<P> IMT - Advanced intended to accommodate the quality of service (QoS) and rate requirements set by further development of applications like mobile broadband access, Multimedia Messaging Service (MMS), video chat, mobile TV, but also new services like High - definition television (HDTV). 4G may allow roaming with wireless local area networks, and may interact with digital video broadcasting systems . It was meant to go beyond the International Mobile Telecommunications - 2000 requirements, which specify mobile phones systems marketed as 3G . </P> <P> Specific requirements of the IMT - Advanced report included: </P> <Ul> <Li> Based on an all - Internet Protocol (IP) packet switched network </Li> <Li> Interoperability with existing wireless standards </Li> <Li> A nominal data rate of 100 Mbit / s while the client physically moves at high speeds relative to the station, and 1 Gbit / s while client and station are in relatively fixed positions . </Li> <Li> Dynamically share and use the network resources to support more simultaneous users per cell . </Li> <Li> Scalable channel bandwidth 5--20 MHz, optionally up to 40 MHz </Li> <Li> Peak link spectral efficiency of 15 bit / s / Hz in the downlink, and 6.75 bit / s / Hz in the uplink (meaning that 1 Gbit / s in the downlink should be possible over less than 67 MHz bandwidth) </Li> <Li> System spectral efficiency of up to 3 bit / s / Hz / cell in the downlink and 2.25 bit / s / Hz / cell for indoor usage </Li> <Li> Seamless connectivity and global roaming across multiple networks with smooth handovers </Li> <Li> Ability to offer high quality of service for multimedia support </Li> </Ul> <Li> Based on an all - Internet Protocol (IP) packet switched network </Li>

Requirements related to technical performance for imt-advanced radio interface(s)
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