The popularity of Software Radios is increasing, as they have become one of the important emerging technologies in mobile communications. One of the major challenges during development of mobile communications hardware is the inevitable low power requirement. In this paper, we investigate power management for software radios. The use of resolution adaptive analog to digital converters as well as the flexibility of the modulation schemes that a reconfigurable radio provides is investigated. The concept of a resolution adaptive analog to digital converter is to trade performance for energy efficiency. The energy delay product is used to evaluate the performance versus energy tradeoffs and an adaptive power management method is proposed.