Time-of-arrival estimation for E-OTD location in GERAN

Abstract

In this paper, the problem of time-of-arrival (TOA) estimation for E-OTD location in a GSM/EDGE Radio Access Network (GERAN) is described. To increase the number of available bursts for TOA estimation (and therefore increase the accuracy), the mobile can use bursts from all time slots. However, this requires that the TOA estimation algorithm is able to handle GMSK and 8PSK bursts without a-priori knowledge about the modulation scheme. In this paper, the mutual effect of different modulation formats on the TOA estimation performance for E-OTD location is investigated. A TOA estimation algorithm is described, which does not require a blind detection of the modulation scheme.