In the code delay lock loop of GNSS receiver, the false-lock problem of binary offset carrier signal was caused by its multi-peak characteristic for the present multipath mitigation technique. An optimal discriminator curve design technique was proposed by using the least squares method combined with the truncated singular value decomposition. As a result, the local code correlation reference waveforms which have no ambiguity points in tracking the BOC signals can be derived. The simulation results show that the proposed method can realize coherent and non-coherent binary offset carrier signal discriminators without false lock points. Generally, there is a performance degradation in the tracking jitter. However, there are performance promotions for the BOC(1,1) signal, which has a 8.184 MHz front-bandwidth, with 61.8% increase in the multipath error envelope area, and 4 to 5 dB increase in the tracking precision compared with W2 waveform. Thus, the selection of waveform parameters involves a trade-off between the tracking ambiguity and tracking performances obtained under multipath and thermal noise conditions.