DFS Test Prototype

This topic describes the certified modules that are available in the Sample Store on the Tuya Developer Platform.

This module is used for dynamic frequency selection (DFS) testing as part of 5G Wi-Fi certification. The module is flashed with dedicated DFS test firmware. A soldered RF cable (SMA connector) is attached to the module and connected to a spectrum analyzer or another test device. The module has 3.3V, GND, RX, and TX pins brought out. You can connect the module to the computer through a USB to TTL converter and fix the frequency with testing software or commands.

DFS test items

In CE/FCC/SRRC certification testing, DFS is a critical compliance and safety requirement for wireless devices. DFS testing primarily applies to wireless devices operating in the 5 GHz band, which may share frequency band resources with radar systems. The test requires the device to monitor radar signals in real-time within its operating frequency band. Take immediate avoidance measures upon radar detection, switch to another available channel, or reduce transmission power. This can prevent interference with radar systems, ensuring the normal operation of critical services such as aviation and meteorological radar.

The primary purpose of DFS testing is to ensure the harmonious coexistence of the electromagnetic environment between wireless communications and radar systems. Through rigorous DFS testing, the wireless device’s anti-interference capability and intelligent frequency switching mechanism can be effectively validated. This ensures that in real-world applications, the device will not cause disruption due to erroneous detection or missed radar signals. It avoids unnecessary channel switches that degrade connectivity, in order to safeguard user experience and protect critical radar systems. This is also an important prerequisite for products to obtain CE and FCC certifications.

Set up a test environment

A controlled lab environment must simulate real-world complex electromagnetic conditions.

1. Use a signal generator to simulate radar signals of different types and strengths, covering various common radar operating frequency bands and modulation methods.

2. Configure a spectrum analyzer to monitor the response of wireless devices to radar signals in real time, and capture the device’s channel switching, power adjustment, and other actions.

3. Be equipped with a shielded room or anechoic chamber to isolate external electromagnetic interference and ensure the accuracy and reliability of test data.

4. Place the test sample in the shielded room, and gradually adjust the simulated radar signal parameters according to the standard test process to comprehensively evaluate the DFS performance of the device.

   

CE

• Reference standard: ETSI EN 301 893

• Download: ETSI EN 301 893 V2.2.1 (2024-11)

FCC

• Reference standard: FCC Part 15E

• Download: FCC Part 15E

State Radio Regulation of China (SRRC)

• Reference standard: Notice of the Ministry of Industry and Information Technology on strengthening and standardizing radio management in the 2400 MHz, 5100 MHz, and 5800 MHz frequency bands (Ministry of Industry and Information Technology Wu [2021] No. 129)

For more information about the testing software, see Testing Software Download.