Radio Frequency Testing

1. What is SRRC Certification

SRRC Certification (SRMC Certification), formally known as "Radio Transmission Equipment Type Approval Certification," is a mandatory certification system established by the State Radio Regulation Committee. This certification is administered by the Radio Management Bureau of the Ministry of Industry and Information Technology (MIIT) and applies to electronic products with wireless, Bluetooth, or transmission frequency functions.

According to the "Radio Regulations of the People's Republic of China," all radio transmission equipment exported to or produced in China must undergo SRRC certification and display the radio transmission equipment type approval code. Each radio transmission equipment model is issued a unique "Radio Transmission Equipment Type Approval Certificate" and approval code (CMIIT ID). If a product undergoes changes in performance or main technical parameters, it must undergo SRRC recertification.

2. Product Scope for SRRC Certification

SRRC Certification covers all products with radio transmission functions, including but not limited to:

• Mobile Communication Devices – Mobile phones, tablets, wireless POS machines, mobile Wi-Fi hotspots, etc.
• Short-Range Wireless Devices – Bluetooth speakers, Bluetooth earphones, TWS earbuds, wireless keyboards and mice, smartwatches, etc.
• Smart Home Devices – Smart door locks, smart cameras, smart speakers, smart lighting, air conditioner remote controls, etc.
• In-Vehicle Wireless Devices – Car navigation, dashcars, car Bluetooth, car Wi-Fi, ETC on-board units, etc.
• IoT Devices – NB-IoT modules, LoRa modules, ZigBee modules, wireless sensors, smart wearables, etc.
• Wireless Audio/Video Devices – Wireless microphones, wireless earphones, wireless speakers, UAV video transmission modules, etc.

3. SRRC Certification Testing Items

SRRC certification testing is conducted by designated national laboratories according to relevant radio management requirements. Main testing items include:

3.1 Transmit Power Test

Verifies whether the device's transmit power meets national limit requirements. Different frequency bands and product types have different power limit standards. Exceeding limits may cause interference with other radio devices or violate spectrum management regulations. Testing must cover all operating frequency bands supported by the device.

3.2 Frequency Tolerance Test

Tests the stability and accuracy of the device's operating frequency, ensuring the transmit frequency is within the specified range. Frequency tolerance refers to the maximum allowable deviation between actual transmit frequency and nominal frequency. Exceeding tolerance may cause frequency interference with other users.

3.3 Bandwidth Test

Verifies whether the device's transmit bandwidth meets relevant standard requirements. Excessive bandwidth may occupy too much spectrum resources, reducing spectrum utilization efficiency; insufficient bandwidth may affect data transmission efficiency.

3.4 Spurious Emission Test

Tests for any undesired emissions generated outside the operating frequency band. Spurious emissions include harmonic emissions, intermodulation products, parasitic emissions, etc. These undesired emissions may interfere with other radio services and must be controlled within specified limits.

3.5 Modulation Characteristics Test

Verifies whether the device's modulation method, modulation depth, modulation accuracy, etc., meet standard requirements. Correct modulation characteristics are the foundation for ensuring communication quality. Different communication systems have different modulation requirements.

3.6 Power Spectral Density Test

Measures the device's energy distribution characteristics in the frequency domain, ensuring the transmitted signal does not produce excessive spectrum spread. Power spectral density testing is particularly important for digitally modulated devices, requiring out-of-band emissions to meet spectrum mask requirements.

4. SRRC Certification Process

The SRRC certification process is divided into the following main steps:

1. ①Pre-Application Preparation – Confirm whether the product falls within SRRC certification scope, prepare technical documentation including product technical specifications, circuit diagrams, block diagrams, BOM lists, and product photos.
2. ②Submit Application Materials – Submit certification application to the MIIT Radio Management Bureau, including application form, product technical materials, and business license.
3. ③Product Testing – Send samples to designated national laboratories for testing. Laboratories conduct comprehensive testing according to relevant standards and issue test reports.
4. ④Documentation Review – After the laboratory submits the test report, MIIT reviews the technical materials and test report.
5. ⑤Certificate Issuance – After passing review, the MIIT Radio Management Bureau issues the "Radio Transmission Equipment Type Approval Certificate" and approval code (CMIIT ID).

5. Certificate Management and Maintenance

Certificate Validity: SRRC approval certificates are valid for 5 years. Companies must submit extension applications before the validity period expires. After obtaining the certificate, companies can affix the certification mark on products, indicating compliance with national radio management regulations.

Change Declaration: If product performance or main technical parameters change (such as transmit frequency, power, modulation method changes), SRRC recertification is required. Minor appearance changes or changes that do not affect RF characteristics may not require recertification, but confirmation from the competent authority is needed.

Market Supervision: Products that have obtained SRRC certification are still subject to supervision and inspection by radio management departments after being sold in the market. If products are found to be non-compliant with the approved model or have quality issues, penalties such as certificate revocation or product recall may be imposed.

6. Frequently Asked Questions and Precautions

7. Summary and Recommendations

SRRC certification is the statutory market access threshold for radio transmission equipment entering the Chinese market and a necessary condition for products to be legally sold domestically. With stricter e-commerce platform supervision and more rigorous enforcement of radio management regulations, products without SRRC certification will face increasing market risks and legal liabilities.

For companies planning to sell wireless products in the Chinese market, recommendations include: Confirm early whether products fall within SRRC certification scope and plan certification timeline in advance; Choose professional laboratories and agencies with qualifications to effectively improve certification efficiency; Ensure product design meets national radio management requirements to avoid test failures due to design flaws; Monitor product changes during certificate validity period and handle change or recertification procedures in a timely manner.

Although SRRC certification involves a certain timeline and cost, it is an essential "passport" for products entering the Chinese market. Through compliant certification, companies can not only avoid legal risks and market penalties but also enhance product competitiveness, laying a solid foundation for development in the Chinese market.