Patent ID: 6417712
Filing Date: 2002-07-09
Classification: H03C,H03H,H03K

Abstract:
A phase shifter comprising:a phase splitter for producing two phase quadrature signals from an input signal; a weighting circuit for producing two weighting signals in accordance with sine and cosine functions of a control signal; two multipliers for multiplying each of the two phase quadrature signals by a respective one of the two weighting signals to produce a respective one of two products; and a summing circuit for summing the two products to produce an output signal which is phase shifted from the input signal in dependence upon the control signal; wherein the weighting circuit comprises two translinear sine shaping circuits each having differential current outputs providing a respective one of the two weighting signals from input currents supplied thereto, and a circuit for providing the input currents to the two sine shaping circuits in dependence upon the control signal, the input currents of the two sine shaping circuits being offset relative to one another whereby the differential current outputs of the two sine shaping circuits are provided in accordance with a sine function and a cosine function, respectively, of the control signal.