# Dynamic Cooperative MAC Protocol for Navigation Carrier Ad Hoc Networks: A DiffServ-Based Approach
###### Abstract  
In this paper, a dynamic cooperative MAC protocol (DDC-MAC) based on cluster network topology is proposed, which has the capability of differentiated service mechanisms and long-range communication. In DDC-MAC, heterogeneous communications are classified according to service types and quality of service (QoS) requirements, i.e., periodic communication mode (PC mode) is extracted with a QoS guarantee for high-frequency periodic information exchange based on adapt-TDMA mechanisms, while other services are classified as being in on-demand communication mode (OC mode), which includes channel contention and access mechanisms based on a multiple priority algorithm. OC mode is embedded into the adapt-TDMA process adaptively, and the two communication modes can work in parallel. Furthermore, adaptive array hybrid antenna systems and cooperative communication with optimal relay are presented, to exploit the opportunity for long-range transmission, while an adaptive channel back-off sequence is deduced, to mitigate packet collision and network congestion. Moreover, we developed an analytical framework to quantify the performance of the DDC-MAC protocol and conducted extensive simulation. Simulation results show that the proposed DDC-MAC protocol enhances network performance in diverse scenarios, and significantly improves network throughput and reduces average delay compared with other MAC protocols. N  
A _Article_  
Dynamic Cooperative MAC Protocol for Navigation Carrier Ad Hoc Networks  
A DiffServ-Based Approach  
1,2,*, *,  
is surveyed as a new network family. Moreover, some of the protocols and mechanisms have already been investigated, including (i) the protocol framework, and the models in the physical layer [2; 3]; (ii) a distributed multi-weight data-gathering and aggregation protocol for cluster topology, i.e., DMDG protocol [2]; (iii) a grid-based cooperative QoS routing protocol with fading memory optimization, i.e., FMCQR protocol [3]; and (iv) a network-based localization mechanism [4]. As part of a series of research work, the main objective of this paper is to develop a MAC protocol with full account of the features of NC-NET. Figure 1 illustrates a typical use of NC-NET, which is a scenario of multi-service transmission among a set of unmanned aerial vehicles (UAVs); herein, each UAV is equipped with an NC-NET terminal with a unique ID, and thus the objective node \(s\) will exchange the wireless packets with its neighbors \(C_{M(i)},i\in\{1,2,\ldots,10\}\) at each round, according to the uniform NC-NET protocols. Thus, in this kind of application, an efficient MAC protocol is indispensable for NC-NET, which has the following design challenges: (i) multiple traffic services; (ii) three-dimensional large-scale active region (e.g., aerial, ground or water surface), and long-range distance between nodes (e.g., line-of-sight, beyond-line-of-sight); and (iii) heterogeneous types of NC-NET nodes. For simplicity, but without loss of generality, an essential NC-NET is discussed at length in the research, in which the open issues surrounding general-purpose MAC protocols are analyzed in detail. However, there are also several common points between NC-NET and the previous ad hoc network, e.g., decentralization, infrastructure-less, and self-configuration [2; 3; 5]. Moreover, several illustrations of NC-NET adopt the general-purpose technologies of ad hoc networks, such as TDMA and CSMA/CA. From this point of view, NC-NET can also be investigated as a special form of ad hoc network. In previous literature, several effective technologies for MAC protocols have been studied in depth, which can be used as a reference for our research, e.g., directional antennas, multi-channel diversity, differentiated-service mechanisms, and cooperative communication. There are several common points between NC-NET and previous ad hoc networks, such as decentralization, lack of infrastructure, and self-configuration [6; 7].