SNOW-3G and ZUC are two stream ciphers standardized by the 3GPP (3rd Generation Partnership Project) organization to ensure the LTE (Long Term Evolution of radio networks) security. Unfortunately, these algorithms present some weaknesses. The main objective of this study is to design and implement an enhanced algorithm combining the functionalities of standard SNOW-3G and ZUC algorithms in order to provide security to the LTE network. A chaotic generator has been used to increase the randomness and robustness of generated key-streams. The proposed architecture was implemented on Xilinx virtex-S FPGA technology and its security was evaluated using many security tests (generated key-stream distribution, key sensitivity, key space, and NIST statistical tests). The experimental results show that the proposed design allows to encrypt data in two operating modes (SNOW-3G and ZUC modes) using limited hardware resources and power consumption while ensuring more resistance against cryptanalysis attacks.