As the world embraces the era of 5G technology, it is essential to understand the different frequency bands allocated for its implementation. The International Telecommunication Union (ITU) has classified 5G into three frequency bands: low, mid, and high. This article explores the significance of these frequency bands and their relevance to signal blocking devices used in exam settings.

1: The Three 5G Frequency Bands

According to the ITU, the three 5G frequency bands are as follows:

  1. Low Frequency Band (700MHz~3.8GHz):
    This band is suitable for long-range coverage and provides better penetration through obstacles. It is widely adopted in China and other countries for 5G implementation.
  2. Mid Frequency Band (3.8GHz~24GHz):
    The mid-frequency band offers a balance between coverage and capacity. It is commonly used for 5G deployment in various regions, including China.
  3. High Frequency Band (24GHz~100GHz):
    The high-frequency band provides high data rates but has limited coverage due to its shorter range. Only a few countries, mainly in Europe and America, utilize this band for 5G.

2: Signal Blocking Devices and 5G Frequency Bands

Signal blocking devices play a crucial role in maintaining exam integrity by preventing unauthorized communication during exams. These devices are designed to block specific frequency bands, including those used by 5G networks.

However, it is important to note that most signal blocking devices currently available in the market focus on blocking the low and mid-frequency bands of 5G. The reason behind this is the limited usage and adoption of the high-frequency band (24GHz~100GHz) in most countries, including China.

3: The 4.9G Frequency Band and Signal Blocking Devices

The 4.9G frequency band (4800MHz~4960MHz) has been allocated to China Mobile and China Broadcasting. However, the usage and popularity of this band are significantly low. Only a few specialized locations in China utilize the 4.9G band for private network communication.

While some signal blocking devices claim to support the 4.9G frequency band, many of them do not possess the capability to block signals within this range. The characteristics of the 4.9G band, including its higher frequency and significant signal transmission errors, limit its practical usage to indoor signal coverage.

4: Future Outlook and Considerations

Considering the current development trends, it is unlikely that the 4.9G frequency band will gain widespread adoption in China in the next few years. Therefore, the absence of signal blocking modules for this band in most devices does not compromise the effectiveness of 5G signal blocking in exam settings.

However, customers who anticipate the future deployment of the 4.9G band may request signal blocking devices with modules specifically designed for this frequency range. This proactive approach ensures preparedness for any potential upgrades or changes in the future.


Understanding the different frequency bands of 5G and their relevance to signal blocking devices is crucial in maintaining exam integrity. While the low and mid-frequency bands are widely adopted for 5G implementation, the high-frequency band and the 4.9G band have limited usage and popularity. Signal blocking devices without 4.9G blocking modules still effectively prevent 5G signal interference in exam settings. However, customers with future considerations may opt for devices equipped with 4.9G signal blocking capabilities.