Performance Analysis Of Channel Estimation Algorithms For A Mimo Ofdm System Under Digital Tv Channels

In 2005 the Brazilian government supported researches in order to design a new DTV standard which would employ the most recent technologies. One of the proposals for the new standard's physical layer was named Innovative Modulation for the Brazilian Digital TV System (MI-SBTVD). This proposal employs OFDM and has an operation mode where space-time diversity at the transmitter may be employed, requiring at the receiver side a channel estimation algorithm capable of identifying the MIMO channel. This paper presents some algorithms where the estimation at pilot subcarriers is obtained through a linear combination of two received symbols, and interpolation is done to provide channel gains at data carriers. As the proposed system has the pilot subcarriers positioned in such manner to allow bi-dimensional interpolation, four possible algorithms are evaluated through computer simulations. The results for digital TV channel models are compared. © 2006 IEEE.441445(2001) Digital Video Broadcasting (DVB)Framing structure, channel coding and modulation for digital terrestrial television, 300 (744), pp. V1.4.1. , European Broadcasting Union, ETSI ENInternational Telecommunication Union, Channel Coding, Frame Structure and Modulation Scheme for Terrestrial Integrated Services Digital Broadcasting (ISDB-T), ITU-R 205/11, 1999Welling, K., Rice, M., Coded Orthogonal Frequency Division Multiplexing for the Multipath Fading Channel (1999) Proceedings of the International Telemetering Conference, , Las Vegas, NV, OctoberAlamouti, S., A simple transmit diversity technique for wireless communications (1998) IEEE J. Select. Areas Communi, 16 (8), pp. 1451-1458Lindskog, E., Paulraj, A., A Transmit Diversity Scheme for Channels with Intersymbol Interference (2000) Proceedings of IEEE International Conference on Communications (ICC), pp. 307-311. , New OrleansLee, K.F., Willians, D.B., A Space-Time Coded Transmit Diversity Technique for Frequency Selective Fading Channels (2000) IEEE Sensor Array and Multichannel Signal Processing Workshop, pp. 149-152. , Cambridge, MA, MarchG. C. Lima and L. L. Mendes, Performance of STC-OFDM and SFC-OFDM for Digital Television Broadcasting, GSPx'06, Amsterdam, NL, 2006Benedetto, S., Biglieri, E., (1999) Principles of Digital Transmission: With Wireless Applications, p. 232. , Plenum Pub Corp, pagYacoub, M.D., (1993) Foundations of Mobile Radio Engineering, , CRC PressRinne, J., Renfors, M., Pilot Spacing in Orthogonal Frequency Division Multiplexing Systems on Practical Channels (1996) IEEE Transactions on Consumer Electronics, 42 (4), pp. 959-962. , PagesHoeher, P., Kaiser, S., Robertson, P., Two-Dimensional Pilot-Symbol-Aided Channel Estimation by Wiener Filtering (1997) Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing, 3, pp. 1845-1848(2000) Digital Television Systems Brazilian Tests Final Report, , http://www.set.com.br/artigos/testing.pdf, ABERT/SET, May, available i