These routines model tropospheric radiowave propagation over variable terrain and calculates propagation loss vs. height and range. Propagation loss is displayed in dB contours on a height vs. range plot. TPEM is based on the split-step Fourier PE method and was originally developed from an early PE model called PEPC, written by Fred Tappert. Propagation loss over variable terrain is modeled by shifting the field an appropriate number of bin widths correspondc ing to the height of the ground. The field is determined using the smooth earth PE method.
标签： tropospheric propagation calculates radiowave
上传时间： 2017-01-01
上传用户：225588
observable distribution grid are investigated. A distribution grid is observable if the state of the grid can be fully determined. For the simulations, the modified 34-bus IEEE test feeder is used. The measurements needed for the state estimation are generated by the ladder iterative technique. Two methods for the state estimation are analyzed: Weighted Least Squares and Extended Kalman Filter. Both estimators try to find the most probable state based on the available measurements. The result is that the Kalman filter mostly needs less iterations and calculation time. The disadvantage of the Kalman filter is that it needs some foreknowlegde about the state.
标签： distribution observable grid investigated
上传时间： 2014-12-07
上传用户：ls530720646
In this project we analyze and design the minimum mean-square error (MMSE) multiuser receiver for uniformly quantized synchronous code division multiple access (CDMA) signals in additive white Gaussian noise (AWGN) channels.This project is mainly based on the representation of uniform quantizer by gain plus additive noise model. Based on this model, we derive the weight vector and the output signal-to-interference ratio (SIR) of the MMSE receiver. The effects of quantization on the MMSE receiver performance is characterized in a single parameter named 鈥漞quivalent noise variance鈥? The optimal quantizer stepsize which maximizes the MMSE receiver output SNR is also determined.
标签： mean-square multiuser receiver project
上传时间： 2014-11-21
上传用户：ywqaxiwang
have recently become very interested in the area of genetic algorithms and Ant Colony Optimization techniques. I was determined to write a complete program demonstrating these two techniques. In particular I wanted to compare the efficiency of these two approaches in the area of finding solutions to the Traveling Salesman Problem
标签： Optimization algorithms interested recently
上传时间： 2013-12-20
上传用户：牛布牛
GNU_Radio GNU radio is a free/open-source software toolkit for and the content is controlled by a handful of organizations. Cell building software radios, in which software defines the phones are a great convenience, but the features your phone transmitted waveforms and demodulates the received supports are determined by the operator s interests, not yours. waveforms. Software radio is the technique of getting code A centralized system limits the rate of innovation. Instead of as close to the antenna as possible. It turns radio hardware cell phones being second-class citizens, usable only if problems into software problems.
标签： open-source GNU_Radio software toolkit
上传时间： 2017-06-26
上传用户：拔丝土豆
Pattern-MAC (PMAC) protocol, instead of having fixed sleepwakeups, the sleep-wakeup schedules of the sensor nodes are adaptively determined. The schedules are decided based on a node’s own traffic and that of its neighbors.
标签： sleepwakeups sleep-wakeup Pattern-MAC schedules
上传时间： 2017-08-28
上传用户：cainaifa
Features a unique program to estimate the power spectral density. The spectrum containing all significant details is calculated from a time series model. Model type as well as model order are determined automatically from the data, using statistical criteria. Robust estimation algorithms and order selection criteria are used to obtain reliable results. Unlike in FFT analysis, where the experimenter has to set the amount of smoothing of the raw FFT, the right level of detail is assessed using the data only.
标签： containing Features estimate spectral
上传时间： 2014-02-09
上传用户：daguda
In this paper we present a classifier called bi-density twin support vector machines (BDTWSVMs) for data classification. In the training stage, BDTWSVMs first compute the relative density degrees for all training points using the intra-class graph whose weights are determined by a local scaling heuristic strategy, then optimize a pair of nonparallel hyperplanes through two smaller sized support vector machine (SVM)-typed problems. In the prediction stage, BDTWSVMs assign to the class label depending on the kernel density degree-based distances from each test point to the two hyperplanes. BDTWSVMs not only inherit good properties from twin support vector machines (TWSVMs) but also give good description for data points. The experimental results on toy as well as publicly available datasets indicate that BDTWSVMs compare favorably with classical SVMs and TWSVMs in terms of generalization
标签： recognition Bi-density machines support pattern vector twin for
上传时间： 2019-06-09
上传用户：lyaiqing
Abstract—In the future communication applications, users may obtain their messages that have different importance levels distributively from several available sources, such as distributed storage or even devices belonging to other users. This scenario is the best modeled by the multilevel diversity coding systems (MDCS). To achieve perfect (information-theoretic) secrecy against wiretap channels, this paper investigates the fundamental limits on the secure rate region of the asymmetric MDCS (AMDCS), which include the symmetric case as a special case. Threshold perfect secrecy is added to the AMDCS model. The eavesdropper may have access to any one but not more than one subset of the channels but know nothing about the sources, as long as the size of the subset is not above the security level. The question of whether superposition (source separation) coding is optimal for such an AMDCS with threshold perfect secrecy is answered. A class of secure AMDCS (S-AMDCS) with an arbitrary number of encoders is solved, and it is shown that linear codes are optimal for this class of instances. However, in contrast with the secure symmetric MDCS, superposition is shown to be not optimal for S-AMDCS in general. In addition, necessary conditions on the existence of a secrecy key are determined as a design guideline.
标签： Fundamental Limits Secure Class on of
上传时间： 2020-01-04
上传用户：kddlas
European Research Framework programs are public policy instruments designed to strengthen European competitiveness through cooperation. Although they have a fixed time frame, determined research themes, and a specific expected impact, the achievements in research and development (R&D) made by these funded proj- ects pave the way for a research continuum.
标签： Communications Horizons Wireless Mobile New and in
上传时间： 2020-05-30
上传用户：shancjb
