The UAE's SkyShield anti drone electronic warfare system. An FPV drone is rapidly approaching the enemy's active area, about to enter the first line of defense of the enemy's position. At this moment, the FPV drone suddenly lost control and plunged into the ground like a broken kite. This kind of scene is not uncommon in armed conflicts in some hotspot areas at present. Apart from its own sudden malfunction, an FPV drone that has not suffered significant damage and suddenly lost control is likely to have been "shot down" by the opponent's portable anti drone electronic warfare system. What is a portable anti drone electronic warfare system? Why did it appear on the battlefield and develop rapidly? What are the characteristics of portable anti drone electronic warfare systems currently being developed by various countries? What are the future development prospects? Please refer to the interpretation in this issue. In response to the rapid development of the "simplified version" of drones, according to foreign media reports, the US Army is currently exploring the potential of a backpack electronic warfare system called TLS-BCT, which was issued to soldiers in August this year. One direction is to use it to better identify incoming drones. The reason for this move is twofold: on one hand, it is due to the potential of this backpack electronic warfare system, and on the other hand, it is because the US military recognizes the serious threat posed by current drones, especially the "simplified version" drones. In fact, not only the US military, but many countries have begun to pay attention to the impact and changes brought by the "simplified version" of drones. Currently, the "simplified version" of drones is widely used in armed conflicts in hotspot areas. Its cost is relatively low and command and control is not complicated, but the achievements are significant and the threat is great. The deployment of FPV drones on the battlefield further highlights this threat, quickly becoming a "ghost killer" active on the battlefield with fast flight, flexible positioning, and a control method similar to "human in the loop". The achievements and potential demonstrated by the "simplified version" of unmanned aerial vehicles have not only made countries pay more attention to the development and use of small and micro unmanned aerial vehicles, but also prompted them to consider how to respond to such drone threats. To counter drones, besides hard destruction, it is also soft killing. One of the main ways of soft killing is through the use of electronic warfare systems. When it comes to electronic warfare systems, many people think of Russia's "Krasuha-4" ground electronic warfare complex and its power. The Krasuha-4 can not only suppress the airborne radar signals of enemy fighter jets and interceptors, but also be used to suppress the signals of enemy drones, reconnaissance aircraft, and low orbit satellites. In February 2020, the "Krasuha-4" deployed at the Hmeimim Air Force Base directly took over control of incoming drones. However, large and medium-sized electronic warfare systems, such as "Kelasuha-4" and "Kolar" in Türkiye, are usually large and installed on one or more vehicle chassis. Their design is not intended to deal with "simple version" UAVs. The development of large and medium-sized electronic warfare systems usually revolves around the radar signals of large aircraft, and carries out strategic and combat missions. However, the "simplified version" of unmanned aerial vehicles belongs to low, slow, and small targets, with close flight distances and variable movements. Therefore, the latter approach is not only "barely feasible", but also equivalent to "using cannons to kill mosquitoes" in terms of cost-effectiveness. Moreover, large and medium-sized electronic warfare systems are bulky and difficult to conceal their movements, making it impossible to achieve the goal of catching off guard and quickly responding to the "simplified version" of drones. So people began to turn their attention to portable anti drone electronic warfare systems. On the one hand, some countries have begun to dismantle some of their existing vehicle mounted and airborne electronic warfare equipment and retrofit them into portable models. For example, Russia's portable anti drone electronic warfare system is a modification of the "Salamander" modular anti drone jamming system originally equipped on main battle tanks. On the other hand, many countries have begun to develop new portable anti drone electronic warfare systems, such as the PARASOL trench electronic warfare system launched by Ukraine in May this year. It should be emphasized that, based on different battlefield requirements, portable anti drone electronic warfare systems are also developing in different directions: some focus more on flexible deployment and have developed into portable anti drone electronic warfare systems carried by humans; Some focus on comprehensive functionality and have developed into vehicle mounted portable anti drone electronic warfare systems. Unlike vehicle mounted large and medium-sized electronic warfare systems, portable anti drone electronic warfare systems have a smaller volume and are mainly used as light tactical vehicles, or only as part of the functional configuration of some vehicles such as tanks. For example, Russia's "Breakwater" Volnorez electronic warfare system can be installed in just 10 minutes using a magnetic bracket, without the need for structural modifications to the vehicle. For many people, electronic warfare systems are a mysterious equipment with both strengths and weaknesses. Understanding the operating principle of portable anti drone electronic warfare systems can help people uncover the "mysterious veil" of electronic warfare systems. Simply put, the portable anti drone electronic warfare system's countermeasure against the "simplified version" of drones is to make efforts in controlling the electromagnetic signals of drones, finding loopholes and attacking their "weaknesses". For example, many unmanned aerial vehicles use global satellite positioning and navigation systems to determine their location. So, by interfering with the satellite positioning and navigation signals it uses, it can lose its directional guidance. For example, some drones such as FPV drones have a high dependence on wireless communication, so by blocking or interfering with wireless communication signals, they can be disconnected from the control device and unable to perform tasks. If the "simplified version" of the drone is compared to a kite, then these electromagnetic signals are like the leads that control the kite, while the portable anti drone electronic warfare system is like a "invisible scissor" that can be swung into the air at any time to cut the