DIGITAL WAVEFORM GENERATOR APPARATUS AND METHOD THEREFOR

A dual mode wireless device in which a coefficient generator (42) generates parameter values for a GSM waveform, based on transmitted sequences of digital data values from a GSM unit (34), using a multiplierless operation, and a waveform generator 44 generating the GSM waveform using the generated parameter values. The coefficient generator includes adder sections (132, 134, 136), each having corresponding adders (142, 144, 146) and multipliers (148, 150, 152), register sections (154, 156, 158), each containing parameters corresponding to a modulator (48), and transmit data registers (TXDATA[5]-TXDATA[0]) sequentially receiving the digital data values from the GSM unit. The coefficient generator generates the parameter values for the GSM waveform by multiplying each of the parameters in the register sections by a one or a negative one, responsive to the digital data values in the transmit data registers, and adding the resulting products to form corresponding coefficient generator output values.