many performance evaluations for ieee 802.11distributed coordination function (dcf) have been previouslyreported in the literature. some of them have clearly indicatedthat 802.11 mac protocol has poor performance in multi-hopwireless ad hoc networks due to exposed and hidden nodeproblems. although rts/cts transmission scheme mitigatesthese phenomena, it has not been successful in thoroughlyomit...

designing wireless sensor networks should meet appropriate parameters such as quality of service (qos) defined by different users. the variable physical conditions of the environment, processing and transmission power limitations and limited communication capabilities are the most important obstacles that influence qos parameters such as throughput, delay, reliability and network lifetime. the ...

An IEEE 802.11ah network has been designed to service a wide range of sensor network applications where a single access point (AP) covers a transmission range of up to 1 km and needs to support more than 80 0 0 nodes. As a result, it has much more hidden node pairs compared to conventional 802.11a/b/g/n/ac networks. In addition, since nodes in power saving mode wake up simultaneously to send fr...

Local Coupled Extreme Learning Machine (LCELM) is a recently-proposed variant of ELM, which assigns an address for each hidden-layer node and activates the hidden-layer node when its activated degree is less than a given threshold. In this paper, an improved version of LCELM is proposed by developing a new way to initialize the address for each hidden-layer node and calculating the activated de...

This paper orders certain important issues related to both uncorrelated and correlated networks with hidden variables, in which hidden variables correspond to desired node degrees. In particular, we show that networks being uncorrelated at the hidden level are also lacking in correlations between node degrees. The observation supported by the depoissonization idea allows us to extract a distrib...

Ascertaining the existence of hidden objects in a complex system, objects that cannot be observed from the external world, not only is curiosity-driven but also has significant practical applications. Generally, uncovering a hidden node in a complex network requires successful identification of its neighboring nodes, but a challenge is to differentiate its effects from those of noise. We develo...

The introduction and growth of large, metropolitan-sized wireless networks has identified a significant problem within the current 802.11 protocol specification; Hidden Nodes. A wireless network may have 2 nodes, A and B, connected to a central Access Point (AP). Node A is within the transmission radius of the AP, but outside the transmission radius of B, and vice versa. Nodes A and B are then ...