MIMO Sphere Decoding With Successive Interference Cancellation for Two-Dimensional Non-Uniform Constellations

[EN] Non-uniform constellations (NUCs) have been introduced to improve the performance of quadrature amplitude modulation constellations. 1D-NUCs keep the squared shape, while 2D-NUCs break that constraint to provide robustness. An impending problem with multiple-input multiple-output (MIMO) is the optimum demapping complexity, which grows exponentially with the number of antennas and the constellation order. Some well-known sub-optimum MIMO demappers, such as soft fixed-complexity sphere decoders (SFSD), can reduce that complexity. However, SFSD demappers do not work with the 2D-NUCs, since they perform a quantization step in separated I/Q components. In this letter, we provide an efficient solution for the 2D-NUCs based on Voronoi regions. Both complexity implications and SNR performance are also analyzed.This work was partially supported by the Ministry of Economy and Competitiveness of Spain (TEC2014-56483-R), co-funded by the European FEDER fund.Barjau, C.; Fuentes, M.; Shitomi, T.; Gomez-Barquero, D. (2017). MIMO Sphere Decoding With Successive Interference Cancellation for Two-Dimensional Non-Uniform Constellations. IEEE Communications Letters. 21(5):1015-1018. doi:10.1109/LCOMM.2017.2653775S1015101821

Point-to-Multipoint Communication Enablers for the Fifth Generation of Wireless Systems

(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.[EN] 3GPP has enhanced the point-to-multipoint (PTM) communication capabilities of 4G LTE in all releases since the adoption of eMBMS in Release-9. Recent enhancements cover not only television services, but also critical machine-type and vehicular communications, following the backward-compatibility design philosophy of LTE. This article discusses the opportunity in the design and standardization of 5G to break with the existing paradigm for PTM transmissions in 4G LTE, where broadcast PTM transmissions were initially conceived as an add-on and pre-positioned service. 5G brings the opportunity to incorporate PTM capabilities as built-in delivery features from the outset, integrating point-to-point and PTM modes under one common framework and enabling dynamic use of PTM to maximize network and spectrum efficiency. This approach will open the door to completely new levels of network management and delivery cost efficiency. The article also discusses the implications of PTM for network slicing to customize and optimize network resources on a common 5G infrastructure to accommodate different use cases and services taking into account user densityThis work was supported in part by the European Commission under the 5G-PPP project Broadcast and Multicast Communication Enablers for the Fifth-(H2020-ICT-2016-2 call, grant number 761498). The views expressed in this contribution are those of the authors and do not necessarily represent the project.Generation of Wireless Systems 5G-XcastGomez-Barquero, D.; Navratil, D.; Appleby, S.; Stagg, M. (2018). Point-to-Multipoint Communication Enablers for the Fifth Generation of Wireless Systems. IEEE Communications Standards Magazine. 2(1):53-59. https://doi.org/10.1109/MCOMSTD.2018.170006953592

MIMO Scattered Pilot Performance and Optimization for ATSC 3.0

(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this[EN] ATSC 3.0 is the latest digital terrestrial television (DTT) standard, and it allows a higher spectral efficiency and/or a transmission robustness with multiple-input multiple-output (MIMO) technology compared to existing DTT standards. Regarding MIMO channel estimation, two pilot encoding algorithms known as Walsh-Hadamard encoding and Null Pilot encoding are possible in ATSC 3.0. The two MIMO pilot algorithms are standardized so as to have the same pilot positions and the same pilot boosting as single-input single-output, and the optimum pilot configuration has not been fully evaluated for MIMO. This paper focuses on the performance evaluation and optimization of the pilot boosting and the pilot patterns for two MIMO pilot encoding algorithms in ATSC 3.0 using physical layer simulations. This paper provides a great benefit to broadcasters to select the MIMO pilot configuration including pilot boosting, pilot pattern, and pilot encoding algorithm that better suits their service requirements. Several channel interpolation algorithms have been taken into account as a typical receiver implementation in both fixed SFN reception and mobile reception.This work was supported in part by the Ministry of Economy and Competitiveness of Spain under Grant TEC2014-56483-R, and in part by the European FEDER Fund.Shitomi, T.; Garro, E.; Murayama, K.; Gomez-Barquero, D. (2018). MIMO Scattered Pilot Performance and Optimization for ATSC 3.0. IEEE Transactions on Broadcasting. 64(2):188-200. https://doi.org/10.1109/TBC.2017.2755262S18820064

On the Provisioning of Mobile Digital Terrestrial TV Services to Vehicles with DVB-T

