Implementing opportunistic spectrum access in LTE-advanced

Abstract

Long term evolution advanced (LTE-A) has emerged as a promising mobile broadband access technology aiming to cope with the increasing traffic demand in wireless networks. However, the enhanced spectral efficiency offered by LTE-A may become futile without a better management of scarce and overcrowded electromagnetic spectrum. In this sense, cognitive radio (CR) has been proposed as a potential solution to the problem of spectrum scarcity. Among all the mechanisms provided by CR, opportunistic spectrum access (OSA) aims at a dynamic and seamless use of certain licensed bands provided the licensee is not harmfully affected. This operation requires spectral awareness in order to avoid interferences with licensed systems. In spite of implementing some spectrum sensing mechanisms, LTE-A technology lacks other tools that are needed in order to improve the knowledge of the radio environment. This work studies the adoption of a Geo-located data base (Geo-DB) that cooperatively retrieves and maintains information regarding the location of unutilized portions of spectrum potentially available for OSA. Moreover, the potential benefit of this LTE-compliant OSA solution is evaluated using a calibrated simulation tool, by which numerical results allow us to optimally configure the system and show that the proposed opportunistic system is able to significantly improve its performance.

Revamp of eNodeB for 5G networks: Detracting spectrum scarcity

“…The steps for the proposed RB handoff algorithm to mitigate CCI are as follows: operates as a SU. Along with the above proposed procedure to share the unused resources by the operators, extensive research is underway to make use of unused spectrum band, freed by digitization of TV transmission, for providing an additional resource for the future generation networks [1,17]. This unused spectrum resource is called TV white space (TVWS) and its information is maintained in a database called geo-location database.…”

Immuno-neural network for spectrum prediction

“…The slot configuration in the LTE-Advanced network showing the MGL, MGRP and the DTT is given in [4] and shown in Figure 1 to improve the clarity of this paper. The MGL and the ISAT are considered equivalent in subsequent discussions.…”

“…The measurement gap length (MGL) is the ISAT [4]. The measurement gap repetition period (MGRP) comprises the MGL and the data transmission time (DTT).…”

Statistical interference maps for opportunistic spectrum access in OFDMA cellular networks

“…However, the load in cellular networks varies between different areas and time intervals. Therefore, there has been recent research interest to study the feasibility and determine the gains of opportunistically utilizing the cellular network spectrum by secondary users [1], [2].…”