The load on the communications resources of a cellular telephone system is monitored to detect instances of excess amounts of unused resource capacity. When such instances are detected, a message is transmitted to subscribers via the cellular system offering reduced charging rates for calls...http://www.google.es/patents/US5794140?utm_source=gb-gplus-sharePatente US5794140 - Method and apparatus for offering subscribers access to unused communications capacity in a cellular communications system
Method and apparatus for offering subscribers access to unused ...
