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Physical Layer Built-In Security Analysis and Enhancement Algorithms for CDMA Systems

Abstract

Historically developed for secure communication and military use, CDMA has been identified as a major modulation and multiple-access technique for 3G systems and beyond. In addition to the wide bandwidth and low power-spectrum density which make CDMA signals robust to narrowband jamming and easy to be concealed within the noise floor, the physical layer built-in information privacy of CDMA system is provided by pseudorandom scrambling. In this paper, first, security weakness of the operational and proposed CDMA airlink interfaces is analyzed. Second, based on the advanced encryption standard (AES), we propose to enhance the physical layer built-in security of CDMA systems through secure scrambling. Performance analysis demonstrates that while providing significantly improved information privacy, CDMA systems with secure scrambling have comparable computational complexity and overall system performance with that of conventionally scrambled systems. Moreover, it is shown that by scrambling the training sequence and the message sequence separately with two independent scrambling sequences, both information privacy and system performance can be further improved. The proposed scheme can readily be applied to 3G systems and beyond.

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References

  1. Nichols R, Lekkas P: Wireless Security: Models, Threats, and Solutions, McGraw-Hill Telecom Professional Series. McGraw-Hill, New York, NY, USA; 2002.

    Google Scholar 

  2. IEEE : IEEE Standard for Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications. 1999.

    Google Scholar 

  3. Massey J: Shift-register synthesis and BCH decoding. IEEE Transactions on Information Theory 1969,15(1):122-127. 10.1109/TIT.1969.1054260

    Article  MathSciNet  MATH  Google Scholar 

  4. Bhashyam S, Aazhang B: Multiuser channel estimation and tracking for long-code CDMA systems. IEEE Transactions on Communications 2002,50(7):1081-1090. 10.1109/TCOMM.2002.800808

    Article  Google Scholar 

  5. Escudero CJ, Mitra U, Slock DTM: A Toeplitz displacement method for blind multipath estimation for long code DS/CDMA signals. IEEE Transactions on Signal Processing 2001,49(3):654-655. 10.1109/78.905897

    Article  Google Scholar 

  6. Weiss AJ, Friedlander B: Channel estimation for DS-CDMA downlink with aperiodic spreading codes. IEEE Transactions on Communications 1999,47(10):1561-1569. 10.1109/26.795824

    Article  Google Scholar 

  7. National Bureau of Standards : FIPS Publication 197: Advanced Encryption Standard (AES). 2001.http://csrc.nist.gov/publications/fips/fips197/fips-197.pdf

    Google Scholar 

  8. TIA/EIA/IS-95-B : Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spread Spectrum Cellular System. 1998.

  9. Garg VK: IS-95 CDMA and cdma 2000: Cellular/PCS Systems Implementation. Pearson Education, Upper Saddle River, NJ, USA; 1999.

    Google Scholar 

  10. National Bureau of Standards : FIPS Publication 81: DES Modes of Operation. 1980.http://www.itl.nist.gov/fipspubs/fip81.htm

    Google Scholar 

  11. Electronic Frontier Foundation (EFF) : EFF DES Cracker Project. http://www.eff.org/Privacy/Crypto/Crypto_misc/DESCracker/

  12. Parkvall S: Variability of user performance in cellular DS-CDMA-long versus short spreading sequences. IEEE Transactions on Communications 2000,48(7):1178-1187. 10.1109/26.855525

    Article  Google Scholar 

  13. Rappaport TS: Wireless Communications: Principles and Practices. 2nd edition. Prentice-Hall, Upper Saddle River, NJ, USA; 2002.

    Google Scholar 

  14. Proakis J: Digital Communications. 4th edition. McGraw-Hill, New York, NY, USA; 2000.

    Google Scholar 

Download references

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Correspondence to Tongtong Li.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License (https://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Li, T., Ling, Q. & Ren, J. Physical Layer Built-In Security Analysis and Enhancement Algorithms for CDMA Systems. J Wireless Com Network 2007, 083589 (2007). https://doi.org/10.1155/2007/83589

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  • DOI: https://doi.org/10.1155/2007/83589

Keywords

  • System Performance
  • Computational Complexity
  • Information Privacy
  • Physical Layer
  • Security Analysis