Design of equalizers for frequency selective MIMO systems with low redundancy



  • Ta Chi Hieu (Corresponding Author) Faculty of Radio-Electronics Engineering, Le Quy Don Technical University



MIMO; IBI; Frequency selective; Broadband; Decision-feedback equalizer.


In this paper, we propose several designs of filter bank based decision feedback equalizers (DFE) for frequency selective multi-input multi-output (MIMO) systems. Transmission schemes over frequency selective channels are typically block based, and redundancy in form of guard intervals must be used to avoid inter-block interference (IBI). This paper will focus on the case where spectral efficiency demands low levels of redundancy. Then the remaining IBI will be eliminated by a separate feedback loop. The co-channel interference (CCI) inherited in MIMO channels will be eliminated by different DFE schemes. In another approach, a multi-tap MIMO DFE will be designed to deal with both IBI and CCI. The simulation results show that for quasi-static frequency selective MIMO channels, the multi-tap DFE provides the best performance while for Raleigh frequency selective MIMO channels, the dual loop DFE is a good solution for transmission with low redundancy. 


[1]. A. J. Paulraj, D. A. Gore, R. U. Nabar and H. Bolcskei, "An overview of MIMO communications - a key to gigabit wireless," Proceedings of the IEEE, Vol. 92, No. 2 (2004), pp. 198-218, (2004). DOI:

[2]. A. Farhang, N. Marchetti, F. Figueiredo and J. P. Miranda, "Massive MIMO and waveform design for 5th generation wireless communication systems," Proc. of 1st International Conference on 5G for Ubiquitous Connectivity, Akaslompolo, Finland, pp. 70-75, (2014). DOI:

[3]. Zhendao Wang and G. B. Giannakis, "Wireless multicarrier communications," IEEE Signal Processing Magazine, Vol. 17, No. 3, pp. 29-48, (2000). DOI:

[4]. N. Al-Dhahir, "FIR channel-shortening equalizers for MIMO ISI channels," IEEE Transactions on Communications, Vol. 49, No. 2, pp. 213-218, (2001). DOI:

[5]. C. Toker, S. Lambotharan and J. A. Chambers, "Joint Transceiver Design for MIMO Channel Shortening," IEEE Transactions on Signal Processing, Vol. 55, No. 7, pp. 3851-3866, (2007). DOI:

[6]. F. Rusek and A. Prlja, "Optimal Channel Shortening for MIMO and ISI Channels," IEEE Transactions on Wireless Communications, Vol. 11, No. 2, pp. 810-818, (2012). DOI:

[7]. Li Youming, "Maximum shortening SNR design for MIMO channels," Proc. Of IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, Beijing, China, pp. 1488-1491, (2005).

[8]. M. Joham, D. A. Schmidt, J. Brehmer and W. Utschick, "Finite-Length MMSE Tomlinson–Harashima Precoding for Frequency Selective Vector Channels," IEEE Transactions on Signal Processing, Vol. 55, No. 6, pp. 3073-3088, (2007). DOI:

[9]. A. Stamoulis, G. B. Giannakis and A. Scaglione, "Block FIR decision-feedback equalizers for filterbank precoded transmissions with blind channel estimation capabilities," IEEE Transactions on Communications, Vol. 49, No. 1, pp. 69-83, (2001). DOI:

[10]. K. Kusume, M. Joham and W. Utschick, "MMSE block decision-feedback equalizer for spatial multiplexing with reduced complexity," Proc. of IEEE Global Telecommunications Conference, 2004. GLOBECOM '04., Dallas, TX, USA, pp. 2540-2544 Vol.4, (2004).

[11]. H. Sampath, P. Stoica and A. Paulraj, "Generalized linear precoder and decoder design for MIMO channels using the weighted MMSE criterion," IEEE Transactions on Communications, Vol. 49, No. 12, pp. 2198-2206, (2001). DOI:




How to Cite

Ta, C. H. “Design of Equalizers for Frequency Selective MIMO Systems With Low Redundancy”. Journal of Military Science and Technology, vol. 91, no. 91, Nov. 2023, pp. 20-27, doi:10.54939/1859-1043.j.mst.91.2023.20-27.



Research Articles