Traffic signals

Alleviating traffic congestion remains a top priority for the city’s Transportation Department. One way to do that is to adjust the timing of red and green lights based on traffic conditions. City staff continue to make progress on connecting the city’s traffic signals to a high-speed fiber network. Before this network was available, the signals relied on wireless connectivity, which was unreliable and unable to carry the amount of data needed for the signals to achieve peak performance. Using this high-speed fiber network allows more data to travel to and from each signal, which, in turn, allows for better real time adjustments to signal timing. 

Bluetooth devices

In addition to connecting traffic signals to a new underground high-speed fiber network, staff have completed work to connect 37 Bluetooth readers to the high-speed system. These readers are attached to traffic signals at 37 of the city’s busiest intersections. The Bluetooth technology can measure the flow of traffic between traffic signals and alert staff if there’s unexpected slowing. For example, if there is a delay due to a traffic accident or construction, staff can make adjustments to the signal timing in the area to get cars moving again. This system has just come online.

California Department of Transportation coordination

One challenge in coordinating traffic signals to move cars more efficiently through the city is that Caltrans controls traffic signals near freeway onramps and offramps. If these signals are not in sync with the timing of city-controlled signals, backups can occur.

Three critical Caltrans-controlled traffic signals are now being timed to coordinate with city signals. These are at El Camino Real and state Route 78, Palomar Airport Road and I-5, and Carlsbad Village Drive and I-5. 

Staff are now working with Caltrans to coordinate the timing of signals at Cannon Road and I-5 and at Tamarack Avenue and I-5. The signal at Poinsettia Lane and I-5 does not have the ability to be programmed, but staff are working with Caltrans to see if that can be added.

New high-speed network

A public-private partnership with the communications infrastructure company Crown Castle enabled the city to utilize a high-speed fiber network to increase the performance of traffic signals. Before this network was available, the signals relied on wireless connectivity, which was unreliable and unable to carry the amount of data needed for the signals to achieve peak performance.

The Crown Castle fiber network allowed signals to use fiber instead of a wireless connection for the final leg of data transmission to and from the city’s traffic management center. The signals still use wireless signals for part of this journey.

A new agreement approved by the City Council on Dec. 12, 2023, with Netly Fiber Holdings, another communications infrastructure company, will provide access to additional high-speed fiber along Rancho Santa Fe Road in exchange for the use of the city’s existing conduit. This additional capacity will enable more of the transmission to be connected via fiber optics, which will provide more reliable service. For example, wireless transmitters often need to be reset, which requires a city staff person to travel to the site and manually perform the reset. With the new fiber installation with Netly, these resets in the field will no longer be needed.

This partnership could be expanded to other areas of the city as Netly expands its high-speed network.