Unmanned aerial vehicle (UAV) swarms, characterized by high mobility, low cost, flexible deployment, and distributed coordination, demonstrate disruptive potential and broad application prospects across military (e.g., reconnaissance, electronic warfare) and civilian domains (e.g., disaster rescue, environmental monitoring, smart cities). The core enabler for UAV swarms to function as a cohesive unit and unleash their systemic effectiveness lies in efficient communication and networking technologies. However, the inherent attributes of UAV swarms—highly dynamic and resource-constrained—combined with the complexity and adversarial nature of their operational environments, pose unique challenges: High-dynamic flight leads to spatio-temporal-frequency non-stationary channels and volatile topology changes, invalidating traditional quasi-stationary channel assumptions; Severe on-board resource constraints (energy, computation) create conflicts between physical-layer energy scheduling and network-layer routing overhead, highlighting bottlenecks in cross-layer optimization efficiency; As a typical cyber-physical system (CPS), communication delay directly impacts control loop stability, yet the deep coupling mechanisms among communication, computation, and control (C3) remain unclear, making task-driven dynamic resource adaptation difficult. Furthermore, demands for large-scale reliable networking, real-time high-speed transmission, intelligent communication, robust anti-jamming capabilities, cost-effectiveness, and evolutionary development, coupled with new requirements driven by 6G-enabled low-altitude economy applications (e.g., integrated sensing and communication (ISAC), ubiquitous coverage, deterministic networking, intrinsic security), underscore communication and networking technologies for UAV swarms as a critical and urgent field for breakthroughs, holding significant research importance and practical value.

Significant progress has been made in UAV swarm communication and networking, reflected in layered technological systems and intelligent empowerment:

• Physical layer transmission: Addressing high-dynamic channels, research focuses on novel waveforms. Orthogonal frequency division multiplexing (OFDM) is widely used for its multipath resistance and compatibility with MIMO, but suffers from high peak-to-average power ratio (PAPR) and out-of-band emission (OOBE) limitations under high Doppler. Orthogonal time frequency space (OTFS) modulation, operating in the delay-Doppler domain, effectively combats time-frequency doubly dispersive channels, though high detection complexity remains a challenge. Low-complexity detection algorithms (e.g., optimized Message Passing) and integration with non-orthogonal multiple access (NOMA) are key research areas. Affine frequency division multiplexing (AFDM), compatible with OFDM through parameter tuning and achieving full diversity in linear time-varying channels, attracts interest for its lower complexity demodulation. Integrated control and data transmission waveforms (e.g., DSSS based on SC-FDE) are designed to meet diverse service needs. ISAC waveforms (e.g.,, OTFS/AFDM) leverage channel characteristics for environmental parameter sensing without extra hardware, with optimization schemes for UAV coordination being a frontier. Anti-jamming techniques encompass waveform-level approaches (DSSS, FHSS, burst communication) and suppression techniques in frequency/time/space domains (e.g., millimeter-wave (mmWave) directional communication). MmWave, with its vast bandwidth and narrow beams, offers great potential for anti-jamming and high data rates, but requires solutions for robust beamforming and rapid node discovery.

• Data link and network layer technologies: To tackle high-dynamic topology, research concentrates on hybrid communication (omnidirectional/directional), efficient medium access control (MAC) protocol design, multi-dimensional resource (power, spectrum, trajectory) optimization scheduling, high-dynamic routing protocols, and heterogeneous swarm networking. Hybrid communication combines omnidirectional neighbor discovery with directional anti-jamming. Resource scheduling aims to resolve competition in large-scale networking. Routing protocols must adapt to 3D high-speed mobility for low-latency reliable transmission.

• Communication, computing and control fusion and joint optimization: Recognizing UAV swarms as CPS, this research explored the mapping between communication delay, computational load, and control precision (e.g., formation keeping, task allocation), seeking joint optimization methods for task-driven dynamic resource adaptation.

• Intelligent empowerment: An intelligent architecture integrating "Intent Understanding - Environment Adaptation - Resource Scheduling" was proposed, enabling autonomous perception, intelligent decision-making, and dynamic network reconfiguration, supporting the evolution from "mechanical linkage" to "autonomous collaboration." Intelligent collaborative schemes for lightweight and weak-connectivity environments were explored.

• Engineering applications: Focus areas include high-frequency band hardware optimization, lightweight antenna design, and modular communication chips/protocols to overcome size, weight, and power (SWAP) constraints and facilitate deployment.

• Network security: UAV swarm communication security and intelligent protection techniques were summarized to counter threats in complex electromagnetic environments.

Communication and networking technologies are pivotal for UAV swarms to achieve systemic collaborative effectiveness. This review systematically outlines the key technological challenges, research status, and development trends in this field. Current research has made significant strides in physical layer waveforms (e.g.,, OTFS/AFDM), ISAC, anti-jamming (notably mmWave), hybrid networking and resource scheduling at the data link and network layers, C3 fusion, and intelligent architectures. Looking ahead, UAV swarm communication and networking will be deeply integrated into future space-air-ground integrated networks (SAGIN):

• Network architecture: A unified, open, and scalable SAGIN architecture supporting diverse UAV roles (aerial base station, relay, terminal, and ad-hoc node) is essential.

• Key technologies: Priority areas include optimization and lightweighting of high-frequency (mmWave/THz) communication hardware, deep C3 coupling mechanisms and joint optimization frameworks, intelligent autonomous network management, and high-reliability low-latency transmission (e.g., 6G deterministic networking), and intrinsic security mechanisms.

• Intelligence trend: AI will further empower swarms, enabling more precise intent understanding, environmental perception, and resource scheduling, enhancing autonomous collaboration and survivability in complex scenarios.

• Application-driven evolution: The large-scale development of the low-altitude economy will spur new requirements for ISAC-enabled intrinsic perception, ubiquitous coverage, high-density access management, and stringent safety regulations, driving technological advancements. Future research must deepen foundational exploration (e.g., high-dynamic channel modeling, C3 coupling mechanisms), and break through core technologies (e.g.,, lightweight high-frequency hardware, intelligent resource scheduling), and strengthen standardization and engineering applications to underpin the widespread adoption of UAV swarms in future intelligent networked warfare and the low-altitude economy.