了解天線規(guī)格和操作

? ? 　本文是由兩部分組成的系列的第1部分。它將介紹設(shè)計(jì)師天線的理論，規(guī)格，天線設(shè)計(jì)的趨勢(shì)，以及現(xiàn)實(shí)世界的天線的例子。第2部分，將深入探討最新的天線設(shè)計(jì)，以及如何指定和應(yīng)用它們。

　　天線可能是最受忽視的RF設(shè)計(jì)的一部分，但范圍，性能和合法性的RF鏈路是非常依賴于它。無(wú)論如何，天線的選擇往往是直到設(shè)計(jì)結(jié)束時(shí)，在該點(diǎn)的最佳天線性能可能無(wú)法實(shí)現(xiàn)的空間內(nèi)提供。

　　在這一點(diǎn)上的選擇可能要經(jīng)過(guò)多個(gè)設(shè)計(jì)或最終接受的降解性能。這兩個(gè)選項(xiàng)是可取的，但與各種類型的天線的理論和行為的基本理解，可以避免的情況下，一個(gè)設(shè)計(jì)師可以得到更接近最佳的RF性能。

　　To that end， Part 1 of this two-part series focuses on the basic electromagnetic field principles of antennas. It then illustrates these principles with two styles of antennas that are often used in low-power handheld products： dipoles and monopole whips. These types cover a wide range of available antennas and are among the most common to be implemented incorrectly. （For more on antenna selection， see the TechZone article， “Antenna Selection Depends on Many Factors”。）

　　Part 2 of the series looks at dipole and monopole antennas in more detail， while also discussing some antenna design trends that are being driven by the needs of today‘s wearable， handheld， and compact devices. These newer antennas include chip antennas such as theJohanson Technology 2450AT18B100E， 2.4 GHz to 2.5 GHz chip RF antenna， and patch antennas such as the Antenova SRF2W012-100 DROMUS， flexible dual-band Wi-Fi antenna. It will also discuss antennas fabricated as part of the pc board itself.