## 1 Introduction  
In recent decades, piracy represents a growing trend, especially in the less regulated international waters, such as South-East Asia, East and West Africa and Caribbean [1]. In the East Africa, during the last few years, piracy has decreased due to the intervention of the International organizations [2, 3]. Unfortunately, this decrease of pirate attacks in the East Africa does not mean that all other regions in the World experienced the same trend. On the contrary, some regions experienced a tremendous increase, such as the Gulf of Guinea [4, 5, 6]. In situations such as this, nearly all maritime nations are forced either to increase safety of their waters and Exclusive Economic Zones (EEZs) or to suffer significant losses both in human lives and goods rightfully belonging to them. Unfortunately, EEZs are huge bodies of water stretching over hundreds of thousands square miles, which makes their complete surveillance quite challenging endeavor. Although primarily developed for a remote measurement of the ocean surfaces and collection of oceanographic data such as wave spectra or sea currents [7, 8, 9, 10], High Frequency Surface Wave Radars (HFSWRs) nowadays find an increasing usage in the vessel detection and tracking at over the horizon (OTH) distances [11; 12; 13; 14; 15; 16]. The major advantage of the HFSWRs compared to the sensors usually used for maritime surveillance (such as microwave radars, electro-optical systems) is its coverage area of about 200 nautical miles, which corresponds to the EEZ. Moreover, HFSWRs provide that capability at a price tag far lesser than the price of microwave sensors and moving platforms (such as vessels and aircrafts) needed to overcome the microwave sensors disadvantages and thus cover complete EEZ. Furthermore, since HFSWRs do not require moving platforms, they can monitor the sea surface and track vessels continuously during the whole year and under all weather conditions. Despite the fact that the term Internet of Things (IoT) is usually related to sensor networks consisting of small size sensors which have limited coverage area [17], IoT can also refer to physically large sensors which can individually cover an area greater than 100,000 km\({}^{2}\). The example of such application is development of a maritime surveillance network based on HFSWRs, named IoT OTH maritime surveillance sensor network. The HFSWR used as the primary IoT over the horizon sensor in the Gulf of Guinea (and thus in this paper) has been produced by the Vlatacom Institute [18] and thoroughly described in [19]. However, in spite of its great coverage area, a single HFSWR is not enough to provide uninterrupted surveillance over the complete EEZs of some countries. So, the network of HFSWRs needs to be deployed in order to cover the area of interest. Thus, one problem--the complete EEZ coverage is solved, yet another issue is opened--communication between sensors deployed at different remote sites along huge areas and Command and Control Centers (C2). Unfortunately, in developing countries the communication infrastructure is quite often underdeveloped [20; 21], especially in remote areas. To make the already bad situation worse, the Gulf of Guinea is located in the African Equatorial belt thus adding quite harsh environmental factors that influence the signal transmission and vessel detection [22; 23]. In our previous work [24] we have demonstrated the Laboratory for IoT communication infrastructure environment for remote maritime surveillance, which simulates effects of the satellite link as a part of IoT communication layer. In this paper, we will demonstrate the complete IoT environment built around HFSWRs as primary sensors in equatorial area, which uses satellite communication as a feasible communication solution. The performance analyses consider the complete IoT OTH maritime surveillance service, not only the transmission via the satellite link.