A method and system of transmitting and receiving data in a mobile telecommunications system which reduces power consumption in mobile stations operating within the system. Mobile stations are divided into a plurality of sleep groups and a sleep message, which is transmitted in the control channel...http://www.google.co.uk/patents/US5745860?utm_source=gb-gplus-sharePatent US5745860 - Method and system of data transmission and reception in a mobile station within a radio telecommunications system 
