Mobile congestion is when too many devices try to connect to the same mobile network tower at the same time, causing slow data speeds, dropped calls, or failed connections. 

Think of it like a freeway at peak hour – too many cars (users) trying to go through the same lanes (network bandwidth), leading to slowdowns or blockages. 

Why does congestion occur? 

The mobile network was initially designed to make phone calls and send SMS messages. Over time, the way we use our devices has evolved leading to a steep increase in the amount of data we consume (eg. videos and social media). In fact, Australia’s data consumption is increasing by 30% annually, which is why technology upgrades are needed to meet this increased demand, and older technologies (e.g. the 3G network) have been shut down.  

Mobile towers can only handle a limited number of connections at one time, which depends on several factors. Each tower is divided into multiple cells or sectors, usually three to six, each covering a specific direction and operating on a unique frequency range to avoid interference. The more cells a tower has, the greater its capacity to support simultaneous users. Additionally, a tower’s ability to handle calls and data is determined by the spectrum and bandwidth allocated to it by the network provider. 

 Australia’s mobile network providers, Telstra, Optus, and Vodafone, operate within assigned slices of radio frequency spectrum. If too many users attempt to connect at once, the tower can become overloaded, leading to call failures, slow data speeds, and network congestion.  

When a mobile tower experiences high demand, a process known as “cell-breathing” occurs. This means the coverage area of the tower contracts as more devices connect, then expands again when demand decreases. For example, Telstra prioritises voice call quality over data usage, so users located at the edge of a tower’s coverage may experience weaker signals, dropped calls during peak times, or difficulty accessing mobile data. This effect can become more noticeable during periods of high network congestion, such as holidays, areas experiencing population growth or in emergency situations.  

Common reasons for congestions are: 

• Too many users on the same tower – Occurs in busy areas that may be experiencing rapid population growth, hosting large events or are popular holiday spots. Solutions like mobile CEL-FI extenders and antennas increase the amount of people able to access the network in the area, resulting in further congestion. 

• High data usage (streaming, video calls, downloads) – Live streaming, video calls, and large downloads consume network bandwidth, therefore the more people using data-heavy applications, the worse congestion gets. 

• Peak hour traffic – Just like roads, networks get busier at certain times of the day. These busy times often coincide when people are not working (evenings, lunch breaks, weekends).  

 **Note: while Cel-Fi extenders and antennas may boost signal strength and improve connectivity, they do not increase overall network capacity and therefore will not help with congestion. 

Signs of mobile congestion 

• Slow internet speeds (webpages taking longer than normal to load) 

• Buffering on video streaming (smart TVs, YouTube, Netflix, Zoom lagging) 

• Delayed or failed messages and calls 

• Call dropouts or “network busy” messages 

• Apps not loading properly