Given that a single UAV often experiences significant performance degradation when executing complex tasks due to limitations in endurance, payload capacity, and sensing range, UAV swarms have attracted considerable attention as a means to enhance task execution efficiency. However, as the size of UAV swarms increases, the demand for spectrum resources rises substantially. This challenge becomes especially pronounced when multiple clusters simultaneously transmit data, resulting in dynamic variations in data volume as tasks switch, which further exacerbates issues related to spectrum scarcity and interference. Consequently, optimizing spectrum resources under dynamically changing communication tasks and interference-prone environments, in order to ensure the stable and efficient operation of UAV swarms, has emerged as a critical problem that urgently needs to be addressed.

This study proposed a spectrum resource optimization algorithm for UAV swarms based on a convolutional temporal fusion network. The proposed algorithm integrated the local feature extraction capabilities of CNNs (convolutional neural networks) with the dynamic sequence modeling capabilities of LSTM (long short-term memory) networks to form a CL-Net (convolutional-temporal fusion network). Furthermore, the approach incorporated policy optimization using DDQN (Double Deep Q-Networks). Specifically, the CNN module was employed to extract useful local features from the input state space, thereby mitigating the negative impact of high-dimensional state spaces on training efficiency. The LSTM was utilized to capture long-term dependencies within temporal sequences, enhancing the retention of key interference patterns across frequency bands. These two components work synergistically and were integrated with DDQN to optimize the sequential decision-making process during Q-value estimation.

The proposed CL-Net algorithm was compared with LSTM-DDQN, DQN, and DDQN in terms of the reward curve, swarm throughput curve, spectrum collision rate curve, and power consumption per unit throughput. Across all four evaluation metrics, CL-Net demonstrates clear advantages. Specifically, CL-Net achieves the reward peak in the shortest time and maintained stability after reaching the peak, indicating both high efficiency and stability in learning the optimal policy. In terms of throughput, the proposed algorithm achieves the highest throughput values, demonstrating its effectiveness in optimizing spectrum resources and improving system throughput. With respect to spectrum collision rate, CL-Net remained stably around 0.2, which is significantly better than the other baseline algorithms. This result indicates that the proposed method can proactively avoid interfered channels and substantially reduce the probability of encountering interference, thus minimizing transmission disruption. Regarding power consumption, CL-Net achieved the lowest energy consumption among the four algorithms, showing that it can maintain higher throughput while ensuring better energy efficiency.

The proposed algorithm exhibits enhanced adaptability and flexibility for UAV swarms operating under dynamically varying communication tasks and interference. Compared with traditional approaches, it achieves superior performance in optimal policy discovery, spectrum resource utilization efficiency, and system stability.

As a cross-domain operational space spanning both traditional and non-traditional security fields, the electromagnetic space has become a strategic commanding height in global national security competition. The capability of the electromagnetic space security system is regarded as a core variable reshaping warfare patterns and determining battlefield dominance. Driven by the deep integration of cutting-edge technologies such as artificial intelligence and unmanned systems with modern warfare, warfare is evolving rapidly toward intelligence, and the electromagnetic space has been elevated from a traditional operational support domain to a critical maneuver operational domain and strategic competition space. In 2020, the revised National Defense Law of the People’s Republic of China officially defined electromagnetic space as a major emerging security domain. With full-domain penetrability, electromagnetic space integrates land, sea, air, space, and other physical operational domains and is deeply intertwined with cyberspace and other emerging security fields, forming a strategic layout of “full-domain coverage and cross-domain coordination.” Typical operations in recent local conflicts, including electronic reconnaissance and jamming, unmanned system confrontation, and electromagnetic spectrum offense and defense, have fully demonstrated that electromagnetic dominance has become a prerequisite for gaining comprehensive battlefield advantages and accomplishing operational objectives. Therefore, in-depth research on electromagnetic space security, clarifying its connotation, analyzing its development status and technical challenges, and proposing targeted development strategies are of great theoretical significance and practical value for safeguarding national electromagnetic space sovereignty, maintaining national security, and seizing commanding heights in strategic competition.

