Evaluation of GPS Dual Frequency Application Using L2 Civilian Signal

Abstract

The L2 Civilian (L2C) signal transmitted by the GPS Block IIR-M satellite is the first of the new generation of signals available for public users. The second and third satellites (SVN52/PRN31 and SVN58/PRN12) were launched successfully in 2006. This work focuses on development of a GPS L2C software receiver and on evaluation of ionospheric delay estimation using observations from L1C/A and L2C tracking. We developed a software GPS receiver to measure L1C/A and L2C observations, and compared ionospheric delay of the developed receiver and conventional receiver. Several tests were conducted to evaluate performance of the L2C signal using actual data. Two advantages of the L2C signal were confirmed through the tests. First, the C=N 0 for the L2C code is higher than that of the L2P(Y). The L2C signal can be used for vertical and horizontal measurement along with L1C/A as dual-frequency application becomes available over wider area and for longer each day. Second, is that the direct tracking for the L2C signal allows the ionopheric delay to be estimated as accurately as the proprietary tracking for L2P(Y).