Detección de señales codificadas con correlación generalizada cruzada en UWB-LPS

The use of Ultra -WideBand (UWB) techniques is considered an attractive solution for indoor Local Positioning Systems (LPS). In this case, the positioning is usually performed by hyperbolic trilateration techniques measuring the time difference of arrival (TDOA) between the received signals coming from the beacons placed in the environment. The detection of the true arrival instant for the used encoded signals is important in the accuracy of the system. The most widely used technique consist of performing the correlation between the received signal and the sequence to be detected. For that, matched filters are used and then, the instant at which appears the maximum of the correlation function is detected. In this paper the use of Generalized Cross Correlation (GCC) is presented. This allows the components around the carrier frequency to be enhanced, improving the detection of the maximum correlation peak and hence the accuracy of measurement of difference distances.