The evolution of the electromagnetic space security concept was systematically reviewed, and its “three-dimensional” leap characteristics were summarized: from equipment-level confrontation to space-domain control, from single-equipment protection to a full-domain security system, and from a supporting element to a battlefield-dominant element. Based on system theory and systems science, and supported by electromagnetic big data and intelligent computing, a multi-perspective electromagnetic space security architecture was proposed, whose connotation was elaborated from four dimensions: basic elements, value levels, practical activities, and technical foundations. The basic elements cover electromagnetic spectrum security, electromagnetic facility security, and electromagnetic activity security. The value levels are categorized into strategic security, availability security, and confidentiality security. Practical activities include electromagnetic space sensing, management and control, utilization, attack, and defense. The technical foundation is supported by electromagnetic big data and electromagnetic intelligent computing.

The development status of electromagnetic space security was systematically analyzed from four aspects: strategic planning, technological development, force layout, and practical application. Major military powers worldwide have elevated electromagnetic space security to the national security strategy level. The United States has issued a series of strategic doctrines such as the Electromagnetic Spectrum Superiority Strategy to lead global electromagnetic spectrum operations, and Russia has formulated specialized strategies to strengthen its electromagnetic space combat capabilities. Technically, electromagnetic space security technologies have formed five major directions: sensing, management and control, utilization, attack, and defense, featuring intelligence, systematization, distribution, and cross-domain integration. Breakthroughs have been achieved in cutting-edge fields including cognitive electronic warfare, high-power microwave weapons, and quantum sensing. In terms of force layout, the United States and Russia have established large-scale professional electromagnetic space combat force systems equipped with advanced electromagnetic warfare equipment. In practical applications, electromagnetic space security capabilities have been fully validated in recent local conflicts, playing a key role in battlefield dominance and operational system support.

The major technical challenges facing the current development of electromagnetic space security were systematically dissected. For electromagnetic space sensing, bottlenecks include difficulties in full-dimensional coverage, weak-signal detection, and real-time processing. For electromagnetic space management and control, prominent problems include intense international spectrum competition, insufficient cross-domain collaboration, and poor dynamic adaptability. For electromagnetic space utilization, constraints included the exhaustion of medium- and low-frequency spectrum resources, technical barriers in high-frequency bands, and explosive demand growth in emerging scenarios. For electromagnetic space attack, it remained difficult to realize precise strikes and balance concealment with controllability. For electromagnetic space defense, shortcomings included insufficient active defense, weak system-level protection, and the vulnerability of civil facilities.

To address the above challenges, several countermeasures and suggestions are proposed for the development of the electromagnetic space security technology system. Firstly, consolidate the fundamental theories of electromagnetic space security and conduct in-depth research on cutting-edge theories such as cognitive electromagnetism and quantum electromagnetic sensing. Secondly, break through key core technical bottlenecks to enhance the independent controllability of critical technologies. Thirdly, foster innovation-driven development momentum, advance cross-disciplinary integration, and strengthen the cultivation of professional talents. Fourthly, accelerate the practical application and deployment of electromagnetic space security technologies and improve the efficiency of technology transfer. Finally, establish a sound supporting system for the development of electromagnetic space security and optimize technical standards and infrastructure.

Electromagnetic space represents an important emerging operational domain amid the evolution of informationized warfare and major-power competition. Its security capability is directly linked to the fundamental foundations of national political stability, economic development, and national defense security. At present, electromagnetic space security is confronted with multiple challenges, including fierce competition for spectrum resources, escalating confrontation, and an unbalanced international rule system. Going forward, unmanned and intelligent technologies should be adopted to empower relevant systems. It is essential to explore the construction of intelligent electromagnetic space security training ranges, promote the application of intelligent technologies such as embodied intelligence and large models in electromagnetic space security, and continuously improve comprehensive electromagnetic space security capabilities through full-dimensional system construction, so as to build a strong safeguard for national electromagnetic space security.