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In this paper, we investigate the performance of mobile vehicle positioning based on signal propagation delay estimation in the uplink case for a realistic propagation environment. In order to optimize the ranging performance, we introduce a parametric waveform. This waveform contains a scalar parameter for adjusting the distribution of the available signal power over the frequency. The optimization...
Smartphones and other mobile devices are today pervasive across the globe. As an interesting side effect of the surge in mobile communications, mobile network operators can now easily collect a wealth of high-resolution data on the habits of large user populations. The information extracted from mobile network traffic data is very relevant in the context of population mapping: it provides a tool for...
Chatting with nearby interested strangers instantly in location-based mobile social network (LMSN) has become increasingly popular. Currently, friend recommendation relies only on the simple and limited user profiles, and is agnostic to users' offline behaviors in the real world. For the first time, we focus on utilizing the user's check-in behaviors in the real world, instead of the general acquaintance-based...
In recent years, the prevalence of voice disorders has been increasing dramatically, mainly due to unhealthy lifestyles and voice abuse. An impairment in the ability to produce the sound of the voice is indicated by the medical term Dysphonia. This disorder impacts on the quality of life of the population in general, but especially of professional voice users, like teachers or singers, for whom dysphonia...
The combined use of bilinear and vector rational interpolation for motion field estimation of erroneously received MPEG-2 video bitstreams is reported. Motion vector rational interpolation is capable of adapting its behaviour with respect to neighbouring motion information. Bilinear interpolation, operating on a finer interpolation grid, takes neighbouring spatial correlations into account. Thus,...
If temporal variation of a person's hunger degree could be estimated, it would be possible to adjust his/her eating habits and/or prevent obesity. It is well-known that there is a negative correlation between a hunger degree and a blood glucose level. However, it is hard to measure a person's blood glucose level anytime and anywhere, because it relies usually on an invasive method (e.g., blood sampling)...
The speed of user equipment (UE) is significant in improving the performance of orthogonal frequency division multiplexing (OFDM) systems. Estimating the speed can help in adaptively allocating resources to users, reducing call drop rate in handoff, selecting the optimal radiation pattern, etc. The Doppler spread caused by the relative movement between transmitter and receiver can be utilized to estimate...
Sustaining good quality of service, in mobile systems, is indeed a direct result of the efficient pre - planning process. Accurate path loss prediction and estimation is one important step toward best deployment of such systems. Recently Terrain roughness parameters are considered essential factors in realizing reliable path loss estimation. In this work, the slope (S) of the route undergone by the...
This paper addresses the correlation of fading signal parameters for dual-satellite land mobile satellite (LMS) channels. We use Loo's model to describe the slow and fast variations that occur due to varying shadowing conditions and multipath fading, respectively. Loo's parameters (mean power of direct signal component, standard deviaton of direct signal component, and average multipath power) are...
In this paper we analyze the performance of different channel estimators under different antenna correlation conditions. This analysis is performed for various spatial multiplexing techniques considered in 3GPP Long term evolution (LTE) Release 8 (R8) using extensive simulations. By considering the LTE downlink system parameters and the LTE channel model, we measure the performance of channel estimators...
It is a significant application of wireless sensor networks to monitor a mobile target. Multiple sensor nodes cooperate to get an accurate estimation of the signal of the mobile target. Spatial correlation, induced by the spatial distribution of target and sensor nodes, is an inherent phenomenon of wireless sensor networks. This correlation causes redundancy amongst nodes which create redundant information...
System performance of mobile wireless communications is limited by fast channel variations, which are mostly due to the mobility of user terminals and scatterers. In order to obtain the optimal system performance, precise knowledge of the channel variations is often needed through channel prediction. A new cluster-based time-domain predictor with improved performance is proposed in this paper. Our...
Maximum Doppler spread or, equivalently, the vehicle velocity, can be estimated to improve handoff algorithms and tune parameters for systems when channel conditions change. This paper presents a new mobile station velocity estimator based on the normalized auto-covariance of the Rician fading signal and that of the squared envelope respectively of the received signal. The proposed algorithm is based...
Various terrestrial digital television broadcasting standards have been developed in the last two decades for both fixed residential and mobile receivers. Since personal mobile terminal integrated with multiple functionalities is becoming more popular, it is highly desirable to come up with a universal platform for mobile TV reception which can detect the system parameters of DTV signals automatically...
This paper proposes another technique to forecast Chinese mobile user based on the ARIMA model. There are two major premises to use ARIMA model in mobile user prediction: mobile market is mature and still has big space for development. On the basis of the historical incremental mobile user number from 2002q1 to 2009q4, through model identification and estimation, an ARIMA (1, 1, 2) model is selected...
In Advanced Long Time Evolution (LTE-A) mobile wireless communication system, the Carrier Aggregation (CA) technique feature was introduced to support large transmission bandwidth. But due to the capacity limit of UE, to measure all component carriers with low latency and cost has been a challenge. In this paper a solution is presented in which only some reference component carriers need to be measured;...
The Doppler spread, or evenly, the mobile speed of motion, is an evaluation of the spectral spreading of mobile fading channel. A precise estimation of the mobile speed and/or velocity is of great significance in wireless mobile applications which needs the acquaintance of the rate of the channel variations. In this article we propose the use of the auto-correlation of the in-phase component of the...
This paper mainly studies the demand function of mobile voice service on Chinese communication market. Considering the characteristics of this product, consumption habit is introduced into our model, thus dynamic panel data model and corresponding estimating methods are used to estimate the model. We compare our results with studies done by other researchers, the comparison shows that consumption...
To estimate speed of a moving user transmitting data over a single input single output (SISO) Rayleigh fading channels, many autocorrelation function (ACF) based schemes have been presented in literature. It was shown that in a multiple input multiple output (MIMO) channel with N antennas on each side, the velocity of a moving mobile can be obtained by applying the ACF based velocity estimation schemes...
In linear minimum mean-square error (LMMSE) channel estimation for multicarrier transmission, how to estimate the needed channel correlation function remains a problem for systems with small number of pilots operating in time varying channels. We consider approximating the channel power delay profile by a shape characterized fully by the mean delay and the root-mean-square (RMS) delay spread. We present...
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