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The paper studies the theoretical error lower bound of the mobile tracking problem in mixed Line-of-sight (LOS) and non-line-of-sight (NLOS) conditions. A new method is presented to compute the posterior Cramer-Rao lower bound (CRLB): the mobile state is first estimated by decentralized EKF method, then sigma point set and unscented transformation are applied to calculate Fisher information matrix...
To achieve accurate velocity estimation, the Dual EBPSK system model is proposed. EBPSK modulation is high in transmission efficiency. Two independent velocity estimation methods in the Dual EBPSK system are presented. Two velocity estimation results can be fused to get more accurate estimation. The validation of the two methods is proven by following analysis and comparison. Typical error in satellite...
The Near Field Communication (NFC) has become one of most competitive techniques in the field of short distance wireless communication. The existed protocol does not clearly stipulate modulation mode in the high rate. Many kinds of modulation methods are used in the high rate, in which multi-ary modulation can satisfy the demand of high rate, but the high system complexity and the poor BER performance...
A sliding window hybrid quasi Newton algorithm is proposed in this paper for minimum bit error rate nonlinear equalizers online training. Switching between sliding window stochastic gradient algorithm and sliding window quasi Newton algorithm makes the new algorithm be stable and converge fast. Moreover, by modifying the quasi Newton method, the new algorithm can be applied to high-dimensional parameters...
The classical rate distortion (R-D) theories which study the relationship between the coding bit rate and signal distortion have limit in studying the impact of the coding complexity. However, the advanced video coding technology lead to not only high coding efficiency but also the extremely high coding complexity. The high complexity is not suitable for the real time applications and mobile devices...
The Internet Protocol television (IPTV), new revenue-generating services, brings the end user a much more entertainment experience at an affordable cost. The IPTV brings not only the traditional voice and data services but also the new features such as video on demand (VoD), broadcast TV, customized ad insertion, and so on. However, the realization of the IPTV business requires much wider bandwidth,...
Research on anti-fading is an important problem in wireless communication system. The high-efficiency Extended Binary Phase Shift Keying (EBPSK) modulation has very good anti-fading characteristics because of the existing of the guard interval. The EBPSK transmission system is simply introduced firstly. Then the transmission performance of EBPSK signal in fading channel model is analyzed. Simulation...
The classical rate distortion (R-D) theories have been developed to study the relationship between the coding bit rate and signal distortion. However, with the development of the current mobile, wireless, distributed communication and the advanced audio and video coding technology, the constraints of the coding bit rate has become more and more weak while the constraints of the coding complexity has...
The H.264/AVC achieves higher compression efficiency than previous video coding standards. However, the full RD cost calculations for all intra-prediction modes and exhaustive searches for optimal motion vectors for variable block sizes result in extremely high computation complexity, which obstruct it from practical use. In this paper, an efficient algorithm is proposed to reduce the complexity of...
In this paper the geometry of DTV-based passive radar is studied, with the form of the ambiguity function (AF) of the system given to get TDOA and Doppler parameters, and the state and measurement models established. Then the unscented Kalman filter (UKF) method with TDOA/Doppler measurements is presented for target tracking. The simulation results show that the proposed algorithm can effectively...
In order to satisfy the higher and higher demand for communication system and deal with co-frequency interference, throughput efficient wireless system based on Extended Binary Phase Shift Keying (EBPSK) modulation is introduced firstly. On this basis, corresponding transmission scheme with co-frequency interference is also given, meanwhile, the important ultra narrow band filter is presented. Simulation...
In wireless mobile location systems, NLOS problem has been considered as the key issue that affects the estimation accuracy. In this paper, mobile location in a mixed line-of-sight/non-line-of-sight (LOS/NLOS) condition is considered, and a NLOS error mitigation technique is proposed, which utilizes unscented Kalman filter (UKF) to jointly estimate mobile state and the hidden sight state based on...
This paper presents a mobile station (MS) location method using constrained least-squares (CLS) estimation in the non-line-sight (NLOS) conditions. Three or more time-of-arrival (TOA) measurements of a signal traveling between a MS and base stations (BSs) are necessary for its localization. However, when some of the measurements are from NLOS paths, the location errors can be very large. We propose...
An improved Rao-Blackwellized particle filtering (RBPF) is proposed track the mobility of mobile station (MS) in mixed line-of-sight (LOS) or non-line-of-sight (NLOS) conditions in cellular network. The algorithm first estimates the sight condition state using particle filtering method, in which particles are sampled by the optimal trial distribution and selected by one-step backward prediction. Then,...
In this paper, a new bit allocation scheme is proposed for MPEG-4 Advanced Audio Coding. Developed from the generalized BFOS (Breiman, Friedman, Olshen, and Stone) algorithm, the new approach considers adaptive adjustment of quantization step size also, except bit-use efficiency. The basic idea behind our scheme is that every modification of scale factor for each band is determined by the ldquobit...
The micro-Doppler effect on a passive positioning system, introduced by motion of a mobile terminal in multipath fading environment, was investigated and its parameters were estimated. First micro-Doppler model under multipath propagation was presented. In addition micro-Doppler effect induced by non-uniform rectilinear motion of mobile terminal in multipath environment was analyzed. Micro-Doppler...
A novel approach for image registration based on mutual information is presented in this paper. Firstly, normalized mutual information is introduced as the fitness function to supersede the traditional mutual information. Meanwhile, the extrema in fitness function resulted from interpolation is analyzed and the solution is presented as adding a weighted parameter into the variables set. Secondly,...
Shannon's channel capacity equation, a very important theory, defines the maximum transmission rate of communication systems. However, a new communication scheme, named ultra narrow band, is said to "break" Shannon's limit. During the research, a special kind of filters having different signal and noise bandwidth was found, therefore, the aim of our study was to extend Shannon's channel...
Shannon's channel capacity equation, a very important theory, defines the maximum transmission rate of communication systems. However, if we assume that signal bandwidth is larger than noise bandwidth, then the channel capacity is larger than Shannon' limit, which can be proved. This paper presents that geometric feature filter is satisfied with this assumption, therefore, in the frame of information...
This paper focuses on the problem of selecting the optimum network for multicast services in the overlapping coverage of mobile and broadcasting networks. This algorithm considers various factors that impact on the final decisions. It comprises two steps: firstly, an analytic hierarchy process (AHP) method is applied to schedule the service queue according to user preference and different service...
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