3GPP Network Types

The Third Generation Partnership Project (3GPP) was formed to coordinate the development of 3G Universal Mobile Telecommunications System (UMTS), but also inherited responsibility for 2G Global System for Mobile Communications (GSM). GSM uses multi‐frequency network techniques, and each cell or sector generated by a base transceiver station (BTS) can consist of one more separate radio carriers. 3G UMTS networks were developed by 3GPP as an evolution of the popular 2G GSM standard. 3GPP developed a successor to 3G UMTS known as Long Term Evolution (LTE). A 3.5G evolution of UMTS, known as High Speed Packet Access (HSPA), was developed by 3GPP; several iterations of HSPA and HSPA + have been subsequently released. In LTE‐Advanced (LTE‐A) signalling and control activities all take place via one cell, known as the Primary Cell (PCell); additional traffic connections can be established via up to four Secondary Cells (SCells).