Recursive Noise Floor Estimation in WCDMA

Online estimation of the noise floor is essential for the accurate scheduling of wideband code-division multiple-access (WCDMA) enhanced uplink (EUL) channel transmissions. The noise floor is used for computation of the load of the uplink of the cell, which is then used to compute the momentary headroom available for EUL traffic. This paper proves a result on Kalman filter scaling, which significantly extends the dynamic range of a previous noise-floor-estimation scheme. This paper proceeds by proving that an optimal Bayesian minimum estimator can be written in recursive form using geometric-rather than arithmetic-averaging. As compared with previous algorithms, the recursive scheme reduces the memory requirement without compromising performance, at the same time that the tracking properties are enhanced.