Journal papers

2022 – 2021 – 2020 – 2019 – 2018 – 2017 – 2016 – 2015 – 2014 – 2013 – 2012 – 2011 – 2010 – 2009 – 2008 – 2007 – 2006 – 2005 – 2003 – 2002 – 2001

  • 2022
    • J. Valls, V. Torres, A. Pérez-Pascual and V. Almenar, «Hardware Architecture of a QAM Receiver for Short-Range Optical Communications,» in Journal of Lightwave Technology, 2022. (pdf)
    • P. Salvador, J. Valls, M. J. Canet, V. Almenar and J. L. Corral, «On the Performance and Power Consumption of Bias-T Based Drivers for High Speed VLC,» in Journal of Lightwave Technology, vol. 40, no. 18, pp. 6078-6086, 15 Sept., 2022. (pdf)
    • P. Salvador, J. Valls, J. L. Corral, V. Almenar and M. J. Canet, «Linear Response Modeling of High Luminous Flux Phosphor-Coated White LEDs for VLC,» in Journal of Lightwave Technology, vol. 40, no. 12, pp. 3761-3767, 15 June, 2022. (pdf)
    • D.N. Nguyen, L. Vallejo, V. Almenar, B. Ortega, P.T. Dat, S.T. Le, J. Bohata, S. Zvanovec, «Full-duplex transmission of multi-Gb/s subcarrier multiplexing and 5G NR signals in 39 GHz band over fiber and space,» in Applied Optics, vol. 61, no. 5, pp. 1183-1193, Feb., 2022. (pdf)
  • 2021
    • L. Vallejo, J. Mora, D.N. Nguyen, J. Bohata, V.Almenar, S. Zvanovec, B. Ortega, «On the 40 GHz Remote Versus Local Photonic Generation for DML-Based C-RAN Optical Fronthaul,» in Journal of Lightwave Technology, vol. 39, no. 21, pp. 6712-6723, Nov. 2021. (pdf)
    • J. Valls, F. Garcia-Herrero, N. Raveendran and B. Vasic, «Syndrome-Based Min-Sum vs OSD-0 Decoders: FPGA Implementation and Analysis for Quantum LDPC Codes,» in IEEE Access, vol. 9, pp. 138734-138743, Oct. 2021. (pdf)
    • J.A. Apolo, B. Ortega, V. Almenar, «Hybrid POF/VLC Links Based on a Single LED for Indoor Communications,» in Photonics, vol. 8, no. 7, July 2021. (pdf)
  • 2020
    • L. Villarejo, B. Ortega, D.N. Nguyen, J. Bohata, V. Almenar, S. Zvanovec, «Usability of a 5G Fronthaul Based on a DML and External Modulation for M-QAM Transmission Over Photonically Generated 40 GHz,» in IEEE Access, vol. 8, pp. 223730-223742, Dec,. 2020. (pdf)
    • A. Pérez-Pascual, J. S. Bruno, V. Almenar and J. Valls, «A Computational Efficient Nyquist Shaping Approach for Short-Reach Optical Communications,» in Journal of Lightwave Technology, vol. 38, no. 7, pp. 1651-1658, 1 April, 2020. (pdf)
    • Vallejo-Castro, Luis; Ortega Tamarit, Beatriz; Bohata, Jan; Zvanovec, Stanislav; Almenar Terre, Vicenç, «Impact of Thermal-Induced Turbulent Distribution Along FSO Link on Transmission of Photonically Generated mmW Signals in the Frequency Range 26–40 GHz,» in IEEE Photonics Journal, vol. 12, no. 1, pp. 1-9, Feb. 2020, Art no. 5500309. (pdf)
    • Vallejo-Castro, Luis; Ortega Tamarit, Beatriz; Bohata, Jan; Zvanovec, Stanislav; Almenar Terre, Vicenç. «Photonic multiple millimeter wave signal generation and distribution overreconfigurable hybrid SSMF/FSO links». Optical Fiber Technology, vol. 54, Jan. 2020, ISSN 1068-5200. (pdf)
  • 2019
    • J. Valls, V. Torres, M.J. Canet, F. García-Herrero, “A Test Vector Generation Method Based on Symbol Error Probabilities for Low-Complexity Chase Soft-Decision Reed-Solomon Decoding,” IEEE Transactions on Circuits and Systems I Regular Papers, N.6, Vol. 66, pp. 2198-2207, 2019. (pdf)
