Patent ID: 6519559
Filing Date: 2003-02-11
Classification: G10L

Abstract:
An apparatus comprising:a signal processing unit having an output port and operable for selectively routing an unfiltered input signal and a noise reduced version of the unfiltered input signal to the output port in response to a signal derived from a noise power estimate, wherein the input signal has an average noise power and the signal derived from the noise power estimate is derived from a comparison of a noise floor threshold, which is the average noise power, to the noise power estimate, wherein the noise floor threshold (NFI) is calculated as follows: NFT=1N&it;&Sum;i=0M&it;MAX&it;(Fi&it;(0),â€¦&it;â€ƒ,Fi&it;(M-1)),wherein N is a number of time frames over which an estimate is averaged, M is a number of bins in each time slice, and F(M) is a noise floor power estimate for bin M.