New LFSR based methodology to generate PRN codes with lengths suitable for GNSS having low correlation

With the advent of CDMA based satellite navigation; the requirement and importance of PRN codes have increased and have become inevitable in daily life. Satellite navigation systems require PRN codes of different lengths which often call for truncation or padding. Generation of good PRN codes with period not similar to 2
ⁿ
-1 is still an open challenge. This paper presents an LFSR based PRN code generation which is independent of the PRN code period. For comparison the state-of-the-art BeiDou B1I PRN codes are used with period 2046 (2
¹¹
-2). It is observed that the sequence generated from the new method are found to have better correlation, in particular 2.5-3 dB improvement in auto-correlation and 1.5-2.5 dB improvement in cross-correlation as compared to state-of-the-art BeiDou B1I codes. The method proposed allows generating large set of sequences based on the correlation and balance requirement which is independent of the PRN code period and hence suitable for GNSS systems.