Primitive Polynomials for Iterative Recursive Soft Sequential Acquisition of Concatenated Sequences

Abstract

An iterative initial sequence acquisition technique is proposed for the pseudo-noise signal derived from a pair of m-sequences used for generating the concatenated sequence, which relies on the soft-in-soft-out detection to improve the acquisition performance. This recursive soft sequential estimation technique has a linearly increasing complexity with the number of chips in the concatenated sequence. Receiving as few as S consecutive chips of a (2S - 1)-chip sequence is sufficient for the local concatenated-sequence generator of the receiver to synchronize. Hence, this initial synchronization technique is eminently suitable for long m-sequences and concatenated sequences. Another key result is the comparison of m-sequences and concatenated sequences regarding the acquisition time. It is also observed that low-order primitive polynomials (PPs) achieve better performances than higher-order polynomials for both the m-sequences and concatenated sequences. When considering PPs having a higher number of taps, the exploitation of concatenated sequences is capable of achieving in excess of 3-dB signal-to-noise ratio gains over m-sequences.

Keywords

• Recursive soft sequential estimation (RSSE)
• EXIT chart
• acquisition time (AT)
• m-sequence%22%2C%22default_operator%22%3A%22AND%22%7D%7D%7D"> <italic xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">m</italic>-sequence
• concatenated sequence
• pseudo-noise (PN)