Phase-based frequency estimation using filter banks

An apparatus for estimating the frequency of complex sinusoidal signals in the presence of noise, comprising:

• means for filtering and decimating a received input signal through a multichannel filter bank, said filter bank having a plurality of channels and one or more stages;
• means for applying outputs of said filter bank as inputs to a detector, each said output being a channel, said detector determining which of said outputs contains said sinusoidal signals and selecting one or more of said outputs, each said selected output corresponding to a respective one of said sinusoidal signals;
• means for computing phase differences for one or more said selected outputs;
• and
• means for estimating frequencies for said respective sinusoidal signals from said phase differences.

A program storage device readable by a machine, tangibly embodying a program of instructions executable by said machine to perform method steps for estimating the frequency of complex sinusoidal signals in the presence of noise, said method steps comprising:

• filtering and decimating a received input signal through a multichannel filter bank, said filter bank having a plurality of channels and one or more stages;
• applying outputs of said filter bank as inputs to a detector, each said output being a channel, said detector determining which of said outputs contains said sinusoidal signals and selecting one or more of said outputs, each said selected output corresponding to a respective one of said sinusoidal signals;
• computing phase differences for one or more said selected outputs;
• and
• estimating frequencies for said respective sinusoidal signals from said phase differences.