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Mathematics and probability for communication engineers
標簽：
communication
Mathematics
probability
engineers
上傳時間：
2013-12-14
上傳用戶：cainaifa
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Many good textbooks exist on probability and random processes written at the under-
graduate level to the research level. However, there is no one handy and ready book
that explains most of the essential topics, such as random variables and most of their
frequently used discrete and continuous probability distribution functions; moments,
transformation, and convergences of random variables; characteristic and generating
functions; estimation theory and the associated orthogonality principle; vector random
variables; random processes and their autocovariance and cross-covariance functions; sta-
tionarity concepts; and random processes through linear systems and the associated
Wiener and Kalman filters.
標簽：
probability
Processes
Random
and
上傳時間：
2020-05-31
上傳用戶：shancjb
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同步技術是跳頻通信系統的關鍵技術之一，尤其是在快速跳頻通信系統中，常規跳頻通信通過同步字頭攜帶相關碼的方法來實現同步，但對于快跳頻來說，由于是一跳或者多跳傳輸一個調制符號，難以攜帶相關碼。對此引入雙跳頻圖案方法，提出了一種適用于快速跳頻通信系統的同步方案。采用短碼攜帶同步信息，克服了快速跳頻難以攜帶相關碼的困難。分析了同步性能，仿真結果表明該方案同步時間短、虛警概率低、捕獲概率高，同步性能可靠。
Abstract:
Synchronization is one of the key techniques to frequency-hopping communication system， especially in the fast frequency hopping communication system. In conventional frequency hopping communication systems， synchronization can be achieved by synchronization-head which can be used to carry the synchronization information， but for the fast frequency hopping， Because modulation symbol is transmitted by per hop or multi-hop， it is difficult to carry the correlation code. For the limitation of fast frequency hopping in carrying correlation code， a fast frequency-hopping synchronization scheme with two hopping patterns is proposed. The synchronization information is carried by short code， which overcomes the difficulty of correlation code transmission in fast frequency-hopping. The performance of the scheme is analyzed， and simulation results show that the scheme has the advantages of shorter synchronization time， lower probability of false alarm， higher probability of capture and more reliable of synchronization.
標簽：
快速跳頻
同步技術
通信系統
上傳時間：
2013-11-23
上傳用戶：mpquest
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bayeserr - Computes the Bayesian risk for optimal classifier.
％ bayescln - Classifier based on Bayes decision rule for Gaussians.
％ bayesnd - Discrim. function, dichotomy, max aposteriori probability.
％ bhattach - Bhattacharya s upper limit of mean class. error.
％ pbayescln - Plots discriminat function of Bayes classifier.
標簽：
Classifier
classifier
bayeserr
Computes
上傳時間：
2015-