GC5318IZED

GC5318IZED 1.1 Features

• Optimized for CDMA2000-1X and UMTS • Up to 12 UMTS or 24 CDMA2000 UpconverterChannels • Mixed CDMA2000-1X and UMTS Operation • DUC Output Rates to 125 MSPS • Any DUC Can Sum into Any of Four OutputPorts

GC5318IZED 1.1.1 Description

The GC5318 is a high-density multi-channel communications signal processor integrated circuitthatprovides digital upconversion optimized for cellular base transceiver systems. The device supports bothUMTS and CDMA2000 (CDMA) air interface cellular standards.The chip provides up to 24 CDMA digital upconverter (DUC) channels or 12 UMTS DUC channels. TheGC5318 can also support a combination of CDMA and UMTS channels. The DUC channels operatesimultaneously.The chip is ideal for cellular base transceiver systems where a large number of digital radio channels arerequired. Each of the 24 CDMA (or 12 UMTS) channels can operate independently.There are four 18-bit output ports. Each output port can sum any of the DUC channels in a daisy-chainfashion. This configuration permits creating a stack of CDMA or UMTS signals. These ports can outputeither real or complex data. Real output data would generally drive one or more digital-to-analog (D/A)converters and output the stack of signals at an intermediate frequency (IF). Complex data (at basebandor an IF) is used when a quadrature modulator upconversion scheme is employed. Complex output datacan also be used when the output stack is further processed using crest factor reduction or poweramplifier predistortion techniques.