资 源 简 介
The fast growing of the wireless market has created an urgent demand forsmaller and cheaper handsets with increased funcTIonality and performancewhile sTIll meeTIng the TIght constraints for mass production within a shortproduct life cycle.The successful achievement of these conflicting trends has been possibledue to the development of key technical capabilities in the design andproduction of each new wireless device generation.In the baseband section of the handset, the great developmentexperimented by the CMOS processes in the last decade, has shrunk thesilicon real estate required for the processor, memory and interface ICs.The advanced chip scale package (CSP) techniques and multi-layerlaminate printed circuit boards (PCB) have minimized the electronicinterconnect and packaging volume. The battery technology has advancedfrom the older nickel cadmium and nickel metal-hydride to the lithium ionand lithium polymer technologies, improving the battery pack size, weightand performance. The antenna has migrated from outside in the old designsto inside the plastic housing in the new ones, giving more freedom in thehandset form and design. As it is shown in Figure 1-1, all theseimprovements have led to lighter, smaller and compact handsets.In contrast to this situation, the improvement in the passive componentcontent of the handset has been much less dramatic compared to othertechnical areas. This inertia has not been due to the lack of attention by theset-makers or in the literature.
