OBF Radiation Behavior of Smart Antenna The Fourth Generation LTE Network on inter-city Express Railway

Subject Areas : Majlesi Journal of Telecommunication Devices

Amin  Aliabadi ¹ (Sama technical and vocatial training college,Islamic Azad University,Malayer)
Amin  Heydari ² (Islamic azad University of Boushehr)

Received: 2013-03-09 Accepted : 2013-03-09 Published : 2012-03-01

Keywords: en,

Abstract :

communication systems of high-speed railway have inherent disadvantages and advantages. The estimation error of direction-of-arrival (DOA) of desired users caused by channel feedback delay and high moving speed make the common beamforming technique of smart antennas work abnormally. Instead, the opportunistic beamforming (OBF) with dumb antennas which does not need channel feedback is proper for high-speed railway. As the system has linear topology, regular movement as well as predictable location and speed information, the OBF can be improved to adapt to this scenario. In this article, conventional OBF is first introduced to the communication systems of high-speed railway. By multiplying random complex on each transmit antenna, the channel fluctuation dynamic range is extended so that multiuser diversity can be exploited. And then location information is employed to assist the conventional one. Communication systems in high-speed railway have the advantage of predictable location and speed information. The improved OBF can perform closer to the performance of coherent beamforming. Numerical analysis and simulation results show that both two algorithms can improve the system performance significantly.

References:

[1] A. Paulraj, R. Nabar, and D. Gore, “Introduction to Space-TimeWirelessCommunications”. Cambridge, UK: CambridgeUniversity Press, 2003.

[2] Meng Cheng ;Xuming Fang, “Location information-assisted opportunistic beamforming in LTE system for high-speed railway,” EURASIP Journal on Wireless Communications and Networking 2012, 2012:210 doi:10.1186/1687-1499-2012-210, Published: 3 July 2012

[3] A.Aliabadi, “LTE And LTE-Advance Version 9 of the 3GPP for High Bit Rate Data Transmission For 4Generation of Mobile Networks,” Majlesi Journal of Telecommunication Devices, ISSN: 2322-1550,Vol. 1, No. 2, June 2012.

[4] Aliabadi, Design ,Optimization and power control of Cellular Mobile communication (HSDPA,HSUPA,HSPA+ and LTE) , Iranian Scientific Publishers of Javdan Kherad, Tehran (2012), ISBN 9789646030749,Feb 2012.)

[5] GP White, YV Zakharov, Data communications to trains from high-altitude platforms. IEEE Trans. Veh. Technol 56(4), 2253–2266 (2007).

[6] LC Godara, Application of antenna arrays to mobile communications—Part II: beamforming and direction-of-arrival considerations. Proc. IEEE 85(8), 1195–1245 (1997). Publisher Full Text .

[7] L. C. Andrews, R. L. Phillips, and C. Y. Hopen, “Laser Beam Scintillation with Applications”, SPIE Optical Engineering Press,Bellingham, Washington, 2001.

[8] ITU-R Guidelines for evaluation of radio interface technologies for IMT-Advanced (http://www, 2011), . itu.int/dms_pub/itu-r/opb/rep/R-REP-M.2135-1-2009-PDF-E.pdf webcite.

[9] L. C. Andrews and R. L. Phillips, “Laser Beam Propagationthrough Random Media” ,SPIE Optical Engineering Press, 1998.

[10] G Gaire, S Shamai, On the achievable throughput of a multiantenna Gaussian broadcast channel. IEEE Trans. Inf. Theory 49(7), 1691–1706 (2003). Publisher Full Text.

[11] DNC Tse, P Viswanath, Fundamentals of Wireless Communications (Cambridge University Press, Cambridge, 2005).