What Is RF Output Power — RED?
RF output power measurement is the measurement in which the conductive power of the transmitter at the antenna input or the radiated power (EIRP/TRP) with the antenna is determined with the measurement settings defined in the standard.
Purpose of RF Output Power — RED
The purpose is to verify that the transmitter power does not exceed the maximum allowed in the relevant radio standard.
Which Products Is RF Output Power — RED Applied To?
- Short range devices
- Wi-Fi and Bluetooth modules
- cellular modules
- Industrial telemetry transmitters
In Which Sectors Is RF Output Power — RED Used?
Standards Related to RF Output Power — RED
- REDEU radio equipment directive test
- ETSIEuropean telecommunications standards test
- FCCUS radio and EMC regulations test
RF Output Power — RED Conditions
- Measurement type
- Conducted power (at antenna connector) or radiated power (EIRP/TRP)
- Measurement settings
- Standard defined resolution bandwidth, detector and averaging
- Channel selection
- Lower, middle and upper channels
- antenna gain
- Antenna gain is taken into account when calculating radiated power.
Equipment for RF Output Power — RED
- Spectrum analyzer or power meter
- Semi-anechoic chamber and calibrated antenna (for radiated measurement)
- Caliber attenuator and cable set
- Device test mode control interface
Sample Requirements for RF Output Power — RED
- The device should be driven at maximum power setting.
- Radiated measurement must be made if the antenna connector is not accessible
- Antenna gain and cable loss must be documented
- Measurement settings must comply with the standard
Duration of RF Output Power — RED
Days by number of channels and modes.
RF Output Power — RED Procedure
- 1The device is put into test mode at maximum power setting.
- 2Measurement settings are configured according to the standard.
- 3Power is measured in the lower, middle and upper channels.
- 4In radiated measurement, antenna orientations are scanned.
- 5EIRP or TRP is calculated.
- 6Results are compared with the limit.
RF Output Power — RED Acceptance Criteria
The acceptance criterion is the maximum output power or EIRP limit given in the applied standard.
Evaluation of Results
Conducting power and EIRP are different quantities; If antenna gain is not taken into account, the suitability will be evaluated incorrectly. For pulsed transmissions, the choice of detector and averaging changes the result significantly.
RF Output Power — RED Report
- Applied standard and type of measurement
- Device and antenna description
- Measurement settings
- Results by channel
- Measurement uncertainty
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- Radio Equipment Directive 2014/53/EU (RED)
- FCC Part 15
RF and Wireless Testing — What Does This Testing Field Cover?
The section below describes the field that the RF Output Power test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
RF and wireless testing shows that a device containing a radio uses the spectrum correctly and operates within the limits the relevant legislation allows. This family is a separate body of work from EMC: EMC addresses unwanted interference, whereas here INTENTIONAL emission is assessed.
Spectrum is a public and limited resource, and this determines the legal character of the field. A device spilling outside its permitted band or emitting excess power is not merely a technical defect but a violation that disrupts someone else's service. Radio conformity is therefore policed more strictly than other test fields and markets maintain their own national regimes.
Measurements run separately on the transmitter and receiver sides. On the transmitter side, output power, occupied bandwidth, frequency error, unwanted emissions, adjacent channel power and the power envelope are measured. On the receiver side, sensitivity, selectivity, blocking and spurious response rejection are assessed. The receiver side is often neglected, but in some bands it is a regulatory requirement.
Access protocol specific behaviours are a third axis: listen before talk (LBT), duty cycle, dynamic frequency selection (DFS) and transmit power control (TPC). These mechanisms enable spectrum sharing and it must be shown that they work correctly.
HUMAN EXPOSURE is the fourth axis and one of the most commercially critical. For devices used close to the body, SAR (specific absorption rate) is measured; for devices used at a distance, a field strength assessment is made. Limits and measurement methods vary by market; the same device is assessed separately for Europe and the United States.