    • V. Torres, J. Valls, M.J. Canet, F. García-Herrero, “Soft-Decision Low-Complexity Chase Decoders for the RS(255,239) Code,” Electronics, No. 8, pp. 1- 13. Jan. 2019. (pdf)
    • JM. Català, J.O. Lacruz, F. García-Herrero, J. Valls, D.Declerq, “Second Minimum Approximation for Min-Sum Decoders Suitable for High-Rate LDPC Codes,” Circuits, Systems, and Signal Processing, Vol. 38, pp. 5068-5080, 2019. (pdf)
    • G. Perrone, J. Valls, V. Torres, F. García-Herrero, “Reed–Solomon Decoder based on a Modified ePIBMA for Low-Latency 100 Gbps Communication Systems,” Circuits, Systems, and Signal Processing, Vol. 38, pp. 1793-1810, 2019. (pdf)
    • J.S. Bruno, V. Almenar, J. Valls, “FPGA implementation of a 10 GS/s variablelength FFT for OFDM-based optical communication systems,” Microprocessors and Microsystems. 64, pp.195 – 204, Feb. 2019. (pdf)
  • 2018
    • J.S. Bruno, V. Almenar, J. Valls, J.L. Corral, “Real-time 20.37 Gb/s optical OFDM receiver for PON IM/DD systems,” Optic Express, Vol.26, No.15, pp. 18817-18831, Jul. 2018. (pdf)
  • 2017
    • Medina-Sevila, Pau; Almenar Terre, Vicenç; Corral, Juan L.. (2017) «Transmission Over SSMF at 850 nm: Bimodal Propagation and Equalization». Journal of Lightwave Technology, 19 (35), 4125 – 4136. (pdf)
    • V. Torres, J. Valls and R. Lyons, «Fast- and Low-Complexity atan2(a,b) Approximation [Tips and Tricks],» in IEEE Signal Processing Magazine, vol. 34, no. 6, pp. 164-169, Nov. 2017. (pdf)
    • V. Torres, J. Valls, “A fast and low-complexity operator for the computation of the arctangent of a complex number,” IEEE Transactions on Very Large Scale Integration, Vol.25, No.9, pp. 2663-2667, Sept. 2017. (pdf)
    • V. Torres, J. Valls, M.J. Canet, “Optimized CORDIC-based atan2 computation for FPGA implementations,” IET Electronics Letters, Vol. 53, Issue 19, pp. 1294-1296 Sept. 2017. (pdf)
  • 2016
    • J.O. Lacruz, F. Garcia-Herrero, M.J. Canet, J. Valls, “High-performance NBLDPC decoder with reduction of message exchange,” IEEE Transactions on Very Large Scale Integration, Vol.24, No.11, pp. 1950-1961, Nov. 2016. (pdf)
    • J.O. Lacruz, F. Garcia-Herrero, M.J. Canet, J. Valls, “Reduced-complexity non-binary LDPC decoder for high-order Galois fields based on Trellis Min-Max algorithm,” IEEE Transactions on Very Large Scale Integration, Vol.24, No.11, pp. 2643-2653, Feb. 2016. (pdf)
  • 2015
    • J.S. Bruno, V. Almenar, J. Valls, J.L. Corral,“Low-Complexity Time Synchronization Algorithm for Optical OFDM PON System Using a Directly Modulated DFB Laser, ” Journal of Optical Communications and Networking, Vol.7, No. 11, pp.1025-1033, Nov. 2015 (pdf)
    • J.O. Lacruz, F. Garcia-Herrero, J. Valls,“Reduction of complexity for Non-binary LDPC decoders with compressed messages, ” IEEE Transactions on Very Large Scale Integration, Vol.23, No.11, pp.2676-2679, Nov. 2015
    • P. Medina, V. Almenar, J.L. Corral,“Combined Data Detection Scheme for Zero-Padded OFDM Signals in MMF Links , ” IEEE Photonics Technology Letters, Vol. 27, No. 16, pp. 1753-1756, Jul. 2015
    • J.O. Lacruz, F. Garcia-Herrero, D. Declercq, J. Valls, «One Minimum Only Trellis Decoder for Non-Binary Low-Density Parity-Check Codes, « IEEE Transactions on Circuits and Systems I, Vol.62, No.1, pp.177-184, Jan. 2015
