Wireless module shielding cover

Structure and Principle

1. structure
   • The wireless module shielding cover is usually a metal cover, and its shape and size are customized according to the size and shape of the wireless module. Generally speaking, it has a thin-walled structure to provide shielding function while minimizing the impact on the overall volume and weight of the wireless module.
   • Common materials include copper, aluminum, and other metallic materials. Copper has good conductivity and shielding properties, but the cost is relatively high; Aluminum has slightly lower conductivity than copper, but it is lower in cost and lighter in weight, and is widely used in some cost and weight sensitive applications.
2. principle
   • Electromagnetic shielding principle: Wireless modules emit and receive electromagnetic waves during operation. The shielding cover blocks external electromagnetic interference (EMI) from entering the interior of the shielding cover through reflection and absorption, which affects the normal operation of the wireless module. At the same time, it also prevents the electromagnetic radiation generated by the wireless module from leaking out and causing interference to other electronic devices around it.
   • When external electromagnetic waves reach the surface of the shielding cover, due to the conductivity of the metal shielding cover, the electromagnetic waves will generate induced currents on its surface. According to Lenz's law, this induced current will generate a magnetic field opposite to the incident electromagnetic wave, reflecting a portion of the electromagnetic wave. At the same time, electrons inside the metal shielding cover will move under the action of induced current, and in this process, the energy of electromagnetic waves will be partially absorbed and converted into heat energy, thereby achieving shielding of electromagnetic waves.

Function and Function

1. Anti electromagnetic interference (EMI)
   • In complex electronic device environments, there are various sources of electromagnetic interference, such as radio frequency signals from other electronic devices and electromagnetic noise from power lines. The wireless module shielding cover can effectively reduce the impact of external interference on the wireless module, ensuring that the wireless module can receive and transmit signals stably and accurately. For example, in a mobile phone, multiple electronic components and modules are densely arranged, and wireless communication modules (such as Bluetooth, Wi Fi modules, etc.) are easily susceptible to electromagnetic interference from other components (such as processors, screens, etc.) without shielding protection, resulting in decreased communication quality, such as signal interruption, reduced transmission rate, and other issues.
2. Prevent electromagnetic radiation leakage
   • For some application scenarios that require strict control of electromagnetic radiation, such as medical equipment, aerospace equipment, etc., wireless module shielding covers can prevent electromagnetic radiation generated by wireless modules from leaking into the surrounding environment. In medical devices, such as pacemakers, which are highly sensitive to electromagnetic environments, if the electromagnetic radiation leakage from nearby wireless modules is too large, it may interfere with the normal operation of pacemakers and pose a threat to the safety of patients' lives. In aerospace equipment, strict control of electromagnetic radiation leakage is also to ensure electromagnetic compatibility between various electronic devices on the aircraft and avoid interference with ground communication.
3. Protect internal components
   • In addition to its electromagnetic function, the shielding cover can also provide physical protection for the components inside the wireless module. It can prevent impurities such as dust and moisture from entering the interior of the wireless module, thereby extending the service life of the wireless module. For example, in industrial environments, there are a large number of dust particles. Without the protection of shielding covers, these dust particles may adhere to the circuit board of wireless modules, causing short circuits or affecting the heat dissipation performance of components.

application area

1. In the field of consumer electronics
   • Wireless module shielding covers are widely used in devices such as smartphones, tablets, and laptops. For example, Wi Fi modules, Bluetooth modules, NFC modules, etc. in mobile phones are all equipped with shielding covers. These devices have compact internal spaces and various electronic components are close to each other. The use of shielding covers can ensure the normal operation of each module, improve the overall performance and user experience of the devices.
2. Internet of Things (IoT) devices
   • IoT devices typically include various wireless communication modules, such as ZigBee LoRa、 Bluetooth and other modules are used to achieve interconnectivity between devices. Due to the fact that IoT devices may operate in various complex electromagnetic environments, such as near home appliances in smart home environments and large motors in industrial IoT environments, wireless module shielding covers are crucial for ensuring stable communication of IoT devices.
3. Automotive electronics field
   • In modern cars, a large number of wireless modules are equipped, such as in car Bluetooth for hands-free calling and music playback, and in car Wi Fi modules for providing in car network connectivity. The electronic environment inside a car is quite complex, as the engine and other electronic control systems can generate electromagnetic interference. The wireless module shielding cover can protect the wireless modules inside the car from these interferences, while also preventing the electromagnetic radiation of the wireless modules from affecting other electronic systems in the car.
4. Industrial control field
   • In industrial automation control systems, there are a large number of wireless sensors and wireless communication modules used to monitor and control the operating status of industrial equipment. In industrial environments, there are often strong electromagnetic interference sources such as high-power motors and transformers. The shielding cover of wireless modules can ensure the reliable operation of wireless sensors and communication modules in such harsh electromagnetic environments.