Market regimes are decisive in this family and do not substitute for one another: the Radio Equipment Directive and ETSI harmonised standards in Europe, FCC authorisation in the United States (through a TCB for intentional radiators), ISED in Canada, MIC in Japan, KC in South Korea and SRRC in China each carry their own set of requirements. The same device requires a separate file for each market, and some markets impose a local representative or local testing requirement.
Module integration is the subject that raises the most questions in the field. Using a certified radio module does not automatically make the device compliant. A module certificate is valid for a defined antenna, a defined supply and defined conditions of use; if the antenna changes, the layout changes or the module is operated at a different power level, reassessment is required.
The presence of several radios in the same device (Wi-Fi + Bluetooth + cellular + NFC) gives rise to a simultaneous transmission assessment: SAR and unwanted emission measurements are made for the worst case in which the radios operate together.
Method groups in this field
Transmitter measurements
Output power, occupied bandwidth, frequency error, unwanted emissions, adjacent channel power, power spectral density.
Receiver measurements
Sensitivity, selectivity, blocking, spurious response rejection.
Spectrum sharing mechanisms
Verification of listen before talk, duty cycle, dynamic frequency selection and transmit power control.
Human exposure
SAR measurement (handheld and body-worn devices), field strength assessment, multi-radio scenarios.
Protocol conformity
Cellular network conformity testing, Bluetooth and Wi-Fi certification testing, GNSS performance.
Antenna measurements
Gain, radiation pattern, efficiency and total radiated power (TRP) measurements.
Commonly confused in this field
- Using a certified module does not automatically make the device compliant; if the antenna, layout or power level changes, reassessment is required.
- An FCC file does not replace a CE file; each market operates its own regime.
- Receiver side measurements are a regulatory requirement in some bands; measuring only the transmitter produces an incomplete file.
- SAR limits and measurement methods differ by market; a result in one market does not carry over to another.
- For devices carrying several radios the simultaneous transmission scenario must be assessed; measuring them individually is not sufficient.
- Some markets impose local testing or a local representative requirement; technical conformity alone does not secure market access.
Which decisions these results support
- Market access under radio equipment legislation
- Verification of the antenna and RF front end design
- SAR and RF exposure conformity
- Verification of module integration and the scope of reassessment
- Determining the worst case in multi-radio scenarios
Related Tests
Frequently Asked Questions About RF Output Power — RED
According to which standard is RF Output Power made?
RF Output Power is executed in scope ETSI EN 300 328 / EN 300 220 measurement sections, FCC Part 15, ETSI TR 102 273 (belirsizlik), CISPR 16-1-1 (measuring receiver), RED, ETSI and FCC. The limit values and acceptance criteria to be applied are defined in the product standard; The version valid for your product is confirmed in writing at the offer stage.
Which products does RF Output Power apply to?
Mainly applied to Short range devices, Wi-Fi and Bluetooth modules, cellular modules and Industrial telemetry transmitters. Whether your product is included in the scope is determined by examining its technical specifications and intended use.
Under what conditions is RF Output Power done?
The determining parameters are: Measurement type — Conducted power (at antenna connector) or radiated power (EIRP/TRP), Measurement settings — Standard defined resolution bandwidth, detector and averaging and Channel selection — Lower, middle and upper channels. The full terms are in the "Test Conditions" section on the page and vary depending on the product standard.
What kind of sample is needed for RF Output Power?
The device should be driven at maximum power setting., Radiated measurement must be made if the antenna connector is not accessible and Antenna gain and cable loss must be documented. The number of samples is determined according to the product standard and the scope to be reported.
How long does RF Output Power take?
Days by number of channels and modes. This duration belongs to the experiment itself; sample preparation, queuing and reporting are also evaluated. A realistic schedule for your product is given in the offer.
What is the RF Output Power result called "appropriate"?
The acceptance criterion is the maximum output power or EIRP limit given in the applied standard.