METHOD AND NETWORK NODE FOR FFT BASED POWER DETECTION FOR LBT IN LTE LAA

A method performed in a radio access node includes the radio access node receiving a data for transmission to a second radio access node over a communication channel having an unlicensed spectrum. The method further includes, in response to receiving the data, the radio access node receiving a channel measurement signal over the communication channel. The method further includes the radio access node performing an N-point Fast Fourier Transform (FFT) on the channel measurement signal to produce a frequency domain signal with N bins. The method further includes the radio access node performing a power measurement on the frequency domain signal. The method further includes the radio access node analyzing the power measurement of the frequency domain signal. The method further includes the radio access node transmitting the data based on the analysis of the power measurement.