## 1 Introduction  
Chaos signals, which are characterized by wide continuous spectra, easy generation, and randomness, can be used as a low-cost carrier for spread-spectrum communication. Systems based on chaos, where information is embedded into chaotic signals, not only inherit the advantages of traditional spread-spectrum communication systems (such as low detection probability, interference resistance, and multipath mitigation) but also enhance data security [1, 2]. Chaotic digital modulation techniques are characterized by simple circuits, resistance to interception, and the ability to withstand adverse channel conditions. As a result, they have potential applications in secure communication [3, 4]. Therefore, in practical scenarios, non-coherent systems that do not require chaotic synchronization appear to be more feasible and attractive. Differential chaos shift keying (DCSK) is a non-coherent digital modulation scheme that utilizes chaos. In DCSK, half of the bit duration is dedicated to transmitting a reference chaotic signal, resulting in lower energy efficiency and data rate [5]. DCSK-based communication systems are advantageous for wireless sensor networks due to their low power consumption, low complexity, and resistance to channel distortion. Over the years, significant improvements have been made in the energy efficiency, data rate, and error performance of DCSK. A highly efficient scheme called high-efficiency DCSK (HE-DCSK) was proposed in [6]. This scheme cyclically reuses each reference sample in DCSK, thereby providing twice the data rate of traditional DCSK. The literature introduced multi-carrierDCSK (MC-DCSK) [7], which effectively enhanced the energy efficiency, data rate, and error performance. Furthermore, multi-carrier DCSK was improved in the subsequent literature [8; 9]. Another advancement is the short-reference DCSK system (SR-DCSK) proposed in [10; 11], which demonstrates improvements in data rate, energy efficiency, and error performance compared to traditional DCSK. Building on SR-DCSK, ref. [12] introduced an index modulation technique applied to the information-bearing signal, allowing for additional information bits. Based on the SR-DCSK principle, the literature [13; 14] proposes a short reference code index differential shift keying scheme (SR-DCSK with code indexing) and short reference orthogonal double-speed DCSK to enhance the security performance and transmission rate of communication systems. In [15], a novel carrier phase and code index modulation (DCSK) system was proposed, which demonstrated high transmission rates and low error rates, offering efficiency advantages. To address the low transmission rate drawback of multi-user orthogonal multi-level DCSK (MOM-DCSK) communication systems, ref. [16] introduced a new communication system based on DCSK, achieving higher transmission rates and lower error rates. In order to enhance security and mitigate eavesdropping or malicious attacks in wireless communication systems, ref. [17] designed an FH-OFDM-DCSK-assisted MIMO communication system. Additionally, refs. [18; 19] proposed a multi-user OFDM-DCSK system to reduce system integration complexity and improve spectral efficiency. Furthermore, coding technology has been utilized to further enhance DCSK in references [20; 21; 22]. To enhance the data rate and energy efficiency of DCSK systems, several improvement schemes were proposed in [23; 24; 25; 26]. This article introduces a novel non-coherent communication scheme termed reference signal scrambling transformation short reference differential chaos shift keying (RSST-SR-DCSK). The goal is to enhance the security of SR-DCSK systems. Through signal structure analysis, the design of both transmitter and receiver mechanisms was accomplished, with system performance being assessed via simulations. Results indicate that the proposed approach not only accelerates information transfer rates but also substantially increases the confidentiality of data by incorporating reference signal scrambling into the SR-DCSK system.