This paper outlines the operational concepts of recently proposed Interleaved Division Multiple Access (IDMA) scheme. Some interesting features of Interleaved Division Multiple Access (IDMA) over conventional Code Division Multiple Access (CDMA) are explained including its performance, simple receiver structure as well as spectral efficiency. The basic principle of IDMA is that interleaver is different for each user whereas CDMA employs different signatures. IDMA inherits many advantages of CDMA such as robust against fading, easy cell planning and dynamic channel sharing. Further IDMA increase the spectral efficiency and reduce the receiver complexity.

1. P. Li, L. Liu, K. Wu and W. K. Leung, “Interleave Division Multiple Access,” IEEE Transactions on Wireless Communication, Vol. 5, No. 4, 2006, pp. 938-945.
2. 2. L. Liu, J. Tong, and Li Ping, “Analysis and optimization of CDMA systems with chip-level interleavers,” IEEE J. Select. Areas Commun., vol. 24, no. 1, pp. 141–150, Jan. 2006.
3. Q. Huang, K. T. Ko, P. Wang, Li Ping, and S. Chan, “Interleave division multiple-access based broadband wireless networks,” in Proc. IEEE Information Theory Workshop, Chengdu, China, Oct. 22-26, 2006.
4. S. Brück, U. Sorger, S. Gligorevic, and N. Stolte,“Interleaving for outer convolutional codes in DSCDMA Systems,” IEEE Trans. Commun., vol. 48, pp. 1100–1107, July 2000
5. L. Ping, L. Liu, K. Wu, and W. Leung, “On interleave-division multiple-access,” in IEEE International Conference on Communications, vol. 5, 20-24 June 2004, pp. 2869–2873
6. Li Ping, “Interleave-division multiple access and chip-by-chip iterative multi-user detection,” IEEE Commun. Mag., vol. 43, no. 6, pp. S19–S23, Jun. 2005.
7. X. Wang and H. V. Poor, “Iterative (turbo) soft interference cancellation and decoding for coded CDMA,” IEEE Trans. Commun., vol. 47, pp. 1046– 1061, July 1999.
8. R. Mahadevappa and J. Proakis, “Mitigating multiple access interference and intersymbol interferece in uncoded CDMA systems with chip-level interleaving,” IEEE Trans. on Wireless Commun., vol. 1, no. 4, pp. 781–792, Oct. 2002.
9. Li Ping, L. Liu, K. Y. Wu, and W. K. Leung, “A unified approach to multi-user detection and spacetime coding with low complexity and nearly optimal performance,” in Proc. 40th Allerton Conference, Allerton House, USA, Oct. 2002, pp. 170–179. (www.ee.cityu.edu.hk/~liping/research)
10. L. Liu, W. K. Leung, and Li Ping, “Simple chip-by-chip multi-user detection for CDMA systems,” in Proc. IEEE VTC, Korea, Apr. 2003.
11. Li Ping, W. K. Leung, and K. Y. Wu, “Low-rate turbo-Hadamard codes,” submitted for publication, available: www.ee.cityu.edu.hk /~liping/research.
12. H. Zhu, B. Boroujeny, and C. Schlegel, “Pilot embedding for joint channel estimation and data detection in MIMO communication systems,” IEEE Commun. Lett., vol. 7, pp. 30–32, Jan. 2003.
13. K. S. Gilhousen, I. M. Jacobs, R. Padovani, A. J. Viterbi, L. A. Weaver, and C. E. Wheatly, “On the capacity of a cellular CDMA system,” IEEE Trans. Vehicular Technology, vol. 40, pp.303–312, May 1991.
14. E. Fishler and H. V. Poor, “On the tradeoff between two types of processing gain,” in Proc. 40th Allerton Conference, Allerton House, USA, Oct. 2002, pp. 1178–1187.
15. Shobha Rekh , Dr.S.Subha rani ,Dr.A.Shanmugam 2005 “Optimal choice of interleaver for turbo codes” acadjournal
16. C. Berrou, A. Glavieux, and P. Thitimajshaima, “Near Shannon limit error-correcting coding and decoding: turbo-codes,” in Proc. IEEE Int. Conf. Commun., May 1993, pp. 1064–1070.
17. Lance C. Perez, Jan Seghers and Daniel.J.Costello,” A distance spectrum interpretation of Turbo codes,” IEEE Trans. Inform. Theory, Special issue on Coding and Complexity April. 1996
18. C. Berrou, A. Glavieux and P. Thitimajshima, “Near Shannon Limit Error-Correcting Coding and Decoding: Turbo Codes”, International Conference on Communications, Geneva, Switzerland, pp. 1064-1070,May 1993.
19. J. Hokfelt, O.Edfors and T. Maseng, “A Turbo Code Interleaver DesignCriterion Based on the Performance of Iterative Decoding”, IEEE Communications Letters, Vol. 5, No. 2, February 2001.
20. S. Dolinar and D. Divsalar, “Weight Distributions for Turbo Codes Using Random and Nonrandom Permutations”, TDA Progress Report 42-122, JPL, August 1995.

IDMA CDMA Interleaver Spectral efficiency