Academic Journal of Computing & Information Science, 2023, 6(5); doi: 10.25236/AJCIS.2023.060506.
Zhizheng Gao, Zhiling Tang, Zhou Jiang, Li Xu
School of Information and Communication, Guilin University of Electronic Technology, Guilin, Guangxi, China
OFDM is one of the most widely used multi-carrier modulation technologies in wireless communication. However, in the case of high mobility, the orthogonality between sub-carriers is destroyed due to the existence of time selective fading, and the performance of OFDM system is greatly affected. In order to reduce this effect, the data can be pre-coding before OFDM modulation. The pre-coding technique adopted in this paper is Walsh-Hadamard transform (WHT). The data are distributed evenly on all sub-carriers by WHT operation, which avoids the problem of data loss caused by some sub-carriers which can’t be recovered. In this paper, the design scheme of WHT-OFDM system is first proposed, then the modulation and demodulation module of the system is designed using the Verilog HDL language, and then the simulation verification of the design is completed. The results proved that the designed WHT-OFDM system can be successfully implemented on FPGA.
OFDM; High mobility; Wireless communication; WHT; FPGA
Zhizheng Gao, Zhiling Tang, Zhou Jiang, Li Xu. FPGA Implementation of a WHT-OFDM Modem. Academic Journal of Computing & Information Science (2023), Vol. 6, Issue 5: 39-48. https://doi.org/10.25236/AJCIS.2023.060506.
 Mecwan A, Shah D. Implementation of OFDM transceiver on FPGA[C]. 2013 Nirma University International Conference on Engineering (NUiCONE). IEEE, 2013:1-5.
 Wang S, Zhu S, Zhang G. A Walsh-Hadamard coded spectral efficient full frequency diversity OFDM system [J]. IEEE transactions on communications, 2010, 58(1):28-34.
 Kishk S, Mansour A, Eldin M. Implementation of an OFDM system using FPGA[C]. 2009 National Radio Science Conference. IEEE, 2009:1-9.
 Jayan G, Nair A K. Performance analysis of filtered OFDM for 5G[C]. 2018 international conference on wireless communications, signal processing and networking (WiSPNET). IEEE, 2018: 1-5.
 Dlugaszewski Z, Wesolowski K. WHT/OFDM-an improved OFDM transmission method for selective fading channels [C]. IEEE Benelux Chapter on Vehicular Technology and Communications. Symposium on Communications and Vehicular Technology. SCVT-2000. Proceedings (Cat. No. 00EX465). IEEE, 2000:144-149.
 Sravanti T, Vasantha N. Performance analysis of precoded PTS and SLM scheme for PAPR reduction in OFDM system[C]. 2017 International Conference on Innovations in Electrical, Electronics, Instrumentation and Media Technology (ICEEIMT). IEEE, 2017:255-260.
 Farzamnia A, Moung E, Ang W H, et al. Investigation on PAPR Reduction in OFDM System[C]. 2018 10th International Conference on Computational Intelligence and Communication Networks (CICN). IEEE, 2018:45-49.
 Aboltins A, Litvinenko A, Misans P. Parametric linear precoding for OFDM using Generalized Unitary Rotation [C]. 2016 15th Biennial Baltic Electronics Conference (BEC). IEEE, 2016:131-134.
 Ayduslu E, Tören O D, Aydın Y, et al. A novel approach for improving carrier frequency offset tracking performance of frequency domain channel equalizer employed in OFDM systems [C]. 2017 40th International Conference on Telecommunications and Signal Processing (TSP). IEEE, 2017: 190-194.
 Lei Z, Wu Y, Ho C K, et al. Iterative detection for Walsh-Hadamard transformed OFDM [C]. The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring. IEEE, 2003, 1: 637-640.
 Shete S, Bhide G, Jadhav M. WHT and Double WHT: An effective PAPR reduction approach in OFDM [C]. 2016 IEEE International Conference on Advances in Electronics, Communication and Computer Technology (ICAECCT). IEEE, 2016:172-175.
 Ren A, Luo M, Hu F. FPGA implementation of an OFDM modem [C]. IET International Communication Conference on Wireless Mobile and Computing (CCWMC 2009). IET, 2009:761-764.