ICTO Tips – What are Wi-Fi Channels and how does it affect Wi-Fi connection
ICTO小貼士 - 甚麼是無線網路頻道及其如何影響無線連接
Wireless networks are divided into multiple independent frequency bands such as 2.4 GHz and 5 GHz. Each frequency bands is divided into several channels. Each country or region has formulated its own policies on how to use frequency bands such as the maximum transmission power and bandwidth.
The 2.4 GHz band provides the most coverage but transmits data at slower speeds. Wireless range decreases as frequency increases because higher frequencies cannot penetrate solid objects like walls and floors. However, higher frequencies allow data to be transferred faster than lower frequencies, so higher frequencies like 5GHz allow you to upload and download files faster than 2.4GHz.
Compared to 2.4GHz, 5GHz will give you more signal strength and faster speeds in a shorter range. If you are able to use 5GHz is your best choice to take advantage of higher speeds. Similarly, if you’re doing a lot of high-bandwidth activities online, such as online classes or video conferencing, it is best to use this frequency and move as close as possible to the Wireless LAN Access Point.
2.4 GHz Channel Allocations
NOTE: Marked in accordance with the frequency bands permitted by the Macao SAR Regulations for Radiocommunication Services, details of which can be found on the website of the Macao Post and Telecommunications Bureau.
5 GHz Channel Allocations
NOTE: This Frequency Allocation Chart is for reference only. Details can be found at Ministry of Industry and Information Technology of the People’s Republic of China website, Macao Post and Telecommunications Bureau website and Hong Kong SAR OFCA website.
Use Macau 5 GHz Channel Allocations as example, the permitted wireless frequency bands are relatively wide which include 5150 – 5350 MHz (Channel 36 to 64), 5470 – 5725 MHz (Channel 100 to 144), 5725 – 5850 MHz (Channel 149 to 165), and so on.
For China, the currently available frequency bands are 5150 – 5350 MHz (Channel 36 to 64) and 5725 – 5850 MHz (Channel 149 to 165).
Some of the devices that manufactured by China may not support 5150-5350 MHz frequencies due to production date, operations system or other hardware factors. And probably cause Wi-Fi signal cannot be search, connection disconnected continuously, or continually fighting with slow network speeds, etc.
- Check the product specification and confirm whether the Wi-Fi channel compatibility which is within 2.4 GHz and 5 GHz Wi-Fi channel allocation range in Macau before purchasing the device.
- For the devices that manufactured by China, please try to update the latest operating system provided by the official website.
- Some China brand such as Xiaomi, Huawei, OPPO, or Realme provide region setting. Try to change region setting to Macau SAR, and maybe able to receive 5470 – 5725 MHz (Channel 100 to 144) Wi-Fi signal. Changing region setting will not affect the normal operation of the device.
ICTO Help Desk
| Location : | Room 2085, 2/F, Central Teaching Building (E5) eMap |
| Telephone : | 8822 8600 |
| Email : | icto.helpdesk@um.edu.mo |
無線網路劃分了多個獨立的頻段（如2.4 GHz和 5 GHz），每個頻段又劃分為若干頻道。每個國家或地區自行制定了政策訂出如何使用這些頻段，例如最大的發射功率和頻帶寬度等。
2.4 GHz 頻段提供最大的覆蓋範圍，但傳輸數據的速度較慢。無線範圍隨著頻率的增加而減小，因為更高的頻率無法穿透牆壁和地板等固體物體。然而，較高的頻率比較低的頻率能更快地傳輸數據，因此像 5GHz 這樣較高的頻率比 2.4GHz 更快地上傳和下載文件。
與 2.4GHz 相比，5GHz 在較短的範圍內為您提供更強的信號和更快的速度。如果您能夠使用更高速度的5GHz，這會是最佳選擇。同樣，如果您正在進行大量高帶寬活動，例如線上課程或視像會議，最好使用此頻率並儘可能靠近無線網接入點。
2.4 GHz頻道分配
注意: 頻道分配根據澳門特別行政區無線電通訊服務法規所准許的頻帶進行標示，詳細內容可到澳門郵電局網頁查詢。
5 GHz 頻道分配
注意: 本頻率劃分圖只供參考，詳情可參閱中華人民共和國工業和信息化部網頁、澳門郵電局網頁及香港通訊事務管理局辦公室網頁 。
以澳門地區 5 GHz 頻道分配為例，准許的無線數據通訊頻帶比較寬廣，包括： 5150-5350 MHz（36 至 64 頻道）、5470-5725 MHz（100 至 144 頻道）、5725-5850 MHz（149 至165 頻道）等。
而現時國內5 GHz可使用頻道為: 5150 – 5350 MHz 頻帶（36 至 64 頻道），5725-5850 MHz（149 至165 頻道）等。當中由於設備的生產日期、操作系統或其他硬件因素，部分國內行貨設備可能不支持 5150-5350 MHz 頻帶（36 至 64 頻道），有機會出現 Wi-Fi 信號無法搜尋、不間斷斷線，或網絡速度持續緩慢等情況。
- 在選購設備之前查閱裝置規格表，可先確認無線網路頻道的兼容性是否合適澳門2.4 GHz 和5 GHz 的頻道分配範圍內。
- 對於國內行貨設備，請嘗試更新官方提供的最新操作系統。
- 部分國內品牌例如小米、華為、OPPO或Realme等設備提供系統區域設置。可嘗試把區域設置切換為「澳門特別行政區」，或可接收5470 – 5725 MHz頻率（100至144頻道）的無線網訊號。更改區域設置不會影響設備的正常運行。
資訊及通訊科技部服務中心
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