| Popis: |
The deployment of LTE in unlicensed spectrum has recently been proposed to improve cellular data capacity. Under the title of License Assisted Access (LAA), 3GPP is developing a global standard to enable operators of licensed spectrum to expand into unlicensed spectrum. For regions with less restrictive regulations, the LTE-U Forum has developed a proprietary implementation based on LTE Release 12. Both implementations use carrier aggregation to bond licensed and unlicensed spectrum. This paper investigates the performance of unlicensed LTE using a simulated case study based on a real urban network deployment. Unlicensed LTE is deployed outdoors and is co-located with licensed band LTE picocells. The performance of this network is compared with the identical network using Wi-Fi in the unlicensed band. Results show that unlicensed LTE outperforms Wi-Fi, but the degree depends on the interaction between Wi-Fi and the licensed carrier. In addition, the coexistence of unlicensed LTE using a generic, static muting approach (LTE-U) and Wi-Fi is studied for the case of a single operator. The coexistence results, addressing only the scenario of a single operator with a mixed outdoor deployment in a defined geographic area, show that LTE-U can be configured to yield network performance gains while being fair to the Wi-Fi network. |
