Patent ID: 6580702
Filing Date: 2003-06-17
Classification: H04B

Abstract:
In a CDMA communication system, a data transmission apparatus comprising:a plurality of CDMA spreaders for spreading a plurality of PCM data inputted from a side of a transmission terminal through a plurality of channels using a predetermined code; a base band signal processor for combining the digital CDMA signals spread by the CDMA spreaders and then processing analog signals; an IF processor for converting the base band signals inputted from the base band signal processor into an intermediate frequency signal; and an RF processor for converting the IF signals into a power-amplified high (radio) frequency signal and outputting the thusly converted signal through an antenna, wherein the base band signal processor comprises, a digital combiner for combining the CDMA digital signals spread by the CDMA spreaders, a digital filter for filtering a signal inputted from the digital combiner, a D/A converter for converting the filtered digital signal into an analog signal, and an analog filter for filtering the converted analog signal, wherein the digital combiner combines a plurality of CDMA signals in synchronization with a predetermined clock signal.