Designing a Self-Healing Approach to Radio Link Failures in Mobile Handsets

In all radio access technologies, starting with GSM to UMTS and others there exist an event of radio link failure. A radio link failure occurs due to degradation of air interface during an ongoing voice or a data application. The action that has to be taken is defined by their respective specification of 3GPP. Normally, the physical layer (II) detects a radio link failure. When such a failure is found the normal action performed by the mobile is to do a local release of dedicated and signaling links between the mobile and the network which leads to discontinuation of voice or data application. The higher layers are informed. However, this discontinuation can be avoided, if the mobile uses the facilities of multiple radio access technologies (RAT), available to it. The mobile can employ a self-healing approach to continue with application using the services provided by all other RATs. This paper describes such a self-healing system approach.