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The huge data traffic demand is a challenge for the next generation of wireless network. Since the majority of data is public information, a novel wireless intelligent pushing mechanism is presented by pushing public information in the way of point to multipoint (P2M) in network idle time, using limited spectrum. Analytic Hierarchy Process (AHP) is employed to establish the performance evaluation...
Nowadays, multi-hop communication systems are often applied in power transmission system to transmit surveillance information to control center. In order to transmit surveillance data more efficiently, it is required to design the communication system with low latency and high reliability. This paper provides a novel data transmission framework along with a QoS provisioning multi-hop routing scheme...
Obtaining the accurate estimation of available bandwidth is precondition of QoS-guaranteed. In this paper, we proposed a novel available bandwidth estimation mechanism in 802.11 RTS/CTS by correct measurements of 1) a new coefficient, called channel utilization ratio, which considering the QoS of realtime multimedia, 2) overhead by the control messaging. Simulation result shows that taking the channel...
Two-way co-channel communication enabled by recent full-duplex (FD) transceiver designs offers the potential to double spectral efficiency. However, currently most of FD radios require additional antennas to facilitate the multi-stage self-interference cancellation (SIC). As increasing antenna number of transceiver certainly leads to higher theoretical link capacities, the real gain of FD systems...
In ad hoc networks, the unused spectrum resources can be effectively sensed by cognitive radio technology, and transmission performance will be improved. Cooperative spectrum sensing is necessary because a single node cannot detect the existence of primary user accurately due to shadowing, noise and fading in wireless channels. Gradient based cooperative sensing (GBCS) is a widely used scheme in distributed...
Herein, we propose a distributed channel allocation scheme for power distribution wireless communication systems in smart grid. By defining the priority for each user equipment(UE), the wireless channels are allocated for each interrupted UE efficiently. Since the UEs obtain their priorities based on the local information, the proposed channel allocation scheme is scalable, and therefore suitable...
A reverse transmission mechanism for smart grid is introduced, in which the transmission robustness of ad-hoc netsegment is guaranteed. The goal is to address the deadlock issue caused by the broken down of the targeted tower, and to reduce transmission power consumption. Performance analysis of the new mechanism is presented, in which the configuration of different number of electrical towers is...
A reverse transmission mechanism for smart grid is introduced, in which the transmission robustness of ad-hoc net-segment is guaranteed. The goal is to address the deadlock issue caused by the broken down of the targeted tower, and to reduce transmission power consumption. Performance analysis of the new mechanism is presented, in which the configuration of different number of electrical towers is...
There are large number of UEs (User Equipment) in the wireless communication networks for power distribution in smart grid with external interference. Based on cluster and sub-band hopping, a fast scheduling mechanism is proposed in this paper. All UEs in the cluster are assigned to the RBs (Resource Block) with fixed relative position in the sub-band, and their working channels are switched according...
A distributed wireless channel allocation mechanism is introduced in this paper. Wireless channel can be allocated to the interrupted UE in a distributed way with a dynamic priority. This allocation scheme is scalable for deployment in large networks as only with the localized information. Moreover, the performance of our allocation scheme is demonstrated by the numerical simulations.
User equipment (UE) as a basic device in cellular, may outfit different type of sensor module for specified usage, called multimode UE. With the natural mobility characteristics, this new type of UE is similar to an enhanced type of mobile sensor, with more energy and more flexibility. Since WSN can be deployed easily as no major infrastructure and human control are needed, the integration of cellular...
Herein, we propose a novel resilient forwarding mechanism to address the contradictory problem between transmission performance and power saving problems. Through automatic backup and transmission line switch, self-healing and autonomous troubleshooting can be achieved for online monitoring in transmission grid. Autonomous surveillance transmission network can be achieved through transmission line...
In this article, we first propose a reverse sector mechanism and an optimization division mechanism, which can provide enormous energy conservation benefits. Based on these mechanisms, an efficient sensory data collection mechanism over a cellular-WSN integrated network, named beacon routing algorithm, is proposed to spontaneously renew the local WSN topology according to the position of the UE relative...
Due to the independent design and development and the unexpected dynamics during deployment of co-existing networks and devices, the limited frequency spectrum will be extremely crowded for wireless sensor networks. Cognitive radio is an efficient approach for the opportunistic use of under-utilized spectrum since they are able to sense the spectrum and use frequency bands if no other user is detected...
In order to decrease implementation complexity, a method which can effectively reduce the peak-to-average power ratio (PAPR) of the WiMAX system is proposed. We firstly oversample the WiMAX system, then normalize, finally clip and filter the signals. Improvements on PAPR reduction, out-of-band radiation and bit error rate performances are discussed in this paper. Simulation results show that the proposed...
In this paper, we investigate efficient and linear bit and power allocation algorithms with proportional fairness among users in downlink OFDM transmission. The objective is to minimize the total transmit power while satisfying the rate requirement and BER constraint of each user. To relieve heavy computational burden, bit loading and power allocation is performed after subcarrier allocation. Proportional...
The adaptive frequency domain interference cancellation and channel equalizer for MIMO-CP-CDMA systems is proposed to cancel the residual interference stage by stage. At each stage, the proposed scheme performs the adaptive forward filtering and interference cancellation in frequency domain so that the signal to interference plus noise ratio can be improved and the error propagation of the interference...
In this paper, we propose a new and rather simple grouped-subcarrier allocation algorithms with proportional fairness among users in downlink OFDM transmission. The proposed algorithm tries to minimize the required transmit power while satisfying the rate requirement and BER constraint of each user. Subcarrier and power allocation are performed in two steps. We are mainly focusing on the subcarrier...
Closed-form expression for the probability density function of output signal-to-noise ratio of macroscopic maximal ratio combiner are derived by means of moment generating function and Gauss-Hermite quadrature, then outage performance is analyzed for different parameter schemes over Nakagami-Lognormal composite fading channels. The theoretical expressions are validated by numerical results. The results...
This paper presents a concatenated maximum-likelihood (ML) decoder for space-frequency block coded orthogonal frequency division multiplexing (SFBC-OFDM) systems in severe frequency selective fading channels. The variation of subchannels during a codeword frame will cause the inter-transmit-antenna interference (ITAI), and reduce the diversity gain for SFBC-OFDM systems. The proposed decoder can eliminate...
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