In this paper the authors analyze the effect of signal pre-correlation filtering in the ldquoBOC-Gated-PRNrdquo (ldquoBOC-GPRNrdquo) discriminator technique, recently proposed for use within Global Navigation Satellite System receivers to handle the new signal modulation scheme). The proposed discriminator is introduced to eliminate the tracking ambiguity for Delay Locked Loops and strengthen multipath resistance for precise GNSS applications. In practice, a pre-correlation filter with insufficient bandwidth can, in general, increase the error due to multipath and noise. However, it is preferred that the bandwidth of the front end filter is kept as narrow as possible for other limitation. Hence focusing on the multipath error and discriminator gain optimization of the DLL, the tracking performance with the BOC-GPRN discriminator is investigated by adjusting the parameters of the proposed discriminator and the pre-correlation filter (e.g. the double-sided bandwidth and transition bandwidth). The relationship among those parameters is discussed.