TECHSHIP IS A GLOBAL SUPPLIER OF WIRELESS COMPONENTS
The EM820U module works inside the portable computer through the Mini PCI-E interface, which is inconvenient for the user during measurement and commission. With the EM820U simplified board, the signals that the EM820U module needs on the Mini PCI-E interface are simulated outside the portable computer. The signals are used for product development, commission, and software upgrade on production lines.
This document describes the AT interface of Huawei EM820U Datacard/Modem. The description on the AT interface is only limited to the interface packet itself. The usage and use procedure of TE and MS do not cover the contents which are not directly related to the interface.
This document describes the hardware application interfaces and air interfaces that are provided when the Huawei EM820U HSPA+ PC Embedded module (hereinafter referred to as the EM820U module) is used.
This document helps you to understand the interface specifications, electrical features, and related product information of the EM820U module. To facilitate its use in different fields, relevant development guides document are also provided with the module, which can be obtained through Huawei website.
This document describes the methods of inspecting Huawei's shipments of WCDMA modules. Customers can refer to this document when formulating inspection guides for accepting Huawei's WCDMA modules.￼￼￼
This guide is applicable to the acceptance inspection of Huawei's MU509 and EM820W modules. The inspection methods provided in this guide are recommendations, which can be modified by customers if necessary.
In the design of Huawei's modules, the impedance of both the antenna interfaces and external antenna switch connectors is designed to be 50 ohm. However, in actual production, it is difficult to make the impedance to be exactly 50 ohm. In this case, to obtain optimum radio frequency (RF) performance, a conjugate impedance match between an antenna interface and an external antenna switch connector is needed. Therefore, an impedance matching network is added between an external antenna and a module's antenna interface, to avoid impedance mismatch in the RF channel that causes reflection, power consumption, and consequently deteriorated RF performance.
This design guide describes design and tuning methods for the impedance matching of RF antenna interfaces.
The specific absorption rate (SAR) is the electromagnetic energy absorption rate of wireless products, for example, mobile phones. The SAR typifies the electromagnetic power that is absorbed or consumed by a unit mass in human tissues. The international scientific community uses the SAR to quantize and measure the mobile phone radiation. The higher the SAR value of a mobile phone is, the more the mobile phone affects the human body.
The transmitting power is directly proportional to the SAR value. The larger the transmitting power, the higher the SAR value.
The module product provides a BODYSAR function, which uses relevant AT command interfaces to dynamically limit the maximum transmitting power of a module and accordingly limit the SAR value.
This document describes the interfaces of the AT commands related to the BODYSAR function and the common usages and processes of these interfaces.
This document provides information about the audio interface design and tuning suggestions for Huawei modules. This guide is applicable to the Huawei modules that provide audio functions.
From this document, you can learn the specifications, product information and tuning experience for using Huawei modules.