In Chapter 4, we have find out the theoretical LCR and AFD of mobile-to-mobile Rician fading channel. Another contribution is that we derived the probability dis-tribution of the slope of the fading envelope, which is obtained from the ACF of the mobile-to-mobile Rician fading channel in chapter 3. In the last part, we validate the LCR and AFD from simulations. We also observer the influence of the LOS component and terminal mobility on the channel fading.
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7.3 Capacity Analysis of MIMO Mobile-to-Mobile Rician Fading Channels
In Chapter 5, we have developed a sum-of-sinusoids simulation method for the MIMO in a mobile-to-mobile fading channel. Based on the “correlated double ring” scattering model [14], we incorporate the effect of Doppler effects, antenna separation and LOS components for the MIMO system in a mobile-to-mobile environment. We have also derived the capacity upper bound of the mobile-to-mobile MIMO Rician channel. The channel capacity has been validated through simulations. We find that for MIMO systems with constant numbers of scatterers, increasing number of antennas cannot linearly increase the capacity. The capacity per antenna is decreased more as Rician factor increases. We also find that the total channel capacity is related to the richness of the scattering environment.
7.4 Higher Order Statistics of Mobile-to-Mobile MIMO Rician Channels
In Chapter 6, we have investigated the temporal behavior of the capacity of the mobile-to-mobile MIMO Rician channel. Besides, we proposed a “semi-analytical”
model for computing the LCR and AFD of the MIMO channel capacity. From those simulation results, we observed the influence of the LOS component, doppler fre-quency and other parameters on the temporal behavior of the MIMO channel capac-ity.
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7.5 Suggestion for Future Work
For the future research of the thesis, we provide the following suggestions to extend our works:
• Find out tighter bounds for the MIMO channel capacity.
• Derive the exact correlation functions of the MIMO channel capacity.
• Derive the exact form of LCR and AFD for the MIMO channel capacity.
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Bibliography
[1] P. Dent, G. E. Bottomley, and T. Croft, “Jakes fading model revisited,” Elec-tronics Letters, vol. 29, pp. 1162–1163, June 1993.
[2] W. C. Jakes, Microwave Mobile Communications. Piscataway, NJ: Wiley-IEEE Press, 1994.
[3] M. F. Pop and N. C. Beaulieu, “Limitations of sum-of-sinusoids fading channel simulator,” IEEE Transactions on Communications, vol. 49, pp. 699–708, April 2001.
[4] C. Xiao, Y.R.Zheng, and N. Beaulie, “Second-order statistical properties of the WSS Jakes fading simulator,” IEEE Transactions on Communications, vol. 50, pp. 888–891, June 2002.
[5] A. S. Akki and F. Haber, “A statistical model for mobile-to-mobile land com-munication channel,” IEEE Transactions on Vehicular Technology, vol. VT-35, Feb 1986.
[6] R. Wang and D. Cox, “Channel modeling for ad hoc mobile wireless networks,”
IEEE Vehicular Technology Conference, vol. 1, pp. 21–25, May 2002.
[7] C. S. Patel, G. L. St¨uber, and T. G. Pratt, “Simulation of Rayleigh faded mobile-to-mobile communication channels,” IEEE Vehicular Technology Con-ference, vol. 1, pp. 163–167, October 2003.
[8] D. J. Young and N. C. Beaulieu, “The generation of correlated Rayleigh random variates by inverse discrete Fourier transform,” IEEE Transactions on Commu-nications, vol. 48, pp. 1114–1127, July 2000.
[9] J.-Z. Sun, J. Sauvola, and D. Howie, “Features in future: 4G visions from a tech-nical perspective,” Proceedings of IEEE Global Telecommunications Conference , vol. 6, pp. 25–29, Nov 2001.
[10] IEEE TGn Sync working group. [Online]. Available:
http://www.tgnsync.org/techdocs/
[11] P. Beckman, S. Verma, and R. Rao, “Use of mobile mesh networks for inter-vehicular communication,” IEEE Vehicular Technology Conference, vol. 4, pp.
2712–2715, Oct 2003.
[12] S. Haykin, “Cognitive radio: brain-empowered wireless communications,” IEEE Journal on Selected Areas in Communications, vol. 23, pp. 201–220, Feb 2005.