(c) 2012 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works[EN] Most of the DVB-T (Digital Video Broadcasting -Terrestrial) networks deployments worldwide have been designed for fixed rooftop antennas and high transmission capacity, not providing good coverage level for vehicular mobile reception. This letter analyzes how to combine different technical solutions, so far studied individually, in order to increase the robustness of the transmission for vehicular reception to provide in-band mobile services. In particular, we consider: receive antenna diversity, hierarchical modulation, and Application Layer Forward Error Correction (AL-FEC). Performance evaluation results have been obtained by means of simulations, laboratory tests, and field measurements in the commercial DVB-T network of the city of Valencia (Spain). The paper shows that the combined usage of these solutions can compensate the impairments caused by the mobility of the receivers, such as signal fast fading, Doppler shift, the poor coverage at ground level and the utilization of lower gain antennas; being possible to provide mobile DVB-T services to vehicles in networks dimensioned for fixed rooftop reception.This work was supported in part by the Spanish Ministry of Industry, Tourism and Commerce under the project AV-MOV (TSI-020301-2009-11).López Sánchez, J.; Gomez-Barquero, D.; Gozálvez Serrano, D.; Cardona Marcet, N. (2012). On the Provisioning of Mobile Digital Terrestrial TV Services to Vehicles with DVB-T. IEEE Transactions on Broadcasting. 58(4):642-647. https://doi.org/10.1109/TBC.2012.2202034S64264758

Semianalytical Approach to the PDF of SINR in HPHT and LPLT Single-Frequency Networks

(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this[EN] Single-frequency networks (SFN) are widely adopted in terrestrial broadcast networks based on high-power high-tower (HPHT) deployments. The mobile broadcasting standard Evolved Multimedia Broadcast Multicast Service (eMBMS) has been enhanced in Release 14 to enable SFN operation with larger CP duration which may allow for the deployment of large area SFNs and even the combined operation between HPHT and low-power low-tower (LPLT) cellular stations. The knowledge of the signal-to-interference-plus-noise ratio (SINR) distribution over an SFN area may facilitate the selection of transmission parameters according to the network topology. This paper presents a semianalytical method for the calculation of the SINR distribution in SFNs with low computational complexity compared to Monte Carlo simulations. The method, which builds on previous work developed for cellular communications, is applied to HPHT+LPLT SFNs and evaluated against different transmission and network parameters.This work was supported in part by the Ministerio de Educacion y Ciencia, Spain, under Grant TEC2014-56483-R, in part by European FEDER funds.Gimenez Gandia, JJ.; Sung, KW.; Gomez-Barquero, D. (2018). Semianalytical Approach to the PDF of SINR in HPHT and LPLT Single-Frequency Networks. IEEE Transactions on Vehicular Technology. 67(5):4173-4181. https://doi.org/10.1109/TVT.2018.2791347S4173418167

Scattered Pilot Performance and Optimization for ATSC 3.0

[EN] The next-generation U.S. digital terrestrial television (DTT) standard ATSC 3.0 is the most flexible DTT standard ever developed, outperforming the state-of-the-art digital video broadcasting-terrestrial 2nd generation (DVB-T2) standard. This higher flexibility allows broadcasters to select the configuration that better suits the coverage and capacity requirements per service. Regarding the selection of pilot patterns, whereas DVB-T2 provides eight different patterns with a unique pilot amplitude, ATSC 3.0 expands up to 16, with five different amplitudes per pattern. This paper focuses on the pilot pattern and amplitude performance and optimization for time and power multiplexing modes, time division multiplexing and layered division multiplexing (LDM), respectively, of ATSC 3.0. The selection of the optimum pilot configuration is not straightforward. On the one hand, the pilots must be sufficiently dense to follow channel fluctuations. On the other hand, as long as pilot density is increased, more data overhead is introduced. Moreover, this selection is particularly essential in LDM mode, because the LDM implementation in ATSC 3.0 requires that both layers share all the waveform parameters, including pilot pattern configuration. In addition, there is an error proportional to the channel estimate of the top layer that affects to the lower layer performance.This work was supported in part by the Institute for Information and Communications Technology (IITP) by the Korea Government (MSIP) (Development of Service and Transmission Technology for Convergent Realistic Broadcast) under Grant R0101-15-294, and in part by the Ministerio de Educación y Ciencia, Spain, by European FEDER Funds under Grant TEC2014-56483-R.Garro, E.; Gimenez, JJ.; Park, SI.; Gomez-Barquero, D. (2017). Scattered Pilot Performance and Optimization for ATSC 3.0. IEEE Transactions on Broadcasting. 63(1):282-292. https://doi.org/10.1109/TBC.2016.2630304S28229263

Wideband Broadcasting: A Power-Efficient Approach to 5G Broadcasting

(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this[EN] Efficient and flexible use of spectrum will be inherent characteristics of fifth-generation (5G) communication technologies with native support of wideband operation with frequency reuse 1, i.e. all transmit sites use all available frequency resources. Although not from the very first 5G release of 3GPP (Third Generation Partnership Project), it is expected that broadcast/multicast technology components will later be added and fully integrated in the 5G system. The combination of both wideband and frequency reuse 1 may provide significant gains for broadcast transmissions in terms of energy efficiency, since it is more efficient to increase capacity by extending the bandwidth rather than increasing the transmit power over a given bandwidth. This breaks with the traditional concept of terrestrial broadcast frequency planning, and paves the way to new potential uses of UHF (Ultra High Frequency) spectrum bands for 5G broadcasting. This paper provides an insight into the fundamental advantages in terms of capacity, coverage as well as power saving of wideband broadcast operation. The role of the network deployment, linked to frequency reuse in the UHF band, and its influence in the performance of a Wideband Broadcasting system are discussed. The technical requirements and features that would enable such power-efficient solution are also addressed.This work was supported in part by the European Commission under the 5G-PPP project 5G-Xcast (H2020-ICT-2016-2 call, grant number 761498). The views expressed in this contribution are those of the authors and do not necessarily represent the project. This work was also partially supported by the Ministerio de Educacion y Ciencia, Spain (TEC2014-56483-R), co-funded by European FEDER funds.Gimenez Gandia, JJ.; Gomez-Barquero, D.; Mogarde, J.; Stare, E. (2018). Wideband Broadcasting: A Power-Efficient Approach to 5G Broadcasting. IEEE Communications Magazine. 56(3):119-125. https://doi.org/10.1109/MCOM.2018.170067511912556

