| 摘要 |
In a 3GPP LTE-A support for Mobile Type Communications, that is, M2M communications scheme, improvements of the random access are necessary to prevent random channel overload. Enhanced back¬ off in the presence of overload is such a mechanism, Counting the number of devices seeking RACH based on the number of received random access requests or else responses, and allocating Random Access resources on the basis of the number of requests, is another. Further, a channel aware resource allocation approach provides a way of determining, from the received requests, delay-tolerance of the M2M devices, based on which they are prioritised in accessing the random channel. Even within the prioritised devices, a smaller subset thereof may be prioritised further, according to radio conditions, to provide better access to those with higher SNR RBs. |
