Low-Power Quadrature Receivers for ZigBee (IEEE 802.15.4) Applications

Abstract

Two very compact and low power quadrature receivers for ZigBee applications are presented. Area and power savings are obtained through both current reuse and oscillator tank sharing between the I and Q paths. Since this choice can cause I and Q amplitude/phase mismatches, the conversion gain is analyzed and a technique to minimize these errors is implemented. Moreover, since using a single tank makes quadrature generation at the local oscillator level costly and power-hungry, two alternative quadrature generation techniques in the RF path are proposed, together with the corresponding input matching strategies.