Te developed signal state prediction system, Personal Signal Assistant or PSA, produces for each signal group second-by-second prediction of two signal state switches in a full cycle: time to green (G) and time to red (R). Te 1 Hz data rate allows for quick updates and fast responses when the traffic situation changes. For example, when transit signal priority or emergency preemption calls occur, the PSA system can quickly generate the corresponding message. Te system consists of three major sub-systems: signal state data collection from