Article ID: 2018XBL0082
We have previously proposed synchronized spread spectrum code division multiple access (SS-CDMA) as a method for short message communication using the Quasi-Zenith Satellite System (QZSS). In this paper, we have evaluated the time synchronization accuracy due to the sky view factor experimentally. The absolute time error to achieve a 100 % cumulative probability density function (CDF) was evaluated to 26.5 ns when using an elevation mask of 30°. This means that it is possible to achieve 98 % of the accommodation rate in the proposed synchronized SS-CDMA under the condition of a sky view factor of over 44 %. The main cause of absolute time error is considered to be deterioration of the position dilution of precision (PDOP).