A fast method for tracking multiple nonstationary tones

A row action projection technique with adaptive frequency space partitioning is used. A sample-by-sample update strategy provides a dynamic block size and allows for superresolution in the frequency domain with little loss of time localization. Numerical results demonstrate the superresolving capability and fast tracking rate, as well as the stability in the presence of additive noise. This technique provides a real-time method of tracking the instantaneous frequency of a signal. The tracking capability of a frequency modulated (FM) signal is compared to that given by the analytic signal and the Wigner distribution methods. The method is proposed for tracking multiple narrowband signals and has applications in tracking of frequency-hopping signals, dynamic subband analysis, demodulation of digital FM, and multiple target tracking