Uplink & Downlink

Uplink and downlink, also called upload and download, refers to the two-way communication between a cell tower and your phone.

  • Downlink definition – signal coming from a cell tower to your cellular device
  • Uplink definition – signal leaving your cellular device and going back to a cell tower

Most of us have experienced cell phone conversations when you can hear the other person but they can’t hear you or vice versa. A disruption in downlink or uplink in cellular communication causes this issue. Years ago, this was especially true because 3G cellular signal was comprised of two uplink and downlink frequency bands, 850 and 1900 MHz, one for uplinking (talking) and the other for downlinking (listening). To gain a better understanding, let’s look at how the technology works.

Mobile phones typically utilize a two-way connection consisting of downlink and uplink (the connection from the user device to the server) which is asymmetrical - that is, the downlink is much faster than the uplink.

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