cdma射頻前端的智能集成

　　本文的目的是提出一個高度集成的三頻雙模例（CDMA GPS射頻前端解決方案）以三Avago的高度集成的RF模塊。

　　今天的移動設備相當復雜，許多射頻收音機包裝成一個不斷縮小的足跡。如何將更多的無線電組件打包成更小的空間？收縮單個無線電組件是顯而易見的，而單個部件的集成是另一個。整合的原因已經有據可查了。除了實際節省空間外，還有改進的性能和簡化的設計，從而更快地進入市場。如果這里有一個“圣杯”，它將是一個單獨的即插即用模塊，它包含了整個射頻前端，用戶可以直接進入他們的PC板。

　　這個“圣杯”的例子可以在Wi-Fi空間看到。今天，完整的雙波段802.11 A，B，G，N Wi-Fi前端存在單模塊尺寸4x6毫米的小。這些模塊包含整個射頻前端包括功率放大器（PA）、低噪聲放大器（LNA），過濾器，和單個基片上的所有開關，這是一個真正的即插即用的射頻和天線之間玩。這些模塊的采用對于今年正在設計的下一代筆記本電腦尤其強勁。

　　Integration of CDMA and UMTS RF front ends in mobile handsets is not as advanced as Wi-Fi front ends yet. One of the reasons is that the content of the UMTS RF front end is still continually varying and is region-specific. The CDMA RF front end， however， is fairly standardized in North America as dual mode， tri-band PCS and Cell band plus GPS， and integrated module solutions have the potential to be widely implemented as in the Wi-Fi case.

　　The two main paths for RF integration are by-band （combining PA and duplexer of a single band） or by-technology （combined PA modules and combined filter modules）。 Both provide the benefits of saving space and simplifying design， but the by-technology approach can also provide performance improvements through pin map optimization. Of the two choices， integration by-technology has proven to be the more common solution in today’s phones. From the component supplier point of view， fewer suppliers actually have both technologies （PA + filter） in-house and lack the expertise to integrate them together. This article will demonstrate a tri-band CDMA RF front end solution using three highly integrated RF modules that take the place of seven discrete components.