- مبلغ: ۸۶,۰۰۰ تومان
- مبلغ: ۹۱,۰۰۰ تومان
Channel coding and security are important in a communication system. The 5th generation (5G) mobile communication networks call for higher requirements of new coding technologies and encryption technologies. As an efficient coding method, polar codes have attracted more attention in recent years. Besides, the peak-to-average-power ratio (PAPR) is a major problem of the orthogonal frequency-division multiplexing (OFDM) system, which will significantly affect the performance of the OFDM system. In this paper, joint physical-layer encryption and PAPR reduction scheme is proposed, aiming to solve the PAPR problem and achieve high security of the transmission system. In this scheme, we utilize the key generation technology of wireless channels to get the initial value of chaotic sequences. Then, the chaotic sequences can be used to encrypt the information and reduce PAPR simultaneously. Moreover, we use the best information bits of polar codes to store the serial number index of chaotic sequences. The theoretic analysis and simulation results show that the proposed scheme can not only achieve high security in the physical layer but also reduce PAPR in the OFDM system without increasing system complexity and latency.
With the rapid development of wireless communication technology, 5G has become a research hotspot in the field of wireless communication. 5G will meet diverse business needs of work, life and entertainment. In addition, 5G will penetrate into all fields of industry to effectively meet the diversified business needs and realize the interconnection of all things such as industries, medical cares and transportations. The key technologies of 5G mobile communication are mainly embodied in ultra-efficient wireless transmission technology and high-density wireless network technology . Channel coding technology with high performance and efficiency is also an important research direction of 5G. In 1948, Shannon proposed the mathematical theory of communication . In 1962, Gallager proposed low-density parity-check (LDPC) codes . In 1992, C. Berrou et al. of France proposed the revolutionary Turbo codes . However, neither the Turbo code nor the LDPC had been theoretically proved to be able to reach the Shannon channel capacity. Professor Arikan first proposed the concept of polar codes, which rigorously proved that polar codes can reach the channel capacity in binary discrete memoryless channels (B.DMCs) . In 2016, polar codes scheme became the final solution for enhanced mobile broadband (eMBB) scene of the 5G control channel, and successfully entered the 5G basic communication framework protocol . In 2018, the 5G system that meets the 3GPP standard and supports polar codes was officially released.
In this paper, the reduction of PAPR in OFDM system is combined well with the encryption using the coding characteristic of polar codes. Based on the characteristics of wireless channels, chaotic sequences are provided for encryption. Inspired by the idea of SLM, chaotic sequences are utilized for PAPR reduction and the system model is simplified. Moreover, side information containing the bits of serial number indices is conveyed by the largest channel capacity of polar code, leading to the improvement of BER performance. Therefore, the proposed scheme can both effectively reduce the PAPR of the OFDM system and realize encryption in the coding process, which enhances the security and reliability of the system.
در این مقاله، کاهش PAPR در سیستم OFDM با رمزنگاری مبتنی بر مشخصه کدگذاری کدهای قطبی، ترکیب شده است. بر اساس ویژگیهایی که کانالهای بیسیم دارند، برای رمزنگاری از دنبالههای آشوبی استفاده شد. با الهام از ایدهی SLM، دنبالههای آشوبی برای کاهش PAPR به کار رفت و مدل سیستم نیز ساده شد. همچنین اطلاعات جانبی مربوط به شاخص شماره سریال توسط کانالی که دارای بیشترین ظرفیت و کدگذاری قطبی بود، انتقال داده شد که این امر باعث بهبود عملکرد BER شد. بنابراین طرح پیشنهادی میتواند PAPR را به طور موثر از سیستم OFDM کاهش داده و رمزنگاری را در فرآیند کدگذاری محقق کند که امنیت و قابلیت اطمینان سیستم را افزایش میدهد.