Performance of network-based mobile location techniques within the 3GPP UTRA TDD standards

As part of the ongoing 3GPP standardisation activities for third generation mobile systems, the need to meet the FCC E911 Phase II regulations was anticipated and system features were designed accordingly. This paper describes the features that were incorporated into the UTRA TDD standards (both the 3.84 MHz and 1.28 MHz variants) to this end. Whilst the solutions adopted for user equipment (UE) positioning for the FDD and TDD systems are broadly the same, differences within the design and operation of the air interfaces has meant that there are some differences in the way these solutions have been implemented. These differences are described.