Skip to main content Accessibility help
  • Get access
    Check if you have access via personal or institutional login
  • Cited by 2
  • Print publication year: 2016
  • Online publication date: June 2016

9 - Coordinated multi-point transmission in 5G



The performance of a wireless network strongly depends on the user positions in a cell. More precisely, the UEs (User Equipments) at the cell border typically experience much lower throughput than those nearer to the transmitting Base Station (BS). This is mainly due to the presence of inter-cell interference, generated by concurrent transmissions in other cells. Inter-cell interference is particularly relevant for modern wireless communication systems like Universal Mobile Telecommunications System (UMTS) or Long-Term Evolution (LTE), and also 5G, where the frequency reuse factor is one or very close to one. In such scenario the system is primarily interference limited, and the performance cannot be improved by simply increasing the transmitted power. Hence, techniques are necessary in order to (1) target inter-cell interference and (2) reduce the gap between the cell edge and average throughput. Consequently, these alternative techniques allow a more even user experience throughout the whole network.

In principle, the following techniques can be pursued to tackle inter-cell interference:

• Interference can simply be treated as white noise. This is clearly suboptimal, as it ignores properties of the interfering signals that could be exploited in order to improve signal reception quality.

• Interference can be avoided through statically leaving some transmit resources in some cells muted (e.g. fractional frequency reuse), or otherwise constraining the usage of resources, or through coordinated scheduling among cells, as investigated in Chapter 11.

• The impact of interference can be alleviated at the receiver side through e.g. Interference Rejection Combining (IRC), where multiple receive antennas and subsequent receive filters are used to attenuate the interference to a certain extent.

• Interference may be decoded and cancelled, a technique that is for instance studied in 3GPP in the context of Network-Assisted Interference Cancelation (NAIC).

• At the transmitter side, interference can also be partially avoided by performing interference-aware precoding, i.e. applying precoding such that the interference caused toward adjacent cells is reduced.

• Ultimately, signals from other cells can in fact be treated as a useful signal energy instead of interference, if (in the downlink) multiple nodes jointly transmit signals that coherently overlap at the intended receiver, and destructively overlap at interfered receivers. In the uplink (UL), multiple nodes can jointly receive and decode the signals from multiple UEs, and in this form also exploit interference rather than seeing it as a burden.

