Time delay detection and tracking problems have been investigated in previous papers. The approach used is applicable to many problems. In those papers, a first-order Markov process was assumed for the signal parameter (time delay) dynamic model and a constant signal parameter value was assumed within a block, or processing unit of time. A performance degradation is incurred when the signal parameter value is nearly constant-rate. Also, crossing signal parameter values from different signals cannot be tracked. The detector-trackers will switch signals. To combat these difficulties, the signal parameter dynamic model is assumed to be a second-order Markov process, and signal parameter rate of change information is computed within a block. A rate-aided multisignal detection and tracking system is developed with these assumptions. >