Department of Communications and Networking

School of Electrical Engineering

Aalto University

The current research interests of the communication theory group are in cognitive, heterogeneous and self-organizing wireless networks, as well as coding theory and multiantenna techniques. The development of cellular systems keeps opening up new frontiers and enabling the use of methods of increasing sophistication to optimize system performance on all layers in Radio Access Networks (RANs).

Current topics include- 5G wireless networks: D2D, spectrum and interference management, large scale MIMO, network optimization
- Distributed & self-organizing management of large scale RANs
- Network-level interference cancelation and coordination
- Coding on compact manifolds

- Joonas Pääkkönen (together with Camilla Hollanti), defended 2018, now at Aalto
- Sergio Lembo, defended 2017, now at Helsinki University.
- Furqan Ahmed , defended 2016, now in industry.
- Udesh Oruthota, defended 2016, now at Sri Lanka Technological Campus.
- Athul Prasad , defended 2015, now in industy .
- Renaud-Alexandre Pitaval, defended 2014, now in industy .
- Lu Wei, defended 2013, now at University of Michigan-Dearborn.
- Helka-Liina Määttänen, defended 2012, now in industy .
- Chia-Hao Yu, defended 2012, now in industy .

Department of Communications and Networking, Electrical Engineering
Building, Otakaari 5, 02150 Espoo, Finland

Directions via Google Maps

Department of Communications and Networking, PO box 13000, FI-00076 Aalto University, Finland

Email: firstname dot lastname at aalto dot fi

Some recent journal papers:

- R.-A. Pitaval, L. Wei, O. Tirkkonen and C. Hollanti,
**Density of Spherically-Embedded Stiefel and Grassmann Codes**,*IEEE Transactions on Information Theory*, in press. - F. Ahmed, A. Dowhuszko and O. Tirkkonen,
**Self-organizing Algorithms for Interference Coordination in Small Cell Networks**,*IEEE Transactions on Vehicular Technology*, vol. 66, no. 9, pp. 8333--8346, Sept 2017. - N. Ermolova and O. Tirkkonen,
**Interference Analysis in Wireless Networks Operating over Arbitrary Fading Channelswith Heterogeneous Poisson Fields of Transmitters**,*IEEE Signal Processing Letters*, vol. 24, no. 9, pp. 1388-1392, July 2017. - J. Deng, O. Tirkkonen, R. Freij-Hollanti, T. Chen and N.
Nikaein,
**Resource Allocation and Interference Management for Opportunistic Relaying in Integrated mmWave/sub-6GHz 5G Networks**,*IEEE Communications Magazine*, vol. 55, no. 6, pp. 94-101, June 2017. - L. Wei, R.-A. Pitaval, J. Corander and O. Tirkkonen,
**From Random Matrix Theory to Coding Theory: Volume of a Metric Ball in Unitary Group**,*IEEE Transactions on Information Theory*, vol. 63, no. 5, pp. 2814--2821, May 2017. - J. Xu, X. Yan, Y. Zhu, J. Wang, Y. Yang,
X. Ge, G. Mao and O. Tirkkonen,
**Statistical Analysis of Path Losses for Sectorized Wireless Netwoks**,*IEEE Transactions on Communications*, vol. 65, no. 4, pp. 1828-1838, April 2017. - Y. Beyene, R. Jäntti, O. Tirkkonen, K. Ruttik, S. Iraji, A.
