The whole problem with stray RF modules

The whole problem with stray RF modules between the antenna and the resonant matching circuit, and if the stability of the resonant circuit is a bad match, it is easy to excite high-order harmonic interference. As the mobile phone antenna in the neighborhood of the media more sensitive, so the shell is closely related to the design and performance of the antenna. Shell surface of the coating material can not contain metal components, housing close to the antenna not designed around any decorative pieces or metal plating. If necessary, should be used to achieve non-metallic process. Spray the inside of the conductive housing, the antenna should be limited to 20mm away from the office. For pure metal battery cover, should be more than 20mm from the antenna. The detecting network can be formed in the area to be shielded through the specific network mode of phone jammer intelligent management system.
Such as the use of unipolar (monopole) antenna, panel and disable the metal shell circular metal decoration. Battery (electric connection base) and the antenna should be designed in more than 5mm. Radiator area of 550 ~ 600mm2, with the main PCB TOP surface distance (height) 6 ~ 7mm. Antenna and the motherboard has two feed points, one antenna module output, the other is the RF ground. Position in the top of the phone antenna. PIFA antenna such as the law required skin design environment structure, quite excellent electrical properties, including the SAR indicator, built-in antenna is preferred. For a certain thickness of the mobile phones, folding, sliding, capping, straight machine. Antenna within the projection area complete paving, and do not arrange the antenna side components, especially motors, SPEAKER, RECEIVER, FPC cable, LDO and other large metal structure of the low-frequency driver components and devices. Their electrical performance of the antenna have a significant negative impact the proposed design is generally in the top left or top right; 4 ~ 5mm spacing in between. phone jammer can make sure that environment can be purified and secrecy leaking and crimes can be prevented.
Antenna from the plastic bracket and metal (radiator) composition. Metal and plastic stent fixed using hot-melt method. ABS or PC material commonly used in plastic, metal commonly used beryllium copper, phosphor bronze, stainless steel sheet. Can also be FPC, but the motherboard to add two PIN, both the higher cost.