leads. From this, it can be seen that the electronic warfare system is actually a specialized device composed of radar antennas, jammers, and other devices for receiving, identifying, analyzing, simulating, transmitting, and transmitting electromagnetic signals. It can achieve the goal of "weakening the enemy and protecting our own side" by understanding the electromagnetic frequency band used by the opponent and "interfering with it". Compared with large and medium-sized electronic warfare systems, portable anti drone electronic warfare systems have both advantages and disadvantages. These strengths and weaknesses together constitute some of the characteristics of its current development. Firstly, it can be flexibly deployed and used at any time. For portability, some current anti drone electronic warfare systems have been almost streamlined to configurations that only include basic sensors, resulting in smaller sizes and lighter weights. Many countries have developed anti unmanned machine guns that weigh no more than 10 kilograms, including jamming aircraft and directional antennas. They can be carried in a backpack in the shape of a rifle, and some even have a handgun shape, making them more portable. The K-1000 FPV unmanned aerial vehicle "Dome" suppression electronic warfare system developed by Russia weighs only a few kilograms and is easy to carry and install. Some countries have equipped their armies with backpack style electronic warfare systems. Generally speaking, these portable anti drone electronic warfare systems can generate high-energy electric or magnetic fields in a short period of time, suppressing the signals used by some drones' operating frequency bands, including their satellite positioning and navigation devices. The Burdock portable anti drone electronic warfare system from Russia can emit narrow beam radar waves, detect targets with a radar reflection cross-section of 0.01 square meters, and have a maximum detection range of 10 kilometers for ultra small airborne targets. It can also simultaneously detect multiple targets and provide their location data information. Secondly, most of the functions are relatively single, and the interference frequency band is relatively fixed. In order to achieve portability, most current anti drone electronic warfare systems focus on functionality, with some emphasizing electronic attacks, some emphasizing electronic support, and some emphasizing electronic protection, aiming to reduce weight by focusing on "attacking one point and being inferior to others". The portable drone detector developed by Australian company DroneShield weighs 700 grams and can be used to monitor enemy drones invading within 1 kilometer and issue alerts. The SkyShield anti drone electronic warfare system launched by EDGE in the United Arab Emirates, even if it is a vehicle mounted equipment, can only be used for electronic attacks and currently does not have the ability to locate and track drones. Of course, there is no absolute solution, and not all portable anti drone electronic warfare systems have a single function, which is mainly related to the integration level of the research and development countries. The AUDS "anti drone defense system" developed by the UK is an anti drone system that integrates detection, tracking, and jamming functions. It can respond to target drones within a range of 8 kilometers and even take over their control. The third is to have partial security interference capability to ensure better achievement of goals. Some current vehicle mounted portable anti drone electronic warfare systems can be remotely controlled and can interfere with the opponent's electromagnetic signals without affecting the use of our own electromagnetic equipment, thus possessing partial safety interference capabilities. Some research and development manufacturers have begun to broaden the detection methods of drones, making electronic warfare systems more covert and secure during operation. For example, Australia's DroneShield company's "anti drone electromagnetic gun" DroneGun Tactical uses acoustic sensing devices to capture the noise generated by drones and locate them. This method does not emit radio frequency to the outside, making it difficult to detect. Some are seeking breakthroughs in their usage, such as the PARASOL trench electronic warfare system developed by Ukraine, which has two different variants: one is to counter the opponent's drones, and the other is to protect their own electronic signals from interference, thus giving the system a certain level of stealth capability. Some portable anti drone electronic warfare systems in vehicles are empowered by new technologies, including the use of narrow beams or low-power transmission, as well as the use of anti-interference advanced waveforms, in order to "control people but not people". In addition, the current portable anti drone electronic warfare system also has some other characteristics, such as the main energy sources being lithium batteries, car power, and grid power. The Burdock portable anti drone electronic warfare system from Russia has three power supply modes, with a total weight of 25.5 kilograms. It can run continuously for 8 hours with the radar's built-in power supply and can also obtain power from the public power grid or car power supply. The biggest advantage of portable anti drone electronic warfare systems, which may work hand in hand with other anti drone means, is that they transform electronic warfare from strategic and campaign actions into flexible and active tactical actions at the forefront of confrontation, providing effective methods for dealing with "simplified versions" of drones. However, overall, the development of such electronic warfare systems is still in its early stages and may move towards the following areas in the future. Firstly, it has become more compact, portable, and practical. Whether carried by humans or vehicles, portable anti drone electronic warfare systems will develop towards greater portability and become more versatile with the high integration of functional units. Only then will these anti drone electronic warfare systems become more user-friendly. In addition, open architecture may become the design concept for such electronic warfare systems. In this way, such electronic warfare systems can effectively respond to changes in drones through timely empowerment, become a weapon against drones, and even become a part of individual equipment systems. Secondly, constantly updating and upgrading towards intelligence. With the rapid development of electromagnetic spectrum technology, the electromagnetic signals used by some drones can undergo rapid changes. The emergence of drone swarms and their ability to carry electronic warfare systems pose new challenges for countering drones.