Larmo, T. Tirronen and J. Torsner,
**NB-IoT Technology Overview and Experience from Cloud-RAN Implementation**,*IEEE Wireless Communications*, vol. 24, no. 3, pp. 26-32, March 2017. - R.-A. Pitaval, L. Wei, O. Tirkkonen and J. Corander,
**Volume of metric balls in high-dimensional complex Grassmann manifolds**,*IEEE Transactions on Information Theory,*vol. 62, no. 9, pp. 5105-5116, Sept. 2016. - J. Liu, G. Wu, S. Li and O. Tirkkonen,
**On Fixed-point Implementation of Log-MPA for SCMA Signals**,*IEEE Wireless Communications Letters*, vol. 5, no. 3, pp. 324-327, June 2016. - M. Bhatnagar, R. Mallik and O. Tirkkonen,
**Performance Evaluation of Best-Path Selection in a Multihop Decode-and-Forward Cooperative System**,*IEEE Transactions on Vehicular Technology*, vol. 65, no. 4, pp. 2722-2728, April 2016. - N. Ermolova and O. Tirkkonen,
**Using beta distributions for modeling distances in random finite networks**,*IEEE Communications Letters*, vol. 20, no. 2, pp. 308-311, Feb 2016. - U. Oruthota, F. Ahmed, O. Tirkkonen,
**Ultra-Reliable Link Adaptation for Downlink MISO Transmission in 5G Cellular Networks**,*Information*, vol. 7, no.1, pp. 1--18, March 2016. - F. Ahmed and O. Tirkkonen,
**Simulated Annealing Variants for Self-organized Resource Allocation in Small Cell Networks**,*Applied Soft Computing*, vol. 38, pp. 762-770, Jan 2016. - R.-A. Pitaval, O. Tirkkonen, R. Wichman, K. Pajukoski, E. Lähetkangas, E. Tiirola,
**Full-duplex Self-backhauling for Small-cell 5G Networks**,*IEEE Wireless Communications,*vol. 22, no. 5, pp. 83-89, Oct 2015. - R.-A. Pitaval, W. Dai and O. Tirkkonen,
**Convergence of Gradient Descent for Low-Rank Matrix Approximation**,*IEEE Transactions on Information Theory,*vol. 61, no. 8, pp. 4451-4458, Aug. 2015. - B. Singh, S. Hailu, K. Koufos, A. A. Dowhuszko, O. Tirkkonen, R. Jäntti and R. Berry,
**Coordination protocol for inter-operator spectrum sharing in co-primary 5G small cell networks**,*IEEE Communications Magazine,*vol. 53, no. 7, pp. 34-40, July 2015. - U. Oruthota and O. Tirkkonen,
**Link Adaptation of Precoded MIMO-OFDMA System with I/Q Interference**,*IEEE Transactions on Communications,*vol. 63, no. 3, pp. 780-790, March 2015. - N. Ermolova and Olav Tirkkonen,
**Cumulative Distribution Function of Bivariate Gamma Distribution with Arbitrary Parameters, and Applications,***IEEE Communications Letters*, vol. 19, no. 2, pp. 167-170, Feb 2015. - T. Chen, H. Zhang, X. Chen and O. Tirkkonen,
**SoftMobile: Control Evolution for Future Heterogeneous Mobile Networks,***IEEE Wireless Communications*, vol. 21, no. 6, pp. 70-78, Dec 2014. - L. Wei, O. Tirkkonen and Y.-C. Liang,
**Multi-source Signal Detection with Arbitrary Noise Covariance,***IEEE Transactions on Signal Processing*, vol. 62, no. 22, pp. 5907-5918, Sept 2014. - N. Ermolova and O. Tirkkonen,
**Laplace Transform of Product of Generalized Marcum Q, Bessel I, and Power Functions with Applications,***IEEE Transactions on Signal Processing*, vol. 62, no. 11, pp. 2938-2944, May 2014. - N. Ermolova, Y. Zou, M. Valkama and Olav Tirkkonen,
**Error-rate Analysis of OFDM Radio Link over Mobile Rayleigh Channel under Multiple RF Impairments,***IEEE Transactions on Vehicular Technology*, vol. 63, no. 2, pp. 930-936, Feb 2014. - R.