Differential Post Detection Integration Techniques for Robust Code Acquisition

• Published in: IEEE transactions on communications Vol. 55; no. 11; pp. 2172 - 2184
• Main Authors: Villanti, M., Salmi, P., Corazza, G.E.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.11.2007; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acquisitions; Analytical models; Applied sciences; Code acquisition; Detectors; differential techniques; Error analysis; Exact sciences and technology; frequency error; Frequency synchronization; Gain; Information, signal and communications theory; Land mobile radio cellular systems; Marketing; Mathematical analysis; Miscellaneous; Navigation; Offsets; Optimization; Performance gain; post detection integration (PDI); Robustness; Signal processing; Simulation; Spread spectrum communication; spread-spectrum systems; Telecommunications and information theory; Testing; Uncertainty; Performance evaluation; Differential detection; differential techniques; post detection integration (PDI); Optimization; Simulation; Code acquisition; spread-spectrum systems; Non coherent detection; Signal processing; Spread spectrum; Frequency offset; Differential method; Differential technique; frequency error
• ISSN: 0090-6778; 1558-0857
• DOI: 10.1109/TCOMM.2007.908535

In this paper, the problem of code acquisition for spread-spectrum systems is investigated in the presence of frequency errors. The classic approach of noncoherent post detection integration (NCPDI) is contrasted with differential post detection integration (DPDI), presented in two different versions, namely DPDI-Real and DPDI-Abs, respectively, suited for fine and large frequency offsets. The differential schemes are characterized thoroughly introducing a novel analytical treatment that is validated by simulations. In order to fairly quantify the potential gains introduced by the differential solutions, specific detector parameter optimization is performed for each scheme. The interesting result is that the DPDI significantly outperforms the classic NCPDI approach for large frequency errors, and behaves close to it for small offsets. DPDI can, thus, be considered as a very robust PDI solution with moderate complexity.