Information-Theoretic Analysis and Performance Evaluation of Optimal Demappers for Multi-Layer Broadcast Systems

(c) 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this[EN] Multi-layer broadcast systems distribute services across time and frequency domain by means of power-division multiplexing. Successive interference cancelation is required, in general, in order to extract the content of all services. For a low-complexity implementation, the receiver can obtain the strongest (top-layer) signal assuming underlying signals to behave like thermal noise. The thermal noise assumption may not be valid under certain conditions and a more accurate characterization of the interference could bring improved performance. This paper analyzes the validity of the noise-like assumption considering the power ratio between signals and the required carrier-to-noise ratio for error-free reception. The main contribution of the paper is the proposal of a demapping algorithm that exploits the knowledge of the constellation of underlying signals. Generalized mutual information, performance evaluation, and complexity analysis are provided with the additive white Gaussian noise-like assumptions and with the proposed alternative in order to assess the potential performance improvements that can be achieved.This work was supported by in part by the Ministerio de Educacion y Ciencia, Spain under Grant TEC2014-56483-R, and in part by the European FEDER Funds.Garro, E.; Gimenez Gandia, JJ.; Klenner, P.; Gomez-Barquero, D. (2018). Information-Theoretic Analysis and Performance Evaluation of Optimal Demappers for Multi-Layer Broadcast Systems. IEEE Transactions on Broadcasting. 64(4):781-790. https://doi.org/10.1109/TBC.2018.2799300S78179064

5G Radio Access Networks Enabling Efficient Point-to-Multipoint Transmissions

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] The first release of 5th Generation (5G) technology from 3rd Generation Project Partnership (3GPP) Rel'15 has been completed in December 2018. An open issue with this release of standards is that it only supports unicast communications in the core network and Point-To-Point (PTP) transmissions in the Radio Access Network (RAN), and does not support multicast/broadcast communications and Point-To-Multipoint (PTM) transmissions, which are 3GPP system requirements for 5G applications in a number of vertical sectors, such as Automotive, Airborne Communications, Internet-of-Things, Media & Entertainment, and Public Warning & Safety systems. In this article, we present novel mechanisms for enhancing the 5G unicast architecture with minimal footprint, to enable efficient PTM transmissions in the RAN, and to support multicast communications in the Rel'15 core as an in-built delivery optimization feature of the system. This approach will enable completely new levels of network management and delivery cost-efficiency.This work was supported in part by the European Commission under the 5G Infrastructure Public Private Partnership project "5G-Xcast: Broadcast and Multicast Communication Enablers for the Fifth Generation of Wireless Systems" (H2020-ICT-2016-2 call, grant 761498). The views expressed here are those of the authors and do not necessarily represent the project.Säily, M.; Barjau, C.; Navrátil, D.; Prasad, A.; Gomez-Barquero, D.; Tesema, FB. (2019). 5G Radio Access Networks Enabling Efficient Point-to-Multipoint Transmissions. IEEE Vehicular Technology Magazine. 14(4):29-37. https://doi.org/10.1109/MVT.2019.2936657S293714

Efficient HDTV and 3DTV services over DVB-T2 using Multiple PLPs with Layered Media

[EN] The high bit rates of high-definition or 3D services require a huge share of the valuable terrestrial spectrum, especially when targeting wide coverage areas. This article describes how to provide future services with the state-of-the-art digital terrestrial TV technology DVB-T2 in a flexible and cost-efficient way. The combination of layered media such as the scalable and 3D extension of the H.264/AVC or emerging H.265/HEVC format with the physical layer pipes feature of DVB-T2 enables flexible broadcast of services with differentiated protection of the quality layers. This opens up new ways of service provisioning such as graceful degradation for mobile or fixed reception. This article shows how existing DVB-T2 and MPEG-2 transport stream mechanisms need to be configured for offering such services over DVB-T2. A detailed description of the setup of such services and the involved components is given.Hellge, C.; Wiegand, T.; Guinea Torre, E.; Gomez-Barquero, D.; Schierl, T. (2013). Efficient HDTV and 3DTV services over DVB-T2 using Multiple PLPs with Layered Media. IEEE Communications Magazine. 51(10):76-82. doi:10.1109/MCOM.2013.6619569S7682511