Patent ID: 7020219

Claim:
A wireless user terminal having radio frequency (RF) communication capability, comprising: a digital baseband; an RF section; an analog baseband coupling said digital baseband to said RF section, wherein said analog baseband further comprises a delta-sigma digital-to-analog converter having a digital input and an analog output comprising: a storage means having stored outputs of the delta-sigma digital-to-analog converter fed by a number of predetermined interpolated samples corresponding to all possible values of said digital input; said storage means coupled to receive said digital input; a plurality of digital-to-analog converters coupled to said storage means to receive said stored outputs, each of said plurality of digital-to-analog converters clocked by multi-phase clocks wherein each multi-phase clock applied to each of said plurality of digital to analog converters is delayed in time with respect to a next one by an oversampling period equal to a Nyquist period divided by the number of predetermined interpolated samples; and a summer coupled to said plurality of digital-to-analog converters for summing all outputs from said plurality of digital-to-analog converters to generate said analog output.