Patent ID: 8934365
Filing Date: 2015-01-13
Classification: H04B,H04L

Abstract:
1. A user equipment, adapted to an Orthogonal Frequency Division Multiplex (OFDM) wireless communication system comprising a base station, the user equipment comprising: a receiver that receives from at least one antenna a plurality of signals over a set of OFDM symbols transmitted by the base station through a propagation channel, the OFDM symbols comprising a plurality of resource elements distributed in time and frequency, the resource elements comprising a plurality of control messages; a channel estimation module that generates a channel power value and a channel noise power value from the resource elements that are distributed essentially across an entire frequency bandwidth; a demodulator retrieving at least one of the control messages; and a radio link monitoring module, comprising: a signal to noise ratio (SNR) calculation unit that calculates a SNR at the output of the demodulator according to the channel and noise power values, wherein the SNR allows assessing of the quality of the control message which is from the base station, wherein the radio link monitoring module further generates an unbiased channel power by removing a channel estimation error bias from the channel power, wherein an unbiased normalized channel power is obtained by scaling the unbiased channel power value by the noise power value, wherein the radio link monitoring module calculates the channel estimation error bias by scaling the channel noise power value with a factor dependent on a noise rejection in the channel estimation of the resource elements associated with the channel power value and channel noise power value, wherein the channel power and the channel noise power values are calculated separately for the antenna and the channel power and the channel noise power values are combined to generate a SNR value at the output of the demodulator, and wherein the unbiased normalized channel power is represented as: where P