    • J.O. Lacruz, F. Garcia-Herrero, D. Declercq, J. Valls, «Simplified Trellis Min-Max Decoder Architecture for Nonbinary Low-Density Parity-Check Codes, « IEEE Transactions on Very Large Scale Integration, Vol.23, No.9, pp.1783-1792, Sep. 2015
  • 2014
    • J.M. Catala, F. Garcia-Herrero, J. Valls, K. Liu, S. Lin, “Reliability-based iterative decoding algorithm for LDPC codes with low variable-node degree, ” IEEE Communications Letters, Vol.18, No.12, pp.2065-2268, Dic. 2014
    • F. Garcia-Herrero, E. Li, D. Declercq, J. Valls, «Multiple-Vote Symbol-Flipping Decoder for Non-Binary LDPC Codes, « IEEE Transactions on Very Large Scale Integration, Vol.22, No.11, pp.2256-2267, Nov. 2014
    • P. Medina, V. Almenar, J.L. Corral,“Evaluation of optical ZP-OFDM transmission performance in multimode fiber links, ” Optics Express, Vol. 22, No. 1, pp. 1008-1017, Ene. 2014
    • F. Garcia-Herrero, D. Declercq, J.Valls, “Non-Binary LDPC Decoder based on Symbol Flipping with Multiple Votes, ” IEEE Communications Letters, Vol.18 No.5, pp.749-752, Jun.2014
    • F. Angarita, J. Valls, V. Almenar, V. Torres, «Reduced-Complexity Min-Sum Algorithm for Decoding LDPC Codes with Low Error-Floor, «, IEEE Transactions on Circuits and Systems I, Vol.61, No.7, pp.2150-2158, Jul. 2014
    • F. Garcia-Herrero, M.J. Canet, J. Valls, «Non-Binary LDPC Decoder Based on Simplified Enhanced Generalized Bit Flipping Algorithm, « IEEE Transactions on Very Large Scale Integration, Vol.22, No.6, pp.1455-1459, Jun. 2014
  • 2013
    • F. Garcia-Herrero, M.J. Canet, J. Valls, “Architecture of Generalized Bit-Flipping Decoding for High-Rate Non-binary LDPC Codes, ” Circuits, Systems, and Signal Processing, Vol. 32, pp: 727-741, 2013
    • G.A. Jaquenod, J. Valls, J. Siman, “Efficient FPGA Hardware Reuse in a Multiplierless Decimation Chain, ” International Journal of Reconfigurable Computing, accepted for publication in 2013
  • 2012
    • S. Roger, A. Gonzalez, V. Almenar and G. Matz, «An Efficient Fixed-Complexity Sphere Decoder with Quantized Soft Outputs,» in IEEE Communications Letters, vol. 16, no. 11, pp. 1828-1831, November 2012. (pdf)
    • Sandra Roger, Carla Ramiro, Alberto Gonzalez, Vicenç Almenar, Antonio M. Vidal, “An Efficient GPU Implementation of Fixed-Complexity Sphere Decoders for MIMO Wireless Systems, ” Integrated Computer-Aided Engineering, Vol.19, No.4, pp.341-350, 2012
    • Sandra Roger, Carla Ramiro, Alberto Gonzalez, Vicenç Almenar, Antonio M. Vidal, “Fully parallel GPU implementation of a fixed-complexity soft-output MIMO detector, ” IEEE Trans. on Vehicular Technology, Vol.61, No.6, pp.3796-3800, Oct.2012
    • F. Angarita, J. Marin-Roig, V. Almenar, J. Valls, “Low-complexity LDPC decoding algorithm for high-speed VLSI implementation, ” IET Communications, Vol.6, No.16, pp.2575-2581, Nov.2012
    • R. Gutierrez, V. Torres, J.Valls, “Hardware Architecture of a Gaussian Noise Generator Based on Inversion Method, ” IEEE Transactions on Circuits & Systems II, Vol.59, No.8, pp.501-505, 2012
    • F. Garcia-Herrero, M.J. Canet, J.Valls, M.Flanagan, “Serial Symbol-Reliability Based Algorithm For Decoding Non-Binary LDPC Codes, ” IEEE Communications Letters, Vol.16 No.6, pp.909-912, Jun.2012