[1] Marsch, P. and Fettweis, G., Coordinated Multi-Point in Wireless Communications: From Theory to Practice. Cambridge, UK: Cambridge University Press, 2011.
[2] Hanly, S. V. and Whiting, P. A., “Information-theoretic capacity of multi-receiver networks,” Telecommunication Systems, vol. 1, no. 1, pp. 1–42, March 1993.
[3] Shamai, S. and Zaidel, B., “Enhancing the cellular downlink capacity via co-processing at the transmitting end,” in IEEE Vehicular Technology Conference, pp. 1745–1749, Rhodes, Greece, May 2001.
[4] Karakayali, M. K., Foschini, G. J. and Valenzuela, R. A.. “Network coordination for spectrally efficient communications in cellular systems,” IEEE Wireless Communications, vol. 13, no. 4, pp.56–61, August 2006.
[5] 3GPP TR 36.819, “Coordination Multi-Point Operation for LTE Physical Layer Aspects (Release 11),” Technical Report TR 36.819 V1.0.0, Technical Specification Group Radio Access Network, June 2011.
[6] 3GPP TR 36.814, “E-UTRA: Further advancements for E-UTRA physical layer aspects (Release 9),” Technical Report TR 36.814 V9.0.0, Technical Specification Group Radio Access Network, March 2010.
[7] Cadambe, V. R. and Jafar, S. A., “Interference alignment and degrees of freedom of the K-user interference channel,” IEEE Transactions on Information Theory, vol. 54, no.8, pp. 3425–3441, August 2008.
[8] ICT-247223 ARTIST4G project, “Interference Avoidance techniques and system design,” Deliverable D1.4, July 2012.
[9] ICT-317669 METIS project, “Final performance results and consolidated view on the most promising multi-node/multi-antenna transmission technologies,” Deliverable D3.3, February 2015,
[10] Osseiran, A., Monserrat, J., and Mohr, W., Mobile and Wireless Communications for IMT-Advanced and Beyond. Chichester: Wiley, 2011.
[11] Gresset, N., Halbauer, H., Zirwas, W., and Khanfir, H., “Interference avoidance techniques for improving ubiquitous user experience,” IEEE Vehicular Technology Magazine, vol. 7, no. 4, pp. 37–45, December 2012.
[12] Kotzsch, V. and Fettweis, G., “On synchronization requirements and performance limitations for CoMP systems in large cells,” in IEEE International Workshop on Multi-Carrier Systems & Solutions, Herrsching, pp. 1–5, May 2011.
[13] Wirth, V. T., Schellmann, M., Haustein, T., and Zirwas, W., “Synchronization of cooperative base stations,” in IEEE International Symposium on Wireless Communication Systems, Reykjavik, October 2008, pp. 329–334,.
[14] Manolakis, K., Oberli, C., and Jungnickel, V., “Synchronization requirements for ofdm-based cellular networks with coordinated base stations: Preliminary results,” in International OFDM Workshop, Hamburg, Germany, September 2010.
[15] Phan-Huy, D. T., Sternad, M., and Svensson, T., “Adaptive large MISO downlink with Predictor Antennas Array for very fast moving vehicles,” in International Conference on Connected Vehicles & Expo, Las Vegas, USA, December 2013, pp. 331–336.
[16] Foschini, G., Karakayali, K., and Valenzuela, R., “Coordinating multiple antenna cellular networks to achieve enormous spectral efficiency,” IEE Proceedings-Communications, vol. 153, no. 4, pp. 548–555, August 2006.
[17] Rahul, H. S., Kumar, S., and Katabi, D., “JMB: Scaling wireless capacity with user demands,” in ACM conference on Applications, technologies, architectures, and protocols for computer communication, Helsinki, August 2012, pp. 235–246.
[18] Zirwas, W. and Haardt, M., “Channel prediction for B4G radio systems,” in IEEE Vehicular Technology Conference, Dresden, June 2013, pp. 1–5.
[19] Thiele, L., Kurras, M., Olbrich, M., and Matthiesen, B., “Channel aging effects in CoMP transmission: Gains from linear channel prediction,” in IEEE Annual Asilomar Conference on Signals, Systems and Computers, Monterey, November 2011.
[20] Thiele, L., Kurras, M., Olbrich, M., and Börner, K., “On feedback requirements for CoMP joint transmission in the quasi-static user regime,” in IEEE Vehicular Technology Conference, Dresden, June 2013.
[21] Boccardi, F. and Huang, H., “A near-optimum technique using linear precoding for the MIMO broadcast channel,” in IEEE International Conference on Acoustics, Speech and Signal Processin, Honolulu, April 2007.
[22] Apelfröjd, R., Sternad, M., and Aronsson, D., “Measurement-based evaluation of robust linear precoding for downlink CoMP,” in IEEE International Conference on Communications, Ottawa, Canada, June 2012.
[23] Thiele, L., “Spatial interference management for OFDM-based cellular networks,” PhD thesis, TUM 2013.
[24] Thiele, L., Kurras, M., Borner, K., and Haustein, T., “User-aided sub-clustering for CoMP transmission: Feedback overhead vs. data rate trade-off,” in Asilomar Conference on Signals, Systems and Computers, Pacific Grove, November 2012, pp. 1142–1146.
[25] Jungnickel, V., Manolakis, K., Zirwas, W., Panzner, B., Braun, V., Lossow, M., Sternad, M., Apelfröjd, R., and Svensson, T., “The role of small cells, coordinated multi-point and massive MIMO in 5G,” IEEE Communications Magazine, vol. 52, no. 5, pp. 44–51, May 2014.
[26] ICT-317669 METIS project, “First performance results for multi-node/multi-antenna transmission technologies,” Deliverable D3.2, April 2014,
[27] Marsch, P. and Fettweis, G., “Static clustering for cooperative multi-point (CoMP) in mobile communications,” in IEEE International Conference on Communications, Kyoto, June 2011, pp. 1–6.
