Generally, the present invention provides a method for detecting poor RF conditions, and entering different sleep mode levels or phases in accordance with the RF conditions to save battery power. Mobile device battery life can be conserved when the mobile device detects poor RF conditions and enters a deep sleep mode of operation. In this deep sleep mode of operation the mobile device periodically samples the RF conditions and gradually increases the period between samples when the RF conditions do not improve. Because mobility can change the RF condition for wireless devices even in areas of good RF coverage, the mobile device operating in the deep sleep mode can detect this mobility and thus enhance the probability of entering an idle state, or alternatively, entering a longer power save mode. When the RF condition improves, the mobile device exits from the deep sleep mode and returns to the idle state.