-A. Pitaval and O. Tirkkonen,
**Joint Grassmann-Stiefel Quantization for MIMO product codebooks,***IEEE Transactions on Wireless Communications*, vol. 13, no. 1, pp. 210-222, Jan. 2014. - N. Ermolova and O. Tirkkonen,
**Outage Probability Analysis in Fading Channels with Co-Channel Interference and Background Noise: eta-mu/eta-mu, eta-mu/kappa-mu, and kappa-mu/eta-mu scenarios,***IEEE Transactions on Wireless Communications*, vol. 13, no. 1, pp. 291-297, Jan. 2014. - L. Wei, Z. Zheng, O. Tirkkonen and J. Hämäläinen,
**On the Ergodic Mutual Information of Multiple Cluster Scattering MIMO Channels,***IEEE Communications Letters*, vol. 17, no. 9, pp. 1700 - 1703, Sept 2013. - N. Ermolova and Olav Tirkkonen,
**Link Performance Bounds of MIMO Transmit Beamforming Systems Operating over Generalized Fading Channels,***IEEE Communications Letters*, vol. 17, no. 9, pp. 1696 - 1699, Sept 2013. - L. Wei, P. Dharmawansa and O. Tirkkonen,
**Multiple Primary User Spectrum Sensing in the Low SNR Regime,***IEEE Transactions on Communications*, vol. 61, no. 5, pp. 1720-1731, May 2013. - A. Prasad, O. Tirkkonen, P. Lunden, O. Yilmaz, L. Dalsgaard and C. Wijting,
**Energy Efficient Inter-Frequency Small Cell Discovery Techniques for LTE-Advanced Heterogeneous Network Deployments,***IEEE Communications Magazine*, vol. 51, no. 5, pp. 72-81, May 2013. - M. R. Bhatnagar and O. Tirkkonen,
**PL Decoding in Double Differential Modulation Based Decode-and-Forward Cooperative System,***IEEE Communications Letters*, vol. 17, no 5, pp 860-863, May 2013. - Z. Zheng, L. Wei, J. Hämäläinen and O. Tirkkonen,
**A Blind Time-Reversal Detector in the Presence of Channel Correlation,***IEEE Signal Processing Letters*, vol. 20, no 5, pp. 459-462, May 2013. - Z. Zheng, L. Wei, J. Hämäläinen and O. Tirkkonen,
**Approximation to distribution of product of random variables using orthogonal polynomials for log-normal density,***IEEE Communications Letters*, vol. 16, pp. 2028-2031, Dec. 2012. - N. Ermolova and O. Tirkkonen,
**Outage probability over composite eta-mu fading--shadowing radio channels,***IET Communications*, vol.6, pp. 1898-1902, 2012. - U. Oruthota and O. Tirkkonen,
**SER/BER Expression for M-QAM OFDM Systems with Imperfect Channel Estimation and I/Q Imbalance,***EURASIP J. Wireless Communications and Networking*, Sept. 2012. - N. Ermolova and O. Tirkkonen,
**Distribution of Diagonal Elements of a General Central Complex Wishart Matrix,***IEEE Communications Letters*, vol. 16, no. 9, pp. 1373-1376, Sept. 2012. - L. Wei and O. Tirkkonen,
**Spectrum Sensing in the Presence of Multiple Primary Users,***IEEE Transactions on Communications*, vol. 60, no. 5, pp. 1268-1277, May 2012. - N. Ermolova and O. Tirkkonen,
**Multivariate eta-mu Distribution with Constant Correlation Model,***IEEE Communications Letters*, vol. 16, no. 4, pp. 454-457, April 2012. -
J.-M. Koljonen, M. Peltomäki, O. Tirkkonen, and M. Alava,
**Algorithms for Self-Organizing Resource Allocation in Wireless Networks,***IEEE Transactions on Vehicular Technology*, vol. 61, no. 1, pp. 346-359, Jan 2012. -
R.-A. Pitaval, H.-L. Määttänen, K. Schober, O. Tirkkonen and R. Wichman,
**Beamforming Codebooks for Two Transmit Antenna Systems based on Optimum Grassmannian Packings,***IEEE Transactions on Information Theory*, vol. 57, no. 10, pp. 6591 -6602, Oct 2011.