[28] Zirwas, W., Mennerich, W., and Khan, A., “Main enablers for advanced interference mitigation,” European Transactions on Telecomunications, vol. 24, no. 1, January 2013.
[29] Jungnickel, V., Jaeckel, S., Jaeckel, S., Thiele, L., Krueger, U., and Helmolt, A. C. von, “Capacity measurements in a multicell MIMO system,” in IEEE Global Communications Conference, San Francisco, November 2006.
[30] Thiele, L., Wirth, T., Haustein, T., Jungnickel, V., Schulz, E., and Zirwas, W., “A unified feedback scheme for distributed interference management in cellular systems: Benefits and challenges for real-time tmplementation,” in European Signal Processing Conference, Glasgow, August 2009.
[31] Zirwas, W., “Opportunistic CoMP for 5G massive MIMO multilayer networks,” in ITG Workshop on Smart Antennas, Ilmenau, March 2015, pp. 1–7.
[32] Gesbert, D., Hanly, S., Huang, H., Shitz, S. Shamai, Simeone, O., and Yu, W., “Multi-cell MIMO cooperative networks: a new look at interference,” IEEE Journal on Selected Areas in Communications, vol. 28, no. 9, pp. 1380–1408, December 2010.
[33] Bjornson, E., Zakhour, R., Gesbert, D., and Ottersten, B., “Cooperative multicell precoding: Rate region characterization and distributed strategies with instantaneous and statistical CSI,” IEEE Transactions on Signal Processing, vol. 58, no. 8, pp. 4298–4310, August 2010.
[34] Lähetkangas, E., Pajukoski, K., Vihriälä, J., et al., “Achieving low latency and energy consumption by 5G TDD mode optimization,” in IEEE International Conference on Communications, Sydney, June 2014, pp. 1–6.
[35] Komulainen, P., Tolli, A. and Juntti, M.. “Effective CSI signaling and decentralized beam coordination in TDD multi-cell MIMO systems,” IEEE Trans. Signal Processing, vol. 61, no. 9, pp.2204–2218, May 2013.
[36] Jayasinghe, P., Tölli, A., Kaleva, J., and Latva-aho, M., “Bi-directional signaling for dynamic TDD with decentralized beamforming,” in IEEE International Conference on Communications, London, June 2015.
[37] Bamby, M. S. El, Bennis, M., Saad, W., and Latva-aho, M., “Dynamic uplink-downlink optimization in TDD-based small cell networks,” in IEEE International Symposium on Wireless Communication Systems, Barcelona, August 2014, pp. 939–944.
[38] Sohn, I., Lee, K. B., and Choi, Y., “Comparison of decentralized timeslot allocation strategies for asymmetric traffic in TDD systems,” IEEE Trans. Wireless Commun., vol. 8, no. 6, pp. 2990–3003, June 2009.
[39] ICT-317669 METIS project, “Components of a new air interface: Building blocks and performance,” Deliverable D2.3, April 2014,
[40] Komulainen, P., Tolli, A., and Juntti, M., “Effective CSI signaling and decentralized beam coordination in TDD multi-cell MIMO systems,” IEEE Trans. on Signal Processing, vol. 61, no. 9, pp. 2204–2218, May 2013.
[41] Shi, C., Berry, R. A., and Honig, M. L., “Bi-directional training for adaptive beamforming and power control in interference networks,” IEEE Trans. on Signal Processing, vol. 62, no. 3, pp. 607–618, February 2014.
[42] Shi, Q., Razaviyayn, M., Luo, Z. Q., and He, C., “An iteratively weighted MMSE approach to distributed sum-utility maximization for a MIMO interfering broadcast channel,” IEEE Trans. on Signal Processing, vol. 59, no. 9, pp. 4331–4340, September 2011.
[43] Cadambe, V. and Jafar, S., “Interference alignment and spatial degrees of freedom for the k user interference channel,” in IEEE International Conference on Communications, Beijing, May 2008, pp. 971–975.
[44] ICT-317669 METIS project, “Initial report on horizontal topics, first results and 5G system concept,” Deliverable D6.2, March 2014,
[45] Aziz, D. and Weber, A., “Transmit precoding based on outdated interference alignment for two users multi cell MIMO system,” in IEEE International Conference on Computing, Networking and Communications, San Diego, January 2013, pp. 708–713.
[46] Sadek, M., Tarighat, A., and Sayed, A., “A leakage-based precoding scheme for downlink multi-user mimo channels,” IEEE Trans. on Wireless Communications, vol. 6, no. 5, pp. 1711–1721, May 2007.
[47] Boccardi, F., Heath, R. W. Jr., Lozano, A., Marzetta, T. L., and Popovski, P., “Five disruptive technology directions for 5G,” IEEE Commun. Mag., vol. 52, no. 2, pp. 74–80, February 2014.
[48] Fodor, G., Dahlman, E., Mildh, G., Parkvall, S., Reider, N., Miklós, G., and Turányi, Z., “Design aspects of network assisted device-to-device communications,” IEEE Commun. Mag., vol. 50, no. 3, pp.170–177, March 2012.
[49] Ji, M., Tulino, A. M., Llorca, J., and Caire, G., “On the average performance of caching and coded multicasting with random demands,” in IEEE International Symposium on Wireless Communications Systems, Barcelona, August 2014, pp. 922–926.
[50] Boccardi, F., Clercks, B., Ghosh, A., Hardouin, E., Kusume, K., Onggosanusi, E., and Tang, Y., “Multiple-antenna techniques in LTE-advanced,” IEEE Commun. Mag., vol. 50, no. 3, pp. 114–121, March 2012.
[51] Hwang, I., Chae, C. B., Lee, J., and Heath, R. W., “Multicell cooperative systems with multiple receive antennas,” IEEE Wireless Commun. Mag., vol. 20, no. 1, pp. 50–58, February 2013.
[52] Baracca, P., Boccardi, F., and Benvenuto, N., “A dynamic clustering algorithm for downlink CoMP systems with multiple antenna UEs,” EURASIP Journal on Wireless Commun. and Networking, 2014, vol. 125, August 2014.
[53] 3GPP TR 36.866, “Network-assisted interference cancellation and suppression for LTE (Release 12),” Technical Report TR 36.866 V1.1.0, Technical Specification Group Radio Access Network, November 2013.