ETSI EN 300 328 V2.2.2: Compliance for 2.4 GHz ISM Band Devices

ETSI EN 300 328 V2.2.2 provides the technical framework for ensuring that wideband data transmission systems operating in the 2.4 GHz ISM band meet regulatory requirements. It is an essential standard for manufacturers of devices using Wi-Fi, Bluetooth, BLE, , LoRa, Zigbee, and other similar technologies. By adhering to this standard, manufacturers can demonstrate compliance with the Radio Equipment Directive (RED) 2014/53/EU and maintain device interoperability within crowded wireless environments.

Technical Overview of ETSI EN 300 328 V2.2.2

Scope

The standard applies to wideband data transmission systems operating in the unlicensed 2.4 GHz ISM band. Its primary focus is on enabling coexistence between devices by regulating their emission characteristics and medium access mechanisms.

Key Features:

• Frequency Range: 2.4 GHz to 2.4835 GHz.
• Device Categories:
• Adaptive Devices: Employ spectrum access techniques like Listen Before Talk (LBT) or Detect and Avoid (DAA) to dynamically manage channel usage.
• Non-Adaptive Devices: Operate without spectrum sensing mechanisms and must comply with stricter limits on duty cycle and medium utilization.
• Frequency Hopping Spread Spectrum (FHSS) and non-FHSS systems.
• Technical Requirements:
• RF Output Power (≤ 20 dBm)
• Medium Utilization Factor
• Duty Cycle and Tx-Gap Requirements
• Spurious and Out-of-Band Emissions
• Adaptivity and Utilization requirements do not apply for devices operating at <10dBm E.I.R.P.

Applications Across Industries

The scope of ETSI EN 300 328 extends across various industries, enabling effective wireless communication and regulatory compliance:

• Internet of Things (IoT): Supports diverse use cases in industrial, home, and healthcare environments.
• Consumer Electronics: Ensures compliance for smart home products, wireless audio devices, and wearables.
• Automotive Applications: Enhances communication reliability in vehicle-to-everything (V2X) systems.
• Healthcare: Facilitates reliable operation for 2.4 GHz ISM band devices in wireless medical devices.

Wi-Fi, Bluetooth, Bluetooth Low Energy, LoRa, and Zigbee Regulatory Compliance Testing

Achieving compliance for 2.4 GHz ISM band devices requires adherence to ETSI EN 300 328's rigorous standards. Comprehensive testing and validation are critical for verifying that devices meet regulatory requirements.

Technical Requirements and Testing for ETSI EN 300 328 Compliance

Core Technical Parameters

1. RF Output Power
• The standard restricts maximum RF output power to 20 dBm EIRP, ensuring devices do not dominate shared spectrum channels.
• Devices with adaptive features must dynamically adjust power output to minimize unnecessary interference in low-utilization scenarios.
2. Medium Utilization and Duty Cycle
• Non-adaptive devices must not exceed a medium utilization factor of 10%, defined as a product of duty cycle and output power. This limitation prevents excessive occupation of channel resources.
3. Spectrum Access Mechanisms
• Adaptive devices must implement LBT or DAA mechanisms to detect and avoid interference before initiating transmission. For instance, LBT requires a Clear Channel Assessment (CCA) to ensure the channel is unoccupied.
• DAA mechanisms can blacklist frequencies based on interference levels, ensuring optimal channel use.
4. Spurious and Out-of-Band Emissions
• The standard imposes strict limits on emissions outside the allocated band to reduce the risk of interference with adjacent spectrum users. These emissions must be validated through conducted and radiated testing methodologies.

Testing Requirements

ETSI EN 300 328 v2.2.2 compliance relies heavily on structured testing processes designed to evaluate device performance against environmental and technical benchmarks.

Environmental Testing

Devices are evaluated under standard environmental conditions (15°C to 35°C, 20% to 75% relative humidity), also defined as normal and extreme operating conditions and manufacturer-declared extreme operating profiles.

Conformance Testing

• Output Power Measurement: RF power is measured using fast-response sensors to capture burst transmissions accurately. Results are benchmarked against the 20 dBm limit, factoring in antenna gain.
• Duty Cycle and Medium Utilization: Non-adaptive devices undergo cycle analysis to verify compliance with utilization limits. Testing is conducted over observation periods specified in the standard.
• Spectrum Access Validation: Adaptive devices must demonstrate functional LBT or DAA mechanisms, including successful Clear Channel Assessments and frequency blacklisting behaviors under interference.
• Emission Testing: Spurious and out-of-band emissions are assessed using conducted and radiated methods, ensuring adherence to permissible thresholds.

Practical Guidance for Manufacturers

Key Steps to Achieve Compliance

1. Identify Applicability
   1. Determine whether your device is classified as adaptive, non-adaptive, FHSS, or non-FHSS. This will dictate the specific compliance requirements your product must meet under ETSI EN 300 328..
2. Prepare for Testing
   1. Before initiating formal testing, verify that your Wi-Fi, Bluetooth, Zigbee, or 2.4 GHz ISM band devices operates as intended under the manufacturer-declared settings and specifications. Pay particular attention to ensuring you have access to the PHY layer of the radio to control critical parameters such as:
      1. Data rates
      2. Modulation schemes
      3. Channel selectivity
      4. Frequency and transmission power
         1. Access to these parameters is crucial for proper configuration during testing and for achieving compliance with ETSI EN 300 328 requirements.
3. Engage Accredited Testing Services
   1. Work with certified testing laboratories that specialize in ETSI EN 300 328 v2.2.2 compliance. Accredited labs provide expert guidance, perform comprehensive tests, and ensure results align with regulatory standards.
4. Laboratory Equipment Inquiry: Ensure the test facility is equipped with an R&S TS8997 testing system or an equivalent advanced testing setup specifically designed to meet the stringent evaluation requirements of ETSI EN 300 328. Such systems are critical for precise measurement of RF parameters, emissions, and spectrum access mechanisms, ensuring accurate and reliable compliance results.
5. Compile Results
   1. Collect and organize all test data from each discipline (e.g. product safety, EMC/EMI, etc.) into the Technical Regulatory File (TRF).

Frequently Asked Questions

Speak Directly with an RF Compliance Engineer

ETSI EN 300 328 compliance is more than just a European requirement, it can be your gateway to multiple markets. A consultation with Intertek’s RF compliance experts will help you:

• Understand the technical parameters and compliance pathways for your device, including RF output power, medium utilization, duty cycle, and spectrum access mechanisms.
• Gain clarity on how ETSI EN 300 328 requirements apply to your product category, adaptive, non-adaptive, FHSS, or non-FHSS, and the technical benchmarks your device must meet.
• Learn how ETSI compliance can align with other countries’ regulatory frameworks, enabling you to reuse testing results for broader certifications.

Book your consultation with an RF engineer now and gain the clarity and confidence needed to meet regulatory standards and expand your market access.