- O. Tirkkonen, C. Boyd and R. Vehkalahti,
**Grassmannian Codes from Multiple Families of Mutually Unbiased Bases**,*IEEE Internat. Conf. on Information Theory (ISIT)*, 5 pp., June 2017. - J. Liu, G. Wu, S. Li and O. Tirkkonen,
**Blind detection of uplink grant-free SCMA with unknown user sparsity**,*IEEE ICC*, 6 pp., May 2017. - O. Tirkkonen and C. Studer,
**Subset-codebook precoding for 1-bit massive multiuser MIMO**,*Conference on Information Sciences and Systems (CISS)*, 5 pp., March 2017. - J. Deng, A. Dowhuszko, R. Freij and O. Tirkkonen,
**Relay Selection and Resource Allocation for D2D-Relaying under Uplink Cellular Power Control**,*IEEE Globecom, Workshop on Emerging Technologies for 5G Wireless Cellular Networks*, 6 pp., Nov 2015. - A. Barreal, J. Pääkkönen, D. Karpuk, C. Hollanti and O.
Tirkkonen,
**A Low-Complexity Message Recovery Method for Compute-and-Forward Relaying**,*IEEE Information Theory Workshop*, 5 pp., Oct 2015. - R.-A. Pitaval, L. Wei, O. Tirkkonen and J. Corander,
**On the exact volume of metric balls in complex Grassmann manifolds**,*IEEE Information Theory Workshop*, 5 pp., Oct 2015. - B. Singh, K. Koufos, O. Tirkkonen and R. Jäntti,
**Repeated spectrum sharing games in multi-operator heterogeneous networks**,*IEEE DySPAN*, 8 pp., Oct 2015. - L. Zhou, J. Kerttula, N. Malm, Y. Beyene, K. Ruttik, O.
Tirkkonen and R. Jäntti,
**Creating Secondary Spectrum Usage Opportunity for D2D Communication with Interference Cancellation**,*IEEE DySPAN, Demonstration track*, 2 pp., Oct 2015. - Y. Beyene, N. Malm, J. Kerttula, L. Zhou, K. Ruttik, R. Jäntti,
O. Tirkkonen and C. Bockelmann,
**Spectrum Sharing for MTC Devices in LTE**,*IEEE DySPAN, Demonstration track*, 2 pp., Oct 2015. - J. Kerttula, Y. Beyene, N. Malm, L. Zhou, K. Ruttik, O.
Tirkkonen and R. Jäntti,
**Spectrum Sharing in D2D Enabled HetNet**,*IEEE DySPAN, Demonstration track*, 2 pp., Oct 2015. - J. Pääkkönen, C. Hollanti and O. Tirkkonen,
**Device-to-device data storage with regenerating codes**,*Internat. Workshop on Multiple Access Communications*, pp. 57-69, Sept 2015. - Y. Beyene, C. Boyd, K. Ruttik, C. Bockelmann, O. Tirkkonen and
R. Jäntti,
**Compressive Sensing for MTC in New LTE Uplink Multi-User Random Access Channel**,*IEEE Africon*, 5 pp. Sept 2015. - C. Boyd, R.-A. Pitaval, O. Tirkkonen and R. Wichman,
**On the Time-Frequency Localisation of 5G Candidate Waveforms**,*Signal Processing Advances for Wireless Communications (SPAWC)*, 5 pp., June 2015. - L. Wei, R.-A. Pitaval, J. Corander and O. Tirkkonen,
**On the Volume of a Metric Ball in Unitary Group**,*IEEE ISIT*, 7 pp., June 2015. - S. Lembo, A. Dowhuszko and O. Tirkkonen,
**Joint Resource Allocation in Mobile Networks with Macro Cellular and Device-to-Device Communication**,*IEEE ICC, Workshop on Device-to-Device Communication for Cellular and Wireless Networks*, 6 pp., June 2015. - B. Singh, K. Koufos, O. Tirkkonen and R. Berry,
**Co-primary inter-operator spectrum sharing over a limited spectrum pool using repeated games**,*IEEE ICC*, 6 pp., June 2015. - C. Boyd, R.