了解天线规格和操作，第2部分

　　了解天线规格和操作，第2部分

　　编者注：这两部系列的第1部分着眼于基本电磁场和天线理论，以及关键性能参数。第2部分，检查一些实际天线的性能特点，包括新的设计。

　　天线可以极大地贡献到一个系统的性能，但只有当它被给予应有的考虑，在设计过程中的早期。否则，设计者可以运行空间和形成因素的限制，将阻止天线实现其设计的潜力。

　　Also， while it’s critical that designers understand antenna theory and principles， theory can sometimes clash with harsh reality. For example， it should be recognized that specifications on an antenna’s data sheet might not be a clear indicator of its performance in the final product. This is a result of design-specific factors， as well as differing references， methods of test， and presentation formats among antenna suppliers.

　　This article will introduce popular antenna configurations such as the monopole and dipole， and discuss their performance characteristics and how to work with them in the real world. It will also discuss newer antenna designs such as patch and chip antennas， and how they can help designers meet more demanding application requirements.