We all know the frustration of hearing a TTC announcement indicating that a signal-related problem is causing a delay on the subway. 

Luckily, the TTC is promising that Toronto's subway will experience fewer delays of this kind thanks to a recent extension of the Automatic Train Control (ATC) signaling system. 

"A signaling system monitors the position of trains, allows coordinated movement and informs transit control where trains are on the line at any time," notes a video introducing the new system back in 2014. 

The previous signaling system — which is still used on most of the subway and is often the cause of delays — uses lights and signals to determine where all the trains are in the tunnels. 

"The current system is approaching 60 years-old in some areas. Because of its age, there are often failures which cause delays," the video explains.

ATC technology was introduced in Toronto almost six years ago now, but it takes time and money to implement system-wide. 

On Sunday, the TTC announced that the ATC system had been extended to Queen Station. 

#TTC crews recently extended the ATC signaling system to Queen Station. This means faster, more reliable service with fewer signal-related delays on Line 1’s downtown U. For more on ATC signalling: https://t.co/ti9Uo8w1tl

— TTC Customer Service (@TTChelps) March 4, 2020

"ATC utilizes Communication Based Train Control technology, which is a signalling system that communicates with transit control more efficiently," the video explains. 

"It is a signalling system which monitors trains more accurately and will eventually make the whole system more reliable."

The ATC system also has several other benefits, such as increased safety, travel time improvements and lower operating costs. 

"Last month, the #TTC extended subway operations on Automatic Train Control (ATC) to Queen Station,"  Toronto mayor John Tory wrote of the announcement on Twitter yesterday, "this means more than half of Line 1 will be using this modernized signalling to ensure that we improve service and increase reliability."