In the GSM and similar systems, USSD (Unstructured Supplementary Service Data) transfer takes place on a fast channel if a mobile station is involved in that call, and otherwise on a slow channel. The USSD transfer can be switched to the fast channel by determining the amount of data to be transmitted....http://www.google.fr/patents/US6834196?utm_source=gb-gplus-shareBrevet US6834196 - Method for improving the performance of USSD transfer in a cellular communications system
Method for improving the performance of USSD transfer in a cellular ...
