The establishment of digital connections is avoided if the power level compensated uplink signal strength transmitted by a dual-mode mobile station is below a threshold value. In such cases, a dual-mode mobile station is instead preferably connected to an analog traffic channel. The threshold value can...http://www.google.se/patents/US6112093?utm_source=gb-gplus-sharePatent US6112093 - Radio communication system and method for analog and digital traffic channel allocation using a second higher threshold when allocating a digital channel
