4G layered model

4th generation mobile networks were built on a common IP-basedplatform for media access and access to core networks. Handover or roaming supports both handover to other broadcast facilities and to other networks. The goal of 4G activities is to provide unrestricted service diversity worldwide.

A 4G layered model has been designed for 4G to meet these requirements. The model comprises several layers and is based on the hard-wired layer, the fixedlayer. This layer provides static connections on the physical media. These can be cables, but also wireless connections in WLL networks. The Personal Network Layer above it is used to connect terminal devices over short distances using wireless transmission technology. These include Bluetooth, HomeRF and DECT, which can be used to connect telephones, PADs, notebooks or palmtops, as well as intelligent sensors from household appliances.

The hot spot layer, which is located above the personal network layer, supports individual links and is suitable for applications with very high transmission rates. The hot spot includes WLAN systems such as 802.11 and HiperLAN and enables communication in larger areas such as airports, exhibition centers, company premises, etc.

Above the hot-spot layer, there is the metropolitan network layer for connection to core networks and the various cellular layers, cellular layer for microcells and macrocells. It provides high transmission rates and global roaming. The top layer of the 4G layer model is the Distribution Layer, which supports broadband transmission systems for broadcast, including DigitalAudio Broadcast( DAB), Digital Video Broadcast( DVB) and satellite systems.

Some of the layers are used in the other generation networks. For example, the Cellular Layer is used for macrocells in 1st and 2nd generation cellular networks, and the Hot-Spot Layer, Metropolitan Layer and Cellular Layer are used for microcells in 3rd generation cellular networks.