A Design Methodology for Low-Power Active Analog Filters for Wireless Communications

A design methodology for low-power analog filters is reported. In order to reduce the power consumption, power optimization is included at three different levels of the filter design flow. First, an appropriate transfer function is selected fulfilling the required input-output relation specifications. Then, an orthonormal ladder filter structure is chosen as it offers the best filter topology choice. Finally, a low-power circuit implementation of the transconductor cell, the main building block in gm-C filters, is devised. The design procedure is illustrated by the design of a baseband filter required in a wireless receiver for WLAN (IEEE 802.11g standard).