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As cutting-edge technology, cluster wells can substantially enhance wells production and oil recovery. Rotating Magnet Ranging System (RMRS) is critical technology to ensure precise ranging and accurate interconnecting target of complex structure wells. The magnetic signal of RMRS is a sinusoidal signal of frequency-varying, narrow band, and its intensity attenuates rapidly with cube of the propagation...
A coprime sensor array (CSA) estimates the spatial power spectral density (PSD) of the observed signal by multiplying one conventionally beamformed subarray scanned response with the complex conjugate of the other. This product processor removes the CSA subarray spatial aliasing ambiguities, but has a peak sidelobe higher than the peak sidelobe of a fully populated uniform linear array (ULA). Moreover,...
A multi-pair amplify-and-forward (AF) MIMO system is considered in this paper, in which all source users transmit their information to destination users via a shared relay. With the large N regime, the effect of small-scale fading tends to diminish while the large-scale fading plays a main role in affecting the system performance. The large-scale fading is modeled as generalized-K fading. While the...
This paper aims at improving the energy efficiency of small cell networks via cell sleep mechanism. The traditional power consumption minimization problem with quality of service (QoS) constraints is reestablished from the distributed small cell eNodeB (SeNB) sleep algorithm. The proposed algorithm consists of a Rate- based Access and Scheduling (RAS) algorithm and a distributed Diluted Load based...
We have proved that restoring the instantaneous amplitude as well as instantaneous phase on Gammatone interbank plays a significant role for speech enhancement. However, it is still challenging topic with dereverberation since previously proposed scheme can only work in noisy environments. In this paper, we extend our previously proposed scheme to be general speech enhancement of removing the effects...
In order to improve network performance and cell-edge UE experience, a study item (SI) on "LTE coverage enhancements" has been proposed and approved for LTE-Advanced. In this SI, it was concluded that the coverage of medium data rate PUSCH (Physical uplink shared channel) is poorer than other LTE channels, with significant gap observed. Therefore, coverage improvement for medium data rate...
In this paper we study a transmission power-tune/control problem in the context of 802.11 Wireless Local Area Networks (WLANs) with multiple (and possibly densely deployed) access points (APs). Previous studies on power control tend to focus on one aspect of the control, either its effect on transmission capacity (PHY layer) assuming simultaneous transmissions, or its effect on contention order (MAC...
One open problem for wireless communication in the high-speed railway environment is channel capacity. In this paper, we study the problem of ergodic capacity for the time-selective and frequency-selective wireless channels in the high-speed railway environment. Firstly, we build up the channel model for the wireless communication between mobile users on the high-speed train and the base station along...
Heterogeneous Network (HetNet) has been extensively discussed as a solution to increase the capacity of Long Term Evolution-Advanced (LTE-A) systems, which coexist of high power macro base stations (BS) and Low Power Nodes (LPNs) such as pico, femto and relay nodes. This paper focuses on the co-channel deployment of macro and pico cells, in which high spectrum reuse and co-channel interference coexist...
There has been an increasing investigation in distributed radar sensor network (RSN) and MIMO-RSN, including waveform design, antenna strategy and spacetime coding, etc. However, distributed-RSN and MIMO-RSN are more like two parallel paths other than one research field in current literature. In this paper, we address the comparison between distributed-RSN and MIMO-RSN for target detection. We first...
This paper considers wireless sensor networks with limited bandwidth, where sensors must transmit sensing results that are distorted with noise uncertainty, to the fusion center reliably and efficiently. A class of rate-1 linear complex-field coding (CFC) transmission strategy is developed, to effectively protect the noisy observation of the signals without any bandwidth expansion. Pairwise error...
Subspace methods have been widely used in blind channel estimation of MIMO-OFDM system. However, direct subspace decomposition suffers from heavy computation complexity of o(N)³. In this paper, a new data projection method (DPM) based principal and minor subspace tracking algorithm is presented by exploiting a novel orthonormalization matrix. The new algorithm exhibits good numerical stability and...
In this paper, an iterative channel estimation algorithm is considered in LTE systems. A simplified expectation maximization (EM) based algorithm is proposed for channel estimation in the frequency domain. In order to deal with “null” sub-carriers in the guard band and make the algorithm simpler, the truncated singular value decomposition method is integrated to EM (TSVD-EM). Together with a simple...
Considering a cooperative multicast system where 2 sources transmit data to 2 users with the help of 1 relay (2-1-2), the performance of a network coded cooperative (NCC)transmission scheme is evaluated. Due to the use of network coding, more than one source node can be served simultaneously by one cooperative transmission. As a result, the time resource consumed by the cooperative transmission is...
In a ΔΣ modulator design process, the amplifier nonlinearity problem is usually neglected. However, nonlinearity problems will seriously affect the signal to noise ratio, but rarely discussed in literatures. In this paper, we model the problem and elaborate the importance of the coefficient selected. We design a folded-cascode op-amp with source-degeneration to suppress nonlinearity. The PSD analysis...
MIMO (Multiple-Input-Multiple-Output) is a promising structure for wireless communication. While virtual MIMO structure has been proposed for distributed and cooperative wireless networks, this proposed structure has also put additional energy consumption where energy stands in the important position. At the same time, we have observed that this-problem-caused low energy nodes' mibehavior will degrade...
An update dynamic programming algorithm is presented in allusion to the features of the moving infrared small dim target. The main idea of this algorithm is that the predicting states between frames and a low threshold are applied to reduce the computation. The background noise is suppressed by the image pre-processing. The probability of detecting and false alarm are used to determine the threshold...
In current multi-hop relay networks (MRNs), normally the communication path is not optimized, especially when two mobile stations (MSs) attached to the same relay station (RS) need to communicate with each other. In this paper, a novel data transmission scheme: administrable and controllable local forwarding for OFDMA-TDD based two-hop relay cellular networks, is proposed. In the local forwarding...
The conventional cooperative protocols have to face some problems in practical broadcast and multicast systems because feedback channel is unavailable. An adaptive cooperative relay protocol, which can be adopted in future broadcast systems, is proposed in this paper. The outage probability performance of this protocol is analyzed over Nakagami-m fading channel, and the asymptotic expression of outage...
In the conventional multicast transmission scheme the multicast signals are transmitted to a single multicast group in one multicast service and the system capacity is restricted by the worst channel user. We proposed a novel time-division multicast transmission scheme using multiple multicast groups. In this scheme, the signals are transmitted to the inner multicast group within a boundary distance...
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