A near real-time signal to interference ratio measurement technique in a frequency-selective multipath fading channel for the WCDMA system

This paper presents a new concept of realtime SIR estimation for CDMA systems. Unlike conventional symbol-based SIR estimator according to the successively received symbols, we propose a new chip-based SIR estimation method. The key contribution of this paper is to propose a mechanism to exploit the spreading codes of CDMA signals to estimate SIR. Under the COST 259 W-CDMA channel model, the simulation results demonstrate that the proposed chip-based SIR estimation algorithm can accurately measure SIR in less than 10^-4 second in several chips, which is about over 1,000 times faster than the traditional symbol-based SIR estimation algorithms