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This paper presents a novel application of software radio (e.g., Sora) for hand gesture recognition by using long training symbols. The type of gesture performed between the transmitter and receiver can have significant effects on the received wireless signals (e.g., IEEE 802.11a). Since all wireless signal processing functions could be done completely in software, we can easily capture the two long...
Localisation in wireless sensor network is the process of determining the geographical location of the sensor nodes. Conventional localization is space oriented which uses GPS (Global Positioning System) signal to obtain the location information of the nodes. But the GPS signals fail to work in indoor environments, the reason for which it becomes mandatory to opt for terrestrial localisation. The...
This work examines the charging power allocation and beam selection problem for distributed estimation in wireless passive sensor networks, where the sensors are charged over the air by RF-enabled energy sources. A two-phase replenishment and transmission cycle is considered. In the replenishment phase, each wireless charger emits power over the air through a carefully selected beam and power to replenish...
In this paper, we examine the exploitation of individual patterns of behavior to enhance indoor positioning of pedestrians.We make use of the fact that, due to habits and needs, a person is likely to be in some locations more often than others. For example, at their work or in their home, a person is likely to spend more time in some rooms than in others. Therefore, it seems natural to take advantage...
This paper proposes an efficient channel estimation method based on comb pilots. This method is used for OFDM system under time-variant conditions. When under the high speed mobile channel, Doppler frequency shift will cause serious inter-carrier interference (ICI). As it is known, the ICI is manifest as noise in many cases. Therefore, a low pass filter can be used in the transform domain to reduce...
This paper proposes a novel localization scheme to estimate the location of the mobile device by using single reference device. This scheme makes use of the bidirectional information of the line of sight (LOS) and non line of sight (NLOS) paths to construct the area of possible mobile device (APMD) and line of possible mobile device (LPMD) respectively. The location of the mobile device is determined...
Secret-key agreement from reciprocal wireless channels has been considered a valuable supplement for security at the physical-layer. On the one hand, full-duplex (FD) communication is regarded as one of the key technologies in future 5G systems. On the other hand, the success of 5G depends, among other things, on the ability to allow for secure communication. However, most key agreement models are...
In this paper, a low complexity microwave based direction finding (DF) system is presented. The proposed system consists of single six-port (SP) circuit integrated with a reconfigurable multiple-input-multiple-output (MIMO) antenna system. The proposed design is a complete integrated solution with DF capabilities for cognitive radio platforms. The design is suitable to be used in compact wireless...
SDN is a new approach to manage networks with a centralised, global view and control of the network, and a more fine grained and flexible approach to routing and forwarding of data packets. This has shown to achieve significantly increased network efficiency in a range of wired networks. SDN also has a great potential for wireless networks. One of the unique challenges of applying the SDN approach...
In this paper, a method for improving wireless localization of active targets in indoor environments is proposed. The positioning problem is recast to an inverse problem and solved by means of multi-objective evolutionary optimization. The first objective considers received signal strength wireless positioning based on a theoretical propagation model. The second objective relies on probabilistic information...
Transmission of the same information signal simultaneously over multiple physical layers, such as powerline and unlicensed wireless communication networks, results in higher reliability and/or enhances the coverage range compared to using a single physical layer due to diversity gains. However, each physical layer suffers from its own distinct impairments that can severely degrade performance. Unlicensed...
Effectiveness of an underwater sensor network depends on the number of operating nodes, energy efficiency, and the lifetime of the network. So, the number of active nodes plays a vital role in system performance. But, in underwater harsh environment the number of operating nodes vary frequently with time due to various artificial and natural reasons (for example, failure of some nodes, some could...
The Nakagami-m fading is well known in characterizing the envelop distribution in diverse wireless fading channels, and an accurate estimation of the m parameter is very crucial to evaluate the fading channel capacity. In this paper, we develop a hardware framework implanted in FPGA with corresponding interface design for the m parameter estimation of the Nakagami-m fading channel. Owing to the advantages...
Cooperative wireless communication is a hot research area for attaining diversity through virtual antenna array that is formed by sharing resources among different users.Different strategies of resource utilization such as amplify-and-forward (AF) and decode-and-forward (DF) already exist in cooperative networks.Although the implementation of these strategies is simple, their utilization of the channel...
In this paper, we present an alternative to the enhancement of urban microcellular wireless localization based on aggregate received range and signal power along with the proposed partitioned NLOS bias models. Specifically, we preprocess received measurements as validated measurements and propose a state-space system framework which covers validated NLOS biases by Markov-transitioned multiple models...
In this paper, a p-norm-like constraint is utilized to develop a sparse least mean fourth algorithm for sparse channel estimation. By incorporating the p-norm-like constraint into the cost function of conventional least mean fourth (LMF) algorithm, a p-norm-like constraint least mean fourth (PNC-LMF) algorithm is achieved to exploit the sparsity property of the broadband sparse wireless communication...
Time-based Wireless Local Area Network (WLAN) positioning, particularly in indoor environments, faces the challenge that Non-Line-of-Sight (NLOS) signals enlarge the measured value of Time-of-Flight (TOF) and lead to positioning errors. It is feasible to improve the performance of time-based positioning by recognizing and eliminating NLOS signals. Unfortunately, existing NLOS recognition approaches...
We describe a system developed for the DARPA Wireless Network Defense (WND) program for detecting attacks against the control plane at the link and network layers in a mobile ad hoc network. The goal of our system is for each node to independently assess the trustworthiness of other nodes in its neighborhood, and to disseminate these assessments to other nodes. We have developed a cross-layer invariant-based...
This paper investigates the Doppler shift estimation problem for high speed railway (HSR) wireless communication systems with massive linear receiving antennas. Firstly, a theoretical channel model is built up with channel coefficient, direction of arrival (DOA) and Doppler shift taken into account. Secondly, a new Doppler shift estimation algorithm is proposed through reconstructing the received...
In order to provide a reliable reception and decrease the packet retransmission, the wireless communication system should guaranty the accuracy of channel estimation. This implies that the channel estimation mean-square error (MSE) of the mobile terminals with various speeds should remain lower than a threshold. This usually causes higher pilot overhead in terms of more bandwidth and transmit power...
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