.

What does SIST ETS 300 487:2000 specify?

SIST ETS 300 487:2000 specifies RF requirements for ROMES operating above 30 MHz, including the bands used for LMSS space-to-earth reception. The standard is focused on limiting interference to radio services; EMC and safety are outside its scope.

The document is organized into scope, normative references, definitions and abbreviations, test conditions, and RF emission limits, followed by two normative annexes. Annex A sets the environmental test conditions, and Annex B gives the RF emissions test procedure.

What are the key requirements of SIST ETS 300 487:2000?

Scope and applicability

Clause 1 limits SIST ETS 300 487:2000 to ROMES terminals that operate in the LMSS bands 1 525 MHz to 1 544 MHz and 1 555 MHz to 1 559 MHz. It also notes that ROMES may be portable equipment or vehicle-installed equipment, often with several modules including a user display or control interface. In practice, this tells the reader which terminals and operating bands must be checked against the RF limits.

Test conditions and reporting

Clause 4 requires the manufacturer to state the nominal and extreme operational power supply voltages. The test report must include the test results, all operating parameters and conditions, and the value of the highest frequency conversion oscillator. This matters because the test setup has to match the declared operating range and the report has to show exactly how the measurements were made.

Clause 4 also allows the use of Special Test Equipment (STE) supplied by the manufacturer or system provider. The STE must let the ROMES tune to every channel in its operating band so that spurious emissions can be measured, and any effect of the STE on the measured parameters must be stated. The Equipment Under Test (EUT) must include all units needed for intended operation.

RF emission limits and verification

Clause 5 sets radiated power limits, including the antenna, to protect terrestrial and satellite radio services. The limits are given in table 1 across several frequency ranges, with a tighter limit in the LMSS operating band. For the reader, this means emissions have to be checked not only in the wanted band but across the wider radio spectrum where spurious radiation can occur.

The same clause says RF tests shall use the environmental conditions in Annex A and the procedure in Annex B. It also requires testing up to at least the 10th harmonic of the highest frequency conversion oscillator or ten times the highest operational frequency, whichever is greater. That requirement pushes the test far enough upward to catch unwanted harmonic products.

Measurement method

Annex B requires a test arrangement with substitution antennas, test antennas, post-test amplification, and spectrum analyzers. The ROMES is measured in normal operating mode, with data received, while tuned to the lowest, centre, and highest operating frequencies and with both vertical and horizontal polarization. The procedure searches for the maximum emission level by adjusting antenna height and rotating the EUT, then uses substitution to determine EIRP.

What terms does SIST ETS 300 487:2000 define?

• Operating frequency band - the frequency bands over which the ROMES can operate.
• EIRP (Equivalent Isotropically Radiated Power) - the radiated power level used to express the emission limits.
• EUT (Equipment Under Test) - the complete ROMES configuration being measured.
• STE (Special Test Equipment) - manufacturer-supplied equipment needed to put the ROMES into the right test mode.
• LMSS (Land Mobile Satellite Service) - the satellite service under which the ROMES operates.
• ROMES (Receive-Only Mobile Earth Station) - the receive-only mobile terminal covered by the standard.
• PE (Portable Equipment) and IE (Installed Equipment) - the two configuration types mentioned for ROMES terminals.

Who uses SIST ETS 300 487:2000?

Manufacturers of mobile satellite terminals use SIST ETS 300 487:2000 when designing ROMES equipment and defining the test mode needed for measurements. RF test laboratories use it to measure unwanted emissions and prepare the test report. Conformity assessment bodies, regulators, and system providers use it to check whether a ROMES terminal fits the expected LMSS RF limits and test setup.

What changed in SIST ETS 300 487:2000 from the previous edition?

SIST ETS 300 487:2000 is identical to ETS 300 487 E1:1996-06.

Which standards are used with SIST ETS 300 487:2000?

The standard cites the ITU Radio Regulations, which provide the frequency allocation framework for the LMSS bands used by ROMES. It also cites ETS 300 133-5 (1992), which provides the receiver conformance specification that Annex B uses as the basis for its measurement approach.

What does the SIST ETS 300 487:2000 document contain?

The document contains a table of RF emission limits, with frequency ranges and measurement bandwidths used to check unwanted radiation. Annex A gives the environmental test conditions for temperature, humidity, and declared supply voltages. Annex B gives a step-by-step RF emissions test method, including the required apparatus, EUT configuration, antenna orientation, height scanning, rotation of the EUT, and substitution measurements for EIRP.

It also includes two measurement arrangements shown as figures, one for the initial search for emissions and one for the substitution method. A far-field distance condition is stated for the antenna setup, so the measurements are taken in a valid radiating region. In practice, these contents support product design checks, laboratory testing, certification work, and audit or procurement verification of ROMES terminals.