Licensed Shared Access Concept Research Articles

Field Trial of Licensed Shared Access with Enhanced Spectrum Controller Power Control Algorithms and LTE Enablers

This paper presents the results from a field trial of the Licensed Shared Access (LSA) concept using TD-LTE network in the 3rd Generation Partnership Project spectrum band 40 (2.3–2.4 GHz) in Finland. In the field trial, the LTE network shared the spectrum with a program making and special events Incumbent. New LSA concept elements, LSA Repository for Incumbent protection information and LSA Controller for controlling the mobile broadband network in the same spectrum band were implemented in the trial environment. The trial utilized commercially available network elements like multimode multiband terminals, LTE base stations, core network and network management system. Incumbent spectrum usage data was collected to the LSA repository, which further converts it to spectrum availability information for the LSA controller. The trial goes beyond previous LSA demonstrations by presenting LSA controller power control concept algorithm that formulate the optimization objective as a function of base station cell transmit powers. An advantage of this procedure is that considering aggregated interference from the LTE network to Incumbent and adjusting the transmit power levels do not result in abrupt changes in the received signal quality and results better overall throughput. The developed LSA controller was implemented as self-organizing network solution integrated into network management system. Numerical results are presented to quantify the duration of the LSA procedure flow. The performance results on the LSA system workflow indicated that in the program, making special event use case the LSA band can be managed timely manner and the Incumbents’ rights can be protected.

Spectrum sharing using licensed shared access: the concept and its workflow for LTE-advanced networks

Spectrum sharing between an existing incumbent spectrum user and an LTE/LTEAdvanced network with conditions that resemble exclusive licensing have become an appealing solution for mobile network operators to respond to the growing traffic and spectrum demand in a timely manner. While traditional exclusive licensing continues to be the preferred option for MNOs, the new sharing- based licensed shared access (LSA) concept is receiving growing interest in research, regulation and standardization. When applied to mobile communications, the LSA concept would allow an MNO to share spectrum from another type of incumbent spectrum user under a regulator?s supervision with predetermined rules and conditions that guarantee operational certainty for both MNO and incumbent. This article reviews different types of spectrum bands for LTE/LTE-Advanced and beyond networks, and focuses on the LSA concept as a spectrally efficient solution for spectrum access in the future. The article identifies the key stakeholders, including the incumbent spectrum user, the MNO, and the regulator, and their roles in the LSA concept. The key elements in the LSA concept are reviewed, and a work flow for the life cycle of the LSA concept is proposed, consisting of LSA preparation, licensing, deployment, and release phases. The tasks of the key stakeholders in the different phases of the LSA work flow are discussed. The LSA concept can offer a complementary approach to traditional exclusive licensing and license-exempt operations with features that benefit all involved stakeholders. It can be realized with reasonable modifications to the existing network infrastructure and regulatory framework with two new elements for managing the varying spectrum availability: the LSA Repository and LSA Controller.