-A. Pitaval, U. Parts and O. Tirkkonen,
**Non-binary Classical Error-correcting Codes for Quantum Communication**,*IEEE ICC*, 6 pp., June 2015. - F. Ahmed and O. Tirkkonen,
**Self-Organized Physical Cell ID Assignment in Multi-operator Heterogeneous Networks**,*IEEE VTC-Spring*, 5 pp., May 2015. - L. Zhou, K. Ruttik, O. Tirkkonen,
**Interference Canceling Power Optimization for Device-to-Device Communication**,*IEEE VTC-Spring*, 5 pp., May 2015. - U. Oruthota and O. Tirkkonen,
**I/Q Interference in Device-to-Device Underlay Communication with Uplink Power Control**,*IEEE VTC-Spring*, 5 pp., May 2015. - L. F. Del Carpio, A. Dowhuszko, O. Tirkkonen and G. Wu,
**Cooperative Device-to-Device Communication**,*IEEE VTC-Spring*, 6 pp., May 2015. - S. Hailu, P. Lunden, E. Virtej, N. Kolehmainen, O. Tirkkonen and
C. Wijting,
**DRX-Aware Power and Delay Optimized Scheduler for Bursty Traffic Transmission**,*IEEE VTC-Spring*, 5 pp., May 2015. - J. Vihriälä, E. Lähetkangas, K. Pajukoski, N. Ermolova and O.
Tirkkonen,
**On the Waveforms for 5G Mobile Broadband Communications**,*IEEE VTC-Spring*, 5 pp., May 2015. - L. Zhou, K. Ruttik, O. Tirkkonen, R. Berry,
**Cell-edge Inversion by Interference Cancellation for Downlink Cellular Systems,***IEEE Internat. Conf. on Communication Systems*, 5 pp., Nov. 2014. - S. Hailu, A. Dowhuszko, O. Tirkkonen and L. Wei,
**One-Shot Games for Spectrum Sharing among Co-Located Radio Access Networks,***IEEE Internat. Conf. on Communication Systems*, 6 pp., Nov. 2014. - B. Singh, K. Koufos and O. Tirkkonen,
**Co-primary inter-operator spectrum sharing using repeated games,***IEEE Internat. Conf. on Communication Systems*, 5 pp., Nov. 2014. - F. Ahmed and O. Tirkkonen,
**Topological Aspects of Greedy Self-Organization,***IEEE Internat. Conf. on Self-Adaptive and Self-Organizing Systems*, pp. 31--39, Sept 2014. - J. Kerttula, N. Malm, K. Ruttik, R. Jäntti and O. Tirkkonen,
**Implementing TD-LTE as software defined radio in general purpose processor***ACM SIGCOMM, workshop of Software Radio Implementation Forum*, 7 pp., August 2014. - B. Singh, K. Koufos and O. Tirkkonen,
**Coordination protocol for inter-operator spectrum sharing based on spectrum usage favors,***European Conf. on Networks and Communications (EuCNC)*, 2 pp., June 2014. - F. Ahmed, O. Tirkkonen, A. Dowhuszko and M. Juntti,
**Distributed Power Allocation in Cognitive Radio Networks under Network Power Constraint,***Internat. Conf. on Cognitive Radio Oriented Wireless Networks (CrownCom)*, 6 pp., June 2014. - S. Hailu, A. Dowhuszko and O. Tirkkonen,
**Adaptive Co-primary Shared Access Between Co-located Radio Access Networks,***Internat. Conf. on Cognitive Radio Oriented Wireless Networks (CrownCom)*, 5 pp., June 2014. - G. Berardinelli, F. Tavares, T. Sørensen, P. Mogensen, O. Tirkkonen and P. Amin,
**Distributed Initial Synchronization for 5G small cells,***IEEE VTC-Spring*, 6 pp., 2014. - G. Berardinelli, K. Pajukoski, E. Lähetkangas, R. Wichman, O. Tirkkonen, P. Mogensen,
**On the potential of OFDM enhancements as 5G waveforms,***IEEE VTC-Spring*, 6 pp., 2014. - J. Pääkkönen, C. Hollanti and O. Tirkkonen,
**Device-to-Device Data Storage for Mobile Cellular Systems,***IEEE GLOBECOM*, 6 pp., Dec 2013. - L.F. Del Carpio, M. Lampinen, M. Enescu, T. Koivisto, O. Tirkkonen,
**Network-assisted widely linear receivers for LTE,***IEEE VTC-Fall*, 5 pp., 2013. - R.