Skip to main content

Advertisement

Log in

Estimation of Channel State Information (CSI) in Cell-Free Massive MIMO Based on Time of Arrival (ToA)

  • Published:
Wireless Personal Communications Aims and scope Submit manuscript

Abstract

Cell-free massive multiple input multiple output (MIMO) comprises a large number of distributed single antenna access points (APs) connected to a network controller through backhaul. Each user is served by neighbouring APs simultaneously. Cell-free Massive MIMO provides decent throughput and coverage improvement as compared to a small-cell. Yet, channel state information (CSI) estimation is still a bottleneck in massive MIMO systems. In this paper, we propose an estimation method that does not need channel statistics or any historical assumption. We use the received pilots at the APs to provide CSI with mitigated co-pilot interference. The received signal is used to estimate the time of arrival (TOA) of signals from different paths, and, subsequently, signals that travel long distances are filtered out. The results show noticeable enhancement over LS estimation if the estimate of TOA is accurate.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2

Similar content being viewed by others

References

  1. Marzetta, T. L. (2010). Noncooperative cellular wireless with unlimited numbers of base station antennas. IEEE Transactions on Wireless Communications, 9(11), 3590–3600.

    Article  Google Scholar 

  2. Rusek, F., et al. (2013). Scaling up MIMO: Opportunities and challenges with very large arrays. IEEE Signal Processing Magazine, 30(1), 40–60.

    Article  Google Scholar 

  3. Hoydis J., Ten Brink S., & Debbah M. (2011). Massive MIMO: How many antennas do we need? In 2011 49th annual Allerton conference on communication, control, and computing (Allerton) (pp. 545–550).

  4. Liu, Z., & Dai, L. (2014). A comparative study of downlink MIMO cellular networks with co-located and distributed base-station antennas. IEEE Transactions on Wireless Communications, 13(11), 6259–6274.

    Article  Google Scholar 

  5. Truong K.T., & Heath R.W. (2013). The viability of distributed antennas for massive MIMO systems. In 2013 Asilomar conference on signals, systems and computers, Pacific Grove, CA, 2013, pp. 1318–1323.

  6. Buzzi, S., & D’Andrea, C. (2017). Cell-free massive MIMO: User-centric approach. IEEE Wireless Communications letters, 6(6), 706–709.

    Article  Google Scholar 

  7. Ngo, H. Q., Ashikhmin, A., Yang, H., Larsson, E. G., & Marzetta, T. L. (2016). Cell-free massive MIMO versus small cells. IEEE Transactions on Wireless Communications, 16(3), 1834–1850.

    Article  Google Scholar 

  8. Chen, Z., & Bjornson, E. (2018). Channel hardening and favorable propagation in cell-free massive MIMO with stochastic geometry. IEEE Transactions on Communications, PP(c), 1.

    Google Scholar 

  9. Almamori A., & Mohan S. (2017). A spectrally efficient algorithm for massive MIMO for mitigating pilot contamination. In 2017 IEEE 38th Sarnoff Symposium (pp. 1–5) Newark.

  10. Ugurlu, U., Wichman, R., Ribeiro, C. B., & Wijting, C. (2016). A multipath extraction-based CSI acquisition method for FDD cellular networks with massive antenna arrays. IEEE Transactions on Wireless Communications, 15(4), 2940–2953.

    Article  Google Scholar 

  11. Chen, J. T., Paulraj, A., & Reddy, U. (1999). Multichannel maximum-likelihood sequence estimation (MLSE) equalizer for GSM using a parametric channel model. IEEE Transactions on Communications, 47(1), 53–63.

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Aqiel Almamori.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Almamori, A., Mohan, S. Estimation of Channel State Information (CSI) in Cell-Free Massive MIMO Based on Time of Arrival (ToA). Wireless Pers Commun 114, 1825–1831 (2020). https://doi.org/10.1007/s11277-020-07450-8

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11277-020-07450-8

Keywords

Navigation