说明：  一共四本书，都是华为培训员工的资料。书名分别是《硬件工程师手册》，《印制电路板（PCB）设计规范》，《射频基础知识培训（华为）》，《华为通信基础培训教程》。很有参考价值！
(A total of four books, all Huawei staff training information. Title are the " hardware engineer Manual" , " Printed Circuit Board (PCB) design specifications" , " RF Fundamentals Training (Huawei)" , " Huawei Communication Foundation training course." A good reference!)