A client device for a wireless network, configured to: - receive a signal that contains at least one reference symbol modulated onto a plurality of sub carriers, - determine a plurality of weights based on the reference symbol and line-of-sight channel frequency responses for the subcarriers, wherein each of said plurality of weights is associated with one of said subcarriers and wherein the plurality of weights are calculated from estimated subcarrier specific frequency responses of the channel through which the signal was received; - determine a gain associated with said received signal using said plurality of weights, wherein the gain is indicative of the strength of the received signal; - determine said gain as a real part of a weighted sum of complex vectors, each of said complex vectors representing a corresponding part of said received signal on a corresponding one of said plurality of subcarriers, wherein the plurality of weights is used to produce said weighted sum and the gain is determined using the formula: r ^ = Re ∑ y f * w f wherein r̂ is the estimated beam-specific gain of a received signal, y f ∗ is a complex conjugate of the f th received subcarrier, w f is a weight applied to the f th received subcarrier, and w = [ w 1 , w 2 , ... , w f ] is a vector of all weights applied to the 1 st to f th received subcarriers, - transmit information indicative of said determined gain to a network node of said wireless network; - use said determined gain in said client device to determine a location of the client device; and - determine a reliability of said determined gain, and - transmit said information indicative of said determined gain to said network node only if said determined reliability is better than a predetermined threshold. - receive a signal that contains at least one reference symbol modulated onto a plurality of sub carriers, - determine a plurality of weights based on the reference symbol and line-of-sight channel frequency responses for the subcarriers, wherein each of said plurality of weights is associated with one of said subcarriers and wherein the plurality of weights are calculated from estimated subcarrier specific frequency responses of the channel through which the signal was received; - determine a gain associated with said received signal using said plurality of weights, wherein the gain is indicative of the strength of the received signal; - determine said gain as a real part of a weighted sum of complex vectors, each of said complex vectors representing a corresponding part of said received signal on a corresponding one of said plurality of subcarriers, wherein the plurality of weights is used to produce said weighted sum and the gain is determined using the formula: r ^ = Re ∑ y f * w f wherein r̂ is the estimated beam-specific gain of a received signal, y f ∗ is a complex conjugate of the f th received subcarrier, w f is a weight applied to the f th received subcarrier, and w = [ w 1 , w 2 , ... , w f ] is a vector of all weights applied to the 1 st to f th received subcarriers, - transmit information indicative of said determined gain to a network node of said wireless network; - use said determined gain in said client device to determine a location of the client device; and - determine a reliability of said determined gain, and - transmit said information indicative of said determined gain to said network node only if said determined reliability is better than a predetermined threshold. <EOS>