A wireless R&D perspective on RF/IF passives integration

Wireless handset evolution has been, and continues to be, driven by a combination of developments in largely separate but interacting technologies. The relentless progress of radio architectures, digital circuits, and process technologies seems to offer new avenues and opportunities for external passives reduction by elimination or integration. Clearly, passive components face a Darwinian battle for existence as only the nonintegrable and truly uneliminatable survive the inexorable pressure to reduce size and total system cost. Meanwhile, market demands for multi-band, multi-mode products operating at disparate RF frequencies are creating new challenges at the radio system level, which may also open new opportunities for passive component integration. Researchers in industry and academia are responding to these with "integration technologies" from embedded high-density interconnect boards, multilayer ceramic modules, on-chip inductive components and micro-electromechanical systems (MEMS).