The ITU-R IMT-2020 (5G) Vision includes three usage scenarios: Enhanced Mobile Broadband (eMBB), Massive Machine Type Communications (mMTC) and Ultra-Reliable and Low Latency Communications (URLLC). It also specifies the key capabilities of IMT-2020 (Figure 1), which contain great improvements in comparison with the previous generation of IMT systems.
To address diversified requirements from the envisioned 5G usage scenarios, 5G needs access to “high”, “medium” and “low” frequencies (Figure 2), exploiting specific characteristics of different portions of the spectrum: frequencies between 2 and 6 GHz (e.g. 3300-3800 MHz) in combination with frequencies below 2 GHz (e.g. 700 MHz) and above 6 GHz (e.g. 24.25-29.5 and 37-43.5 GHz). A sufficient amount of harmonised spectrum in each layer should be made available by national regulators in a timely manner to enable mobile operators to deliver 5G services.
Bands below 6 GHz are crucial to support most 5G use scenarios in a wide-area. The 3300-4200 and 4400-5000 MHz frequency ranges are suitable to deliver the best compromise between wide-area coverage and good capacity. For the early deployment of 5G, at least 100 MHz contiguous spectrum bandwidth from the C-band should be assigned to each 5G network in order to support user experienced data rate of 100 Mbps anywhere anytime and other 5G technical requirements.
Low frequencies (below 2 GHz) will continue to be essential to extend the 5G mobile broadband experience to wide areas and in deep indoor environments; mMTC and URLLC usage scenarios will also greatly benefit from the low frequencies’ extended coverage. The available low frequency bands (e.g. 700, 800, 900, 1800 and 2100 MHz) may be exploited for LTE/NR uplink spectrum sharing in combination with NR on the C-band to allow operators to ensure faster and cost-effective deployment of C-band.
High frequencies (above 6 GHz) will prove indispensable for providing additional capacity and delivering the extremely high data rates required by some 5G eMBB applications. At least 800 MHz per network of contiguous spectrum bandwidth from high frequencies is recommended for initial the early deployment of 5G.
The assignment of contiguous wide spectrum bandwidth in each layer reduces system complexity associated with carrier aggregation, which will improve energy efficiency and reduce network cost.
.Recommendation ITU-R M.2083, “IMT Vision – Framework and overall objectives of the future development of IMT for 2020 and beyond”.