Long-Term Evolution (LTE) is an emerging wireless technology that many of today’s service providers are planning to deploy. LTE is considered the next-generation technology in wireless communications, offering broadband access rates on wireless devices. This allows mobile wireless devices the ability to offer services that fixed-line broadband customers are accustomed to such as high-speed data, stereo-quality audio, and streamed high-definition TV (HDTV).
For LTE, femtocell standardization is part of the initial base standard which allows LTE femtocell issues to be addressed early on in the development of LTE. Femtocells may also assist in the deployment of LTE services from the perspective that the distribution of LTE NodeB radio transceiverswill need to be significantly denser. Having to deploy significantly more NodeB radio transceivers spread across their coverage areas becomes a challenge, since there are a limited number of existing radio towers at their disposal. Using femtocells, service providers can extend coverage to any location where broadband access is available. This significantly increases a carrier’s ability to provide LTE coverage in areas that were not feasible before. The illustration below shows a high-level diagram of a LTE network that includes a femtocell network.
The mobile phone, also known as the user equipment (UE), interfaces with a Home eNodeB (HeNB) overthe- air interface. The Home eNodeB is a device that resides in the customer’s home that is analogous to the Femto Forum’s FAP. The HeNB is a miniature eNodeB providing wireless LTE coverage in the customer’s home. The HeNB interfaces to the mobile network operator (MNO) over a broadband network by interfacing with a broadband access gateway. The mobile operator’s core network obtains access to the HeNB connected to a broadband access device via a security gateway. The security gateway is used to protect the core network against attacks. On the trusted side of the security gateway resides the Home eNodeB Gateway (HeNB GW). The HeNB GW is responsible for aggregating traffic from a large number of HeNBs and interfacing with the mobile operator’s Evolved Packet Core (EPC) network. The S1-MME interface carries data using the LTE S1-MME interface. The HeNB interfaces with the EPC using a LTE S1-U interface via the security gateway.