    • M.J. Canet, J.Valls, V.Almenar, J. Marin-Roig, “FPGA implementation of an OFDM-based WLAN receiver, ” Microprocessors and Microsystems, Vol.36, No.3, pp.232-244, 2012
    • M.J. Canet, V.Almenar, S. Flores, J.Valls, “Low complexity time synchronization algorithm for OFDM systems with repetitive preambles, ” Journal of Signal Processing Systems, Vol.68, No.3, pp.287-301, Sep.2012
    • F. Angarita, T.Sansaloni, A. Perez-Pascual, J. Valls, “Modifed Shuffled Based Architecture for High Throughput Decoding of LDPC Codes, ” Journal of Signal Processing Systems, Vol.68, No.2, pp.139-149, Aug.2012
  • 2011
    • Sandra Roger, Alberto Gonzalez, Vicenç Almenar, Antonio M. Vidal, “Practical aspects of preprocessing techniques for K-best tree search MIMO detectors, ” Computers & Electrical Engineering, Vol.37, No.4, pp.451-460, Jul.2011
    • V. Almenar, A. Girona, S. Flores, J. Marin-Roig, “Transmit diversity scheme for OFDM systems using the odd DFT, ” IEICE Transactions on Communications, Vol.E94-B, No.8, pp.2411-2413, Aug.2011
    • F. Garcia-Herrero, M.J. Canet, J. Valls, P.K. Meher, “High-Throughput Interpolator Architecture for Low-Complexity Chase Decoding of RS Codes, ” IEEE Transactions on Very Large Scale Integration,Vol.20, No.3, pp.568-573, Mar.2012
    • F. Angarita, T.Sansaloni, M.J.Canet, J. Valls, “Improved Sliced Message Passing Architecture for High Throughput Decoding of LDPC Codes, ” Journal of Signal Processing Systems, Vol.66, No.2, pp.99-104, Feb.2012
    • F. Garcia-Herrero, J. Valls, P.K. Meher, “High speed RS(255,239) decoder based on LCC decoding, ” Circuits, Systems, and Signal Processing, Vol.30, No.6, pp.1643-1669, May.2011
    • R. Gutierrez, J. Valls, “Low cost Hardware Implementation of logarithm approximation, ” IEEE Transactions on Very Large Scale Integration, Vol.19, No.12, pp.2326-2330, Dic.2011
    • F. J. Martínez-Zaldívar, A. M. Vidal-Maciá, A. Gonzalez and V. Almenar, “Tridimensional block multiword LDPC decoding on GPUs, ” The Journal of Supercomputing, Vol.58, pp.514-322, 2011
  • 2010
    • Sandra Roger, Alberto Gonzalez, Vicenç Almenar, Antonio M. Vidal, “Extended LLL algorithm for efficient signal precoding in multiuser nication systems, ” IEEE Communications Letters, Vol.14, No.3, Mar.2010
    • R. Gutierrez, V. Torres, J. Valls, “FPGA implementation of atan(Y/X) based on Logarithmic transformation and LUT-based techniques, ” Journal of Systems Architecture, Vol.56, pp.588-596, Nov.2010
  • 2009
    • Pramod K. Meher, Javier Valls, Tso-Bing Juang, K. Sridharan, and Koushik Maharatna, “50 Years of CORDIC: Algorithms, Architectures and Applications, ” IEEE Transactions on Circuits and Systems I, Vol.56, No.9, Sep.2009
    • Sandra Roger, Alberto Gonzalez, Vicenç Almenar, Antonio M. Vidal, “MIMO Channel Matrix Condition Number Estimation and Threshold Selection for Combined K-Best Sphere Decoders, ” IEICE Transactions on Communications Vol.E92-B (4), pp.1380-1383, Apr.2009
    • F. Angarita, A. Almenar, M.J. Canet, T. Sansaloni, J.Valls, “Power consumption reduction in a Viterbi Decoder for OFDM-WLAN, ” Journal of Circuits, Systems and Computers Vol.18, No.7, pp.1333-1337, Nov. 2009
