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Bluetooth Low Energy (BLE) is a popular low power wireless technology, used for short-range communication. In BLE networks, discovery process enables fast and energy-efficient communication, since ...

Spectrum sensing (SS) is one of the key tasks in cognitive radio networks that is performed to get awareness about the usage of electromagnetic spectrum. It enables the secondary user (SU) to detect the presence/absence of primary user (PU) and plan its transmission strategy accordingly. The aim of SS is to detect the presence or absence of PU in a certain frequency band and allow or prevent the SU's transmission on the basis of sensing result. In this paper, a review on different SS techniques is presented in the context of PU detection. We mainly focus on non-cooperative SS methods used for the PU detection. PU is the incumbent user in cognitive radio networks, and its transmission should not be interrupted. Moreover, it can start its transmission at any time, so the SU has to sense a channel before starting its transmission and monitor the arrival of PU continuously as long as it utilizes the channel to avoid any interference. The PU detection techniques are further divided into five main categ...

Providing a continuous connection in heterogeneous wireless networks is a challenging job. Traditional approaches are mainly concerned to specific scenarios. These approaches are also suffering from different problems like ping-pong effect, inappropriate handover triggering, etc. Therefore, to provide a generic connectivity in heterogeneous wireless networks, we proposed a vertical handover decision scheme. The proposed scheme performs handover triggering using simple additive weighting on the data rate of a point of attachment (PoA). The user calculates the data rate required by different applications and then compares it with a predefined threshold. Similarly, the network selection is performed using Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) decision model on different parameters such as delay, jitter, bit error rate, packet loss ratio, communication cost, response time, and network load. The PoA of a network calculates its rank using TOPSIS and sends it to the u...

The advancement of new technologies such as LTE-Advanced, WiMAX rel 2, and IEEE 802.11ac standards provides high data rate for mobile users across heterogeneous networks. The increase in data rate also provides support for multimedia and real-time applications. In order to provide better services and uninterrupted connection, a generalized connectivity must be provided to the mobile user across these technologies. In this article, we survey different techniques used to modify the existing Media Independent Handover standard of the IEEE 802.21 and how they reduce handover delay across heterogeneous networks. Furthermore, different parameters such as receive signal strength (RSS), signal-to-interference and noise ratio, data rate, bandwidth, energy consumption, user preferences, cost, and speed of a mobile node are taken into consideration which directly and indirectly affect a handover management process in heterogeneous wireless networks.