Exploring Raised Cosine Filtering for Signal Integrity and ISI Mitigation in Digital Communication Systems’
Keywords:
Raised Cosine Filtering, Inter-Symbol Interference (ISI), Digital Communication Systems, Bit Error Rate (BER), Peak-to-Average Power Ratio (PAPR)Abstract
In high-speed networks such as 4G/5G, bandwidth constraints are a major challenge to digital communication systems, where Inter-Symbol Interference (ISI) is a major problem. The present paper addresses the application of raised cosine filtering to eliminate ISI and improve signal integrity in the context of several modulation methods (BPSK, QPSK and M-PSK). By using MATLAB simulations, a series of roll-off values (0.1 to 0.9) were studied, with the performance measured in terms of Bit Error rate (BER), peak-to-average power ratio (PAPR) and signal quality, represented by eye diagrams. The work concludes that a higher roll-off factor has led to a better reduction of ISI and signal clearance although there is an expense of using more bandwidth. The findings point out to a trade-off between bandwidth efficiency and ISI mitigation which is useful in the design of optimized filters in contemporary high-speed communication systems. Such results can be applied to the creation of more efficient filtering methods to realistic networks such as 4G/5G and Wi-Fi, which can provide useful information to the designers of the communication systems.
References
Ahmed, R. (2016). Improving the Spectral Efficiency of OFDM System Using Raised Cosine Filter. International Journal of New Technology and Research, 2(6), 263487.
Alagha, N. S., & Kabal, P. (2002). Generalized raised-cosine filters. IEEE transactions on Communications, 47(7), 989-997.
Alnajjar, K. A., Ansari, S., Mahmoud, M., Alraeesi, M., Alhmoudi, M., Alaskar, S., ... & Hussain, A. (2025, February). Adaptive Modulation and Coding Techniques for Next-Generation Wireless Networks. In 2025 IEEE 22nd International Multi- Conference on Systems, Signals & Devices (SSD) (pp. 50-57). IEEE.
Ansari, M.S., & Oommen, M. (2014). Review on Design and Implementation of DSSS-CDMA Transmitter using HDL with Raised Cosine Filter to Minimize ISI. International Journal of Computer Science and Mobile Computing, 3(3), 837-844.
Banerjee, P., Chatterjee, S., Ghosh, R., Bhattacharya, A., & Shil, R. (2024). Finding the optimum roll-off rate of a raised cosine filter at the receiver to achieve the lowest bit error rate for a given modulation order and a given energy/bit normalized noise ratio. International Journal of Advanced Networking and Applications, 15(04), 179- 184.
Bedeer, E., Ahmed, M. H., & Yanikomeroglu, H. (2017). A very low complexity successive symbol-by-symbol sequence estimator for faster-than-Nyquist signaling. IEEE Access, 5, 7414-7422.
Chattopadhyay, S., & Sanyal, S. K. (2009). Comparison of Performance Metrics for QPSK and OQPSK Transmission Using Root Raised Cosine and Raised Cosine Pulse shaping Filters for Applications in Mobile Communication. arXiv preprint arXiv:0912.0758.
Chy, D. K., Khaliluzzaman, M., & Faruque, M. F. (2015). Performance Analysis of Digital Communication Systems in Presence of AWGN Implementing Filter. International Journal of Computer Applications, 975, 8887.
Cubukcu, E. (2012). Root raised cosine (RRC) filters and pulse shaping in communication systems. In AIAA Conference (No. JSC-CN-26387).
Kang, A. S., & Sharma, V. (2011). Pulse shape filtering in wireless communication-a critical analysis. International Journal of Advanced Computer Science and Applications, 2(3).
Kobra, M. J., Nakib, A. M., & Rahman, M. O. (2025). Advanced underwater image restoration: A comparative study of white balance, dehazing, and contrast enhancement techniques. Engineering Science & Technology Journal, 6(4), 201-215.
Kobra, M. J., Nakib, A. M., Mweetwa, P., & Rahman, M. O. (2025). Effectiveness of Fourier, Wiener, Bilateral, and CLAHE Denoising Methods for CT Scan Image Noise Reduction. Scientific Journal of Engineering Research, 1(3), 96-108.
Kobra, M. J., Rahman, M. O., & Nakib, A. M. (2025). A Novel Hybrid Framework for Noise Estimation in High-Texture Images using Markov, MLE, and CNN Approaches. Scientific Journal of Engineering Research, 1(2), 54-63.
Kour, G., Mehra, R., & Singh, M. (2015). Bit error rate analysis of square root raised cosine pulse shaping filter. International Journal of Engineering Trends and Technology, 28(4).
Mohammed, J. K., Hameed, S. M., & Mansoor, R. (2025). UWOC performance based on dual polarization and raised cosine filter. Journal of Optical Communications, (0).
Rana, M. M., Kim, J., & Cho, W. K. (2010). Papr reduction technique for lte sc-fdma systems using root-raised cosine filter. IJCSIS) International Journal of computer Science and Information Security, 8(6), 66-71.
Rana, P., & Mehra, R. (2015). Design analysis of channel filter for digital down converter in WiMAX application. International Journal of Computer Applications, 975, 8887.
Saad, M., Palicot, J., Bader, F., Al Ghouwayel, A. C., & Hijazi, H. (2020). A novel index modulation dimension based on filter domain: Filter shapes index modulation. IEEE Transactions on Communications, 69(3), 1445-1461.
Tepekule, B., Pusane, A. E., Yilmaz, H. B., Chae, C. B., & Tugcu, T. (2015). ISI mitigation techniques in molecular communication. IEEE Transactions on Molecular, Biological, and Multi-Scale Communications, 1(2), 202-216.
Tian, X., Wang, Z., & Huang, Q. (2023). Chaotic pulse-shaping filter based on root-raised-cosine division. Entropy, 25(1), 136.
