US Patent 8416882 Digital amplitude control of vector generator

In an exemplary embodiment, an active vector generator is configured to generate a composite vector with controlled phase and amplitude, where the active vector generator generates the composite vector with independent variable phase control and independent variable amplitude control. Furthermore, in another exemplary embodiment, an active vector generator is configured to generate a unique number of phase states and configured to generate a unique number of amplitude states. Specifically, an exemplary active vector generator comprises a digital-to-analog converter (DAC) configured to set the phase of the composite vector, a current multiplying switch network configured to control the amplitude of the composite vector, a variable current multiplier configured to adjust the amplitude of the composite vector, and a differential adder configured to control the quadrant of the composite vector and generate the composite vector.