In the first part of the paper, we modeled and characterized the underwater radio channel in shallowwaters. In the second part,we analyze the application requirements for an underwaterwireless sensor network (U-WSN) operating in the same environment and perform detailed simulations. We consider two localization applications, namely self-localization and navigation aid, and propose algorithms th...

Underwater acoustic communication (UWAC) is often the only viable solution to establish an ad-hoc underwater communication network. The specific features of UWAC, arising from the physics of underwater acoustics, make the design of resource-efficient media access control (MAC) protocols important as well as challenging. In this paper, we tackle this task considering ad-hoc UWAC networks that su...

In multi-hop underwater acoustic sensor networks (UWASNs), packet collisions due to hidden and local nodes adversely affect throughput, energy efficiency and end-to-end delay. Existing medium access control (MAC) protocols try to solve the problem by utilizing a single-phase contention resolution mechanism, which causes a large number of control packet exchanges and energy overhead. In this pap...

Medium access control (MAC) protocols have been studied under different contexts for several years now. In all these MAC protocols, nodes make independent decisions on when to transmit a packet and when to back-off from transmission. In this paper, we introduce the notion of node cooperation into MAC protocols. Cooperation adds a new degree of freedom which has not been explored before. Our joi...

Medium Access Control (MAC) protocol is one of the key network protocols that ensure Wireless Sensor Networks (WSNs) maintain high performance during communication. MAC protocol design plays an important role in improving the performances of the whole network. First, Wireless Passive Sensor Networks (WPSNs) and MAC protocols are introduced in this paper. Second, some existing MAC protocols are ...

The MAC (Medium Access Control) protocols can be roughly categorized into three broad classes [16]. The fixed assignment set will have schemes like TDMA, CDMA and FDMA. These protocols lack the flexibility in allocating resources and thus have problems with configuration changes. This makes them unsuitable for dynamic and bursty wireless packet data networks. The random assignment class consist...

Underwater networking is a recently evolving technology which promises to provide the required infrastructure that will further cooperation amongst Unmanned Underwater Vehicles (UUVs). Underwater networks face extreme challenges of low bandwidth, high latency, and minimal energy resources. AUSI team has made its initial efforts to address the issues of underwater networks and as a result develo...

Using analytic models and simulation results, we examine spatial reuse and the effectiveness of RTS/CTS MAC protocols in underwater acoustic networks. We are not looking at the question of network throughput, which is affected mostly by propagation delay, but rather the protocol’s ability to prevent collisions. RTS/CTS-based collision-avoidance protocols require successful detection of the hand...

CR and PU hidden terminals in multi-channel Cognitive MAC protocols result in increased packet drops. This is due to inefficient node synchronization with existing “Control Channel” design. To date, In-band and Out-of-band CCC based MAC protocols are proposed to avoid PU and CR hidden terminals. But, In-band CCC based CR-MAC protocols cannot efficiently resolve the hidden terminal packet drops ...

Wireless Sensor Network (WSN) is an attractive choice for a variety of applications as no wired infrastructure is needed. Other wireless networks are not as energy constrained as WSNs, because they may be plugged into the mains supply or equipped with batteries that are rechargeable and replaceable. Among others, one of the main sources of energy depletion in WSN is communications controlled by...