文档介绍了LTE的下行物理控制信道，介绍它的处理流程以及资源映射方式。结合协议定

义，分析具体实现方式以及考量的因素。-The document describes the LTE downlink physical control channel, introduced its handling processes as well as resource mapping mode. The binding protocol definition and analysis of specific implementations, and factors to consider.