[13] H. Kang, G. L. St¨uber, T. G. Pratt, and M. A. Ingram, “Studies on the capacity of MIMO systems in mobile-to-mobile environment,” IEEE Wireless Commu-nications and Networking Conference, vol. 1, pp. 21–25, March 2004.
[14] L.-C. Wang and Y.-H. Cheng, “A statistical mobile-to-mobile Rician fading chan-nel model,” in IEEE Vehicular Technology Conference, May 2005.
[15] V. Erceg, L. Greenstein, S. Y. Tjandra, S. R. Parkoff, A. Gupta, B. Kulic, A. A. Julius, and R. Bianchi, “Theory, experiment, and statistical models,”
IEEE Journal on Selected Areas in Communications, vol. 7, pp. 1205–1211, Jul 1999.
[16] Y. R. Zheng and C. Xiao, “Improved models for the generation of multiple un-correlated Rayleigh fading waveforms,” IEEE Communications Letter, vol. 6, pp. 256–258, June 2002.
[17] C. Xiao and Y. Zheng, “A statistical simulation model for mobile radio fading channels,” IEEE Wireless Communications and Networking Conference, vol. 1, pp. 144–149, March 2003.
[18] A. Giorgetti, M. Chiani, M. Shafi, and P. J. Smith, “Level crossing rates and MIMO capacity fades: impacts of spatial/temporal channel correlation,” IEEE International Conference on Communications, vol. 5, pp. 3046–3050, May 2003.
[19] P.-H. Kuo and P. J. Smith, “Temporal behavior of MIMO channel quality met-rics,” IEEE Wireless Communications and Networking Conference, June 2005.
[20] T. S. Rappaport, Wireless Communication: Principles and Practice, 2nd ed.
New York: Prentice Hall, 1996.
[21] J. I. Smith, “A computer generated multipath fading simuation for mobile radio,”
IEEE Transactions on Vehicular Technology, vol. 24, pp. 39–40, August 1975.
[22] A. S. Akki, “Statistical properties of mobile-to-mobile land communication chan-nels,” IEEE Transactions on Vehicular Technology, vol. 43, pp. 826–831, Nov 1994.
[23] A. Papoulis, Probability, Random Variables, and Stochastic Process, 3rd ed.
McGraw-Hill.
68
[24] S. O. Rice, “Statistical properties of sine wave plus random noise,” Bell System Technical Journal, pp. 109–157, January 1948.
[25] G. L. St¨uber, Principles of Mobile Communication, 2nd ed. Kluwer Academic.
[26] D. Halliday and R. Resnick, Fundamentals of Physics, 3rd ed. John Wiley&Sons.
[27] D. Tse and P. Viswanath, Fundamentals of Wireless Communication. Draft, to be polished by Cambridge University Press, 2004.
[28] A. Paulraj, R. Narbar, and D. Gore, Introduction to Space-Time Wireless Com-munications. Cambridge University Press, 2003.
[29] G. J. Foschini and M. J. Gans, “On limits of wireless communications in a fading environment when using multiple antennas,” Wireless Personal Commu-nications, no. 6, pp. 311–335, 1998.
[30] I. E. Teletar, “Capacity of multi-antenna Gaussian channels,” AT &T Bell Lab.
Tech. Memo., June 1995.
[31] P. J. Smith and M. Shafi, “On a Gaussian approximation to the capacity of wireless MIMO systems,” IEEE International Conference on Communications, vol. 1, pp. 406–410, April 2002.
[32] M. Shafi and P. J. Smith, “An approximate capacity distribution for MIMO systems,” IEEE Transactions on Communications, vol. 52, pp. 887–890, June 2004.
[33] C. Gao, M. Zhao, S. Zhou, and Y. Yao, “Capacity autocorrelation characteristic of MIMO systems over doppler spread channels,” IEEE Vehicular Technology Conference, vol. 1, pp. 44–46, April 2003.
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Vita
Yun-Huai Cheng
He was born in Taiwan, R. O. C. in 1981. He received a B.S. in Electrical and Control Engineering from National Chiao-Tung University in 2003. From July 2003 to June 2005, he worked his Master degree in the Wirelsss Internet System Engineer-ing Lab in the Department of Communication EngineerEngineer-ing at National Chiao-Tung University. His research interests are in the field of wireless communications.
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