-A. Pitaval and O. Tirkkonen,
**Flag Orbit Codes and Their Expansion to Stiefel Codes,***IEEE Information Theory Workshop*, 5 pp, Sept. 2013. - I. Harjula, R. Wichman, K. Pajukoski, E. Lähetkangas, E. Tiirola and O. Tirkkonen,
**Full Duplex Relaying for Local Area,***IEEE PIMRC*, pp. 2684--2688, Sept 2013. - A. Prasad, P. Lunden, O. Tirkkonen and C. Wijting,
**Mobility State Based Flexible Inter-Frequency Small Cell Discovery for Heterogeneous Networks,***IEEE PIMRC*, pp. 2057--2061, Sept 2013. - A. Prasad, P. Lunden and O. Tirkkonen,
**Enhanced Small Cell Discovery in Heterogeneous Networks Using Optimized RF Fingerprints,***IEEE PIMRC*, pp. 2973--2977, Sept 2013. - A. Dowhuszko, O. Tirkkonen, J. Karjalainen, T. Henttonen and J. Pirskanen,
**A Decentralized Cooperative Uplink/Downlink Adaptation Scheme for TDD Small Cell Networks,***IEEE PIMRC*, pp. 1682--1687, Sept 2013. - F. Ahmed, A. Dowhuszko, O. Tirkkonen and R. Berry,
**A Distributed Algorithm for Network Power Minimization in Multicarrier Systems,***IEEE PIMRC*, pp. 1914--1918, Sept 2013. - L. Wei and O. Tirkkonen,
**Multiple Primary User Spectrum Sensing for Unknown Noise Statistics,***IEEE PIMRC*, pp. 871--875, Sept 2013. - A. Dowhuszko, F. Ahmed and O. Tirkkonen,
**Decentralized Transmit Beamforming Scheme for Interference Coordination in Small Cell Networks,***IEEE BlackSeaCom*, pp. 121--126, July 2013. - L. Zhou, K. Ruttik, O. Tirkkonen and R. Berry,
**Interference canceling power control games in Gaussian interference channels,***IEEE ISIT*, pp. 1112--1116, July 2013. - Sergio Lembo, Petteri Lunden, Olav Tirkkonen and Kimmo Valkealahti,
**Optimal muting ratio for Enhanced Inter-Cell Interference Coordination (eICIC) in HetNets,***IEEE ICC, Workshop on small cell networks, pp. 1145--1149, June 2013.* - M. Ding, O. Tirkkonen, R. A. Berry and S. Ulukus,
**Distributed Precoding for MISO Interference Channels with Channel Mean Feedback: Algorithms and Analysis,***IEEE ICC*, pp. 5640-5645, June 2013. - O. Tirkkonen, E. Lähetkangas, K. Pajukoski, E. Tiirola, I. Harjula,
**Multihop Relaying for Local Area Access,***IEEE VTC--Spring Workshops*, 5 pp., June 2013. - P. Amin, O. Tirkkonen, T. Henttonen and E. Pernilä,
**Dynamic Frequency Selection based on Carrier Pricing between cells,***IEEE VTC--Spring*, 5 pp., June 2013. - N. Ermolova and O. Tirkkonen,
**Performance analysis of communication systems over generalized alpha-lambda-eta-mu fading radio channels,***IEEE VTC--Spring, 5 pp., June 2013.* - U. Oruthota, O. Tirkkonen and P. Dharmawansa,
**Analysis of Uplink Power Control in Cellular Mobile Systems,***IEEE VTC--Spring, 5 pp., June 2013.