ave fair and efficient unlicensed spectrum sharing, e.g. to avoid possible interference. Another is to ensure QoS for the LTE traffic. The traffic steering for LTE in unlicensed bands is driven by several factors [10]: QoS and QoE enhancements. By aggregation of different bands including licensed and unlicensed bands, the user throughput can be significantly improved, which has higher influence on the perceived quality of services (because higher throughput also provides lower latency). Better radio resource utilization. The traffic steering from congested licensed LTE bands to uncongested unlicensed bands and vice versa can improve the utilization of resources and provide higher average throughputs per user, which gives better QoS/QoE (also on average). Reduction of operational cost. The use of unlicensed bands for LTE traffic steering reduces operational costs due to no license fees for that spectrum, which on the other hand adds capacity, has lower delay in the radio part due to smaller cells, and hence can result in better QoS. Also, lower frequency LTE cells (e.g. below 1 GHz) can be used for providing coverage while LTE in unlicensed band (together with WiFi) can add more capacity in the network. Overall, the use of unlicensed bands in combination with licensed bands is not novel in mobile networks since the introduction of Internet connectivity (e.g. with GRPS by 3GPP) and standardization of WiFi (1997 onwards). However, with carrier aggregation available with 4G, there is the possibility to aggregate different frequency bands in a given direction (e.g. downlink), including licensed bands (e.g. LTE 700 MHz, 800 MHz, and other bands) and unlicensed bands (e.g. 5GHz for LTE and WiFi, 2.4GHz for WiFi carriers), which provides several benefits regarding QoS in mobile and wireless networks, where the most important QoS parameter that is improved is the available throughput as well as mobile/wireless network availability. 5 QoS for Mobile Ultra-Broadband The ITU's IMT-2020 Each new generation of mobile systems a