In China, the mobile phone industry has emerged from scratch. Mobile phone design has developed from mature purchase scheme to independent design scheme. In a short period of 3-4 years, the mobile phone industry in China has developed to its pre-eminent prosperity. With the rise of many mobile phone manufacturers, the mobile phone industry-related supporting manufacturers gather in the concentrated areas of the industry. Set, in recent years, mobile phone antenna suppliers with rapid development are expanding with cellular development. On the one hand, it greatly shortens the design and production cycle of mobile phone antenna, facilitates the rapid implementation of trial production and mass production for mobile phone design and production enterprises, on the other hand, it accelerates the adverse competition in the mobile phone antenna industry, and weakens the mobile phone. The technical content of antenna design greatly reduces the quality of products and the future development of antenna.

In mobile phones, antenna directly affects the communication ability of mobile phones, directly determines the radio and reception performance of mobile phones, and even determines the survival space of mobile phones in the market. Overseas, brand mobile phone design manufacturers generally pay more attention to antenna research and development and design in the early stage. They mostly cultivate one-day antenna design and production institute or professional small antenna design company in the form of equity participation and holding. NOKIA controls Feichang in China, MOTOROLA shares in the domestic market and pays more profits. In this environment, specialist Industry antenna design companies provide enough antenna design support for large brands of mobile phones. So well-known brands such as NOKIA, MOTOROLA, SUNSUNG can always design antenna with excellent performance in a specific environment, and integrate the ID of mobile phone with the first-class function. At present, only a few large companies pay more attention to the design and manufacture of antenna in domestic mobile phones. Most small and medium-sized enterprises only regard antenna as common hardware, compress and compress in space, and perform poorly and poorly. The ultimate result is that customers or end-users of mobile phones can not accept the "callable" of mobile phones. ” Performance leads to the abortion or redesign of the project, the waste of resources and human resources and the loss of business opportunities, which greatly reduces the comprehensive competitiveness of enterprises.
Professional analysis shows that the antenna performance is affected by the following factors:

space
There is a motto in the industry that "how much space determines how much performance", and enough practicable space is necessary for antennas. As for the design space of antenna, it is suggested that customers should communicate with antenna design engineers in depth in the early stage of scheme design to understand the layout of antenna and potential problems, so as to reserve the position. Antenna engineers have considerable design experience in the design process, which layouts are beneficial to the design of antennas, and which spaces have a greater improvement in the performance of antennas. It is necessary to define a new scheme. At the same time, it is more conducive to the rational allocation of antenna space and more complete allocation of antenna space by referring to the suggestions of several antenna design companies.

As for the available space of antenna, antenna design companies and mobile phone manufacturers often meet the basic requirements of antenna space in order to improve antenna performance and strive for antenna space layout. Only a few design companies will meet the basic requirements of antenna space, while most design companies will compress the antenna space as much as possible in the name of complete and functional mobile phones. Antenna space, the consequence is that a single case will frequently change the antenna design company, the result is that the antenna performance can not meet certain requirements, the case abortion, hate the ability of antenna design company is too poor, and so on. We all know that today's mobile phone antenna is the evolution of dipole antenna, antenna can not achieve functions in infinite space, antenna must need a relatively open and broad space, so to speak, no one can complete the "mobile phone antenna zero space" topic.

EMI
EMI (Electro Magnetic Interference) is a common problem in the electronic industry. Many of the problems are due to the poor implementation or in-depth consideration of the related processing. In the initial stage of mobile phone antenna transition from external antenna to built-in antenna, many mobile phone design companies generally encounter the problem of mobile phone dynamic reception sensitivity. The schematic diagram may be consistent with the schematic diagram of PCB of the former external antenna, but the built-in antenna encounters the problem of sensitivity, because what? At that time, most companies thought that antenna was a problem, and few people doubted that it was a problem of their own design. The problem is the mutual interference of circuit or other components on antenna radiation, which will affect the reception quality of mobile phone in the process of dynamic reception. With the reference of bit error rate, the dynamic sensitivity is low. The problem of EMI will not affect the radiation power of the antenna, and it will not affect the radiation efficiency of the antenna, but there are great hidden dangers to the receiving performance of the antenna, so it is necessary to do well the EMI processing of the circuit for the comprehensive performance of the antenna. Through reasonable grounding processing and circuit compatibility processing and so on.

As for the 3G mobile phone, which will be widely launched in the near future, it needs better antenna, high specifications and high efficiency requirements, especially the impact on human body must be reduced. In the past, GSM mobile phones used the technology of TDMA, and only 1/8 of them had signals with time. However, in the era of 3G, when adopting the technology of CDMA, for continuous modulation, the impact on the human body is relatively large. Therefore, the antenna of mobile phones has stricter requirements. High specifications, anti-jamming ability is very important, noise suppression ability is not enough is the key, if the noise can not be filtered out, anti-jamming tolerance is enough is the key.  Mobile phone manufacturer's experience is very important. If the experience is insufficient, the parts should be positioned.