Traditional in-vehicle smart devices, especially in agriculture and construction equipment, typically operate in complex and harsh environments. As a result, many manufacturers focus their design and development efforts on improving device reliability, such as a wide voltage input range, a more efficient heat dissipation system, a more reliable waterproof and dustproof design, etc. The mobile performance of the device is often overlooked. At the same time, these reliability designs also increase the difficulty of designing a highly efficient antenna.
Challenges in developing conventional antennas for in-vehicle devices?
The design of intelligent vehicle hardware with wide voltage input leads to a large number of circuits for power conversion in the device. During the operation of the DCDC circuit, the inductor is charged and discharged at high frequency, and the inductor and capacitor have parasitic effects that cause ringing. The peak of ringing is too high, which means there is a strong current change at high frequency, causing EMI problems and disturbing low-frequency signals;
The intelligent hardware installed in the vehicle uses vehicle-grade electronic materials and modules, the integration is relatively low, and there are many customized functions and modules. The modules are transmitted through standard protocols such as USB3.0, SDIO3.0, MIPI, and LVDS. Such high-speed signals generate noise signals that seriously interfere with low-frequency signals;
Intelligent hardware in the vehicle has a very extensive interface, such as GNSS antenna, power supply output, RS485 and camera interface, etc., resulting in a relatively complex internal cycloid, compact space, and slight crosstalk with each other, causing low-frequency signals to be disturbed;
The low-frequency signals of in-vehicle smart devices are limited by the above factors, and the sensitivity is much lower than that of the 3GPP standard. However, the usage scenarios of equipment mounted in agricultural vehicles are basically low frequency. Usually, operators in agricultural areas with large areas and sparsely populated areas use low-frequency solutions, which can exponentially reduce the number of base stations and improve efficiency. Therefore, devices with poor low-frequency signals will occur in large areas. The signal status has a significant impact on the function of the in-vehicle smart product.
In response to the above problems such as electromagnetic EMI and crosstalk, CP's Spring 2 series is equipped with Ultra-Link wireless signal transmission technology. This technology relies on the built-in antenna developed by CP to optimize and improve the OTA performance of the antenna: ① Fully evaluate and optimize the structure in the early phase stacking space, reduce the interference source around the antenna and improve the free space, so that the average efficiency can reach more than 30%; ② Reduce the desense as much as possible, so that the average is less than 3dbm, for the DCDC ringing EMI problem, the scatter high-speed signal line, peripheral interface and other interference, respectively, adjust targeted structural stacking standards, PCB wiring rules, and strictly enforce.
The test data shows that the Spring 2 equipped with the Ultra-Link design solution has obvious advantages over consumer products (the average design solution of consumer products in a similar low-density base station environment is used as a comparative value).
OTA Active Comparison Data of Apartment Spring 2 and Similar RF Design Consumer Products at Low Frequency
The application of the ultra-sensitive Ultra-Link wireless signal transmission technology in Spring 2 can ensure that devices in low-density areas with weak signal coverage can receive high-quality communication signals, greatly improving the user experience in remote areas with a sparse population. 4G Signal Intermittent Problem.
