MSK modulator, angle modulator, digital signal generator, MSK modulation method and recording medium

摘要

PROBLEM TO BE SOLVED: To provide an MSK modulator or the like for accurately operating MSK modulation by high speed data in a digital format.;SOLUTION: When a digital signal to be modulated is supplied from a code generator 1, a bi-directional shift register 2 operates the cyclic shift of a 16 bit column stored in its own device to a direction decided by the logical value of the supplied digital signal. A weighting adder 3I weights and adds the logical value of each lower 5th and 12th bit in this bit column and a weighting adder 3Q weights and adds the logical value of each lower 1st-8th in this bit column, and generate two analog signals whose phases are different by (π/2) radian. The analog signal generated by the weighting adder 3I is multiplied by a signal generated by a first local oscillator 7, and the analog signal generated by the weighting adder 3Q is multiplied by a signal generated by a phase shifter 8. The two multiplied results are added by an adder 9 so that an MSK modulated wave can be generated.;COPYRIGHT: (C)2000,JPO