    • A. Perez-Pascual, V. Torres, T. Sansaloni, V. Almenar, J.Valls, “Design of Power and Area Efficient Digital Down-converters for Broadband Communications Systems, ” Journal of Signal Processing Systems Vol.56, No.1, pp.35-40, Jul.2009
    • R. Gutierrez, J.Valls, “Low-power FPGA-implementation of atan(Y/X) using Look-Up Table methods for communication applications, ” Journal of Signal Processing Systems Vol.56, No.1, pp.26-33, Jul.2009
    • V. Torres, A. Perez-Pascual, T. Sansaloni, J.Valls, “Design and FPGA-implementation of a high performance timing recovery loop for broadband communications, ” Journal of Signal Processing Systems Vol.56, No.1, pp.17-23, Jul.2009
  • 2008
    • F. Angarita, M.J. Canet, T. Sansaloni, A. Perez-Pascual, J.Valls, “Efficient mapping of CORDIC Algorithm for OFDM-based WLAN, ” Journal of Signal Processing Systems,Vol.52, No.2, pp.181-191, Aug.2008
    • F. Angarita, M.J. Canet, T. Sansaloni, V. Almenar, J.Valls, “Architectures for the implementation of a OFDM-WLAN Viterbi Decoder, ” Journal of Signal Processing Systems, Vol.52, No.1, pp.35-44, Jul.2008
  • 2007
    • T. Sansaloni, A. Perez-Pascual, V. Torres, J.Valls, “Scheme for reducing the storage requirements of FFT twiddle factors on FPGAs, ” Journal of VLSI Signal Processing, Vol.47, pp.105-115, May.2007
    • T. Sansaloni, A. Perez-Pascual, V. Torres, V. Almenar, J. Toledo, J.Valls, “FFT Spectrum Analyzer Project for Teaching Digital Signal Processing with FPGA devices, ” IEEE Trans. on Education, Nov.2007
  • 2006
    • F. Castells, V. Almenar, “Closed-form expression for the BER of m-QAM-OFDM systems over time and frequency-selective wireless channels, ” International Journal of Communication Systems, Vol.19(8), pp.861-876, Oct.2006
    • J.Valls, T. Sansaloni, A. Perez-Pascual, V. Torres, V. Almenar, “The use of CORDIC in Software Defined Radios: A tutorial, ” IEEE Communications Magazine, Vol.44, No.9, Sep.2006
  • 2005
    • T. Sansaloni, A. Perez-Pascual, V. Torres, J. Valls, “Efficient pipeline FFT processor form MIMO-OFDM systems, ” Electronic Letters, Vol.41, No.19, Sep.2005
  • 2003
    • T. Sansaloni, A. Perez-Pascual, J. Valls, “Area-efficient FPGA-based FFT processor, ” Electronic Letters, Vol.39, No.19, Sep.2003
    • J. Valls and E. Boemo, “Efficient FPGA-Implementation of two’s complement digit-serial/parallel multipliers, ” IEEE Transactions on Circuits and Systems II, Vol.50, No.6, Jun.2003
    • F. Cardells, J. Valls, “Area-Optimized Implementation of Quadrature Direct Digital Frequency Synthesizers on LUT-based FPGAs, ” IEEE Transactions on Circuits and Systems II, Vol.50, No.3, Mar.2003
    • T. Sansaloni, J. Valls, K.K. Parhi, “Digit-serial Complex-Number Multipliers on FPGAs, ” Journal of VLSI Signal Processing, special issue on Computer Arithmetic and Applications, Vol.33, No.1-2, pp.105-115, Jan.2003
  • 2002
    • J. Valls, M. Kuhlmann, K.K. Parhi, “Evaluation of CORDIC Algorithms for FPGA design, ” Journal of VLSI Signal Processing, Vol.32, No.3, pp.207-222, Nov.2002
  • 2001
    • F. Cardells, J. Valls, “Optimization of direct digital frequency synthesizers based on CORDIC, ” Electronic Letters, Vol.37, No.21, pp.1278-1280, Oct.2001