Patent ID: 8045927

Claim:
A method, comprising: receiving, in a radio receiver, a first signal through a radio channel, the first signal including a desired signal transmitted from a transmitter; transforming the received first signal from a time domain into a frequency domain; selecting specific one or more frequency components of the transformed first signal, wherein the specific one or more frequency components are known to carry the desired signal the radio receiver is attempting to detect, thereby obtaining a frequency domain representation of a signal located at the selected one or more frequency components; correlating the frequency domain representation of the signal located at the selected one or more frequency components with a reference signal representing the desired signal the radio receiver is attempting to detect, thereby producing a correlation value describing similarity between the signal located at the selected one or more frequency components and the reference signal; estimating a reception power value for the signal located at the selected one or more frequency components; calculating a decision metric from the correlation value and the reception power value; and determining, on the basis of the decision metric, whether the signal located at the selected one or more frequency components is the desired signal or noise.