* - A. Prasad, P. Lunden, O. Tirkkonen and C. Wijting,
**Energy Efficient Small-Cell Discovery Using Received Signal Strength Based Radio Maps,***IEEE VTC--Spring*, 5 pp., June 2013. - A. Prasad, P. Lunden, O. Tirkkonen and C. Wijting,
**Energy-Efficient Flexible Inter-Frequency Scanning Mechanism for Enhanced Small Cell Discovery,***IEEE VTC--Spring*, 5 pp., June 2013. - R.-A. Pitaval, A. Srinivasan and O. Tirkkonen,
**Codebooks in Flag Manifolds for Limited Feedback MIMO Precoding,***ITG Conference on Systems, Communications and Coding (SCC)*, 5 pp., Jan. 2013. - C.H. Yu, B. Mumey and O. Tirkkonen,
**Distributed Multiple Relay Selection by an Auction Mechanism,***IEEE GLOBECOM*, pp. 4392--4397, Dec. 2012. - R.-A. Pitaval and O. Tirkkonen,
**Volume of Ball and Hamming-type Bounds for Stiefel Manifold with Euclidean Distance,***Asilomar Conference on Signals, Systems and Computers*, pp. 483-487, Nov. 2012. - R.-A. Pitaval and O. Tirkkonen,
**Grassmannian Packings from Orbits of Projective Group Representations,***Asilomar Conference on Signals, Systems and Computers*, pp. 478--482, Nov. 2012. - O. Tirkkonen and R. Jäntti,
**On alpha-Proportional Fair Packet Scheduling in OFDMA downlink,***Allerton Conference on Communication, Control, and Computing*, pp. 241--245, Oct. 2012. - Joonas Pääkkönen, Prathapasinghe Dharmawansa, Camilla Hollanti, Olav Tirkkonen,
**Distributed Storage for Proximity Based Services,***Swedish Communications Technologies Workshop*, pp. 30--35, Oct 2013. - P. Amin, V. P. K. Ganesan, O. Tirkkonen,
**Bridging Interference Barriers in Self-organized Synchronization,***IEEE Internat. Conf. on Self-Adaptive and Self-Organizing Systems*, pp. 109--118, Sept 2012. - U. Oruthota and O. Tirkkonen,
**I/Q Imbalance Compensation in Precoded MIMO-OFDMA Systems,***15th Internat. Symp. Wireless Personal Multimedia Commun. (WPMC)*, pp. 291--295., Sept. 2012. - H.-L. Määttänen and O. Tirkkonen,
**Simple Zero Interference Transmissions to Users with Rank Deficient Channels,***15th Internat. Symp. Wireless Personal Multimedia Commun. (WPMC)*, pp. 281--285, Sept. 2012. - L. Wei, P. Dharmawansa and O. Tirkkonen,
**Locally Best Invariant Test for Multiple Primary User Spectrum Sensing,***Internat. Conf. on Cognitive Radio Oriented Wireless Networks (CrownCom)*, pp. 367--372, June 2012. - F. Ahmed, A. Dowhuszko, and O. Tirkkonen,
**Distributed Algorithm for Downlink Resource Allocation in Multicarrier Small Cell Networks,***IEEE ICC, Workshop on small cell networks*, pp. 6802-6808, June 2012. - L. Wei, O. Tirkkonen, P. Dharmawansa and M. McKay,
**On the Exact Distribution of the Scaled Largest Eigenvalue,***IEEE ICC*, pp. 2422--2426, June 2012. - R.-A. Pitaval and O. Tirkkonen,
**Incorporating Stiefel Geometry in Codebook Design and Selection for Improved Base Station Cooperation,***IEEE VTC--Spring*, 5 pp., May 2012. -
H.-L. Määttänen and O. Tirkkonen,
**Sum Rate Maximizing Zero Interference Linear Multiuser MIMO Transmission,***IEEE VTC--Spring*, 5 pp., May 2012.