Читать книгу Dynamic Spectrum Access Decisions - George F. Elmasry - Страница 109

With this case, SAs can share spectrum sensing information in a distributed manner along with their geolocation information if they are not publically known to be static.¹⁹ In this case, each SA is a fusion center of spectrum sensing information and the spectrum sensing information shared is abstracted as a spectrum map after fusion.

Figure 6.13 points to a potential disadvantage of this approach as the SA working autonomously will require a control plan to be created to exchange the spectrum map information, as Figure 6.13 shows. This control plan goes through the macrocell, which is supposed to have the most processing power and can act as the centralized fusion center.

Figure 6.13 Autonomous SAs in a distributed cooperative fashion and their control place.

There are reasons for ensuring the SAs can operate autonomously. Consider the case of deploying 5G communications assets in a disaster area where there is no macrocell to reach out to. There is a need to ensure that dynamically deployed small cells with SA capabilities can perform DSM decisions autonomously, in addition to being access points. The deployed small cells will have spectrum sensing fusion capabilities and the means to share spectrum sensing information with other small cells to make DSM decisions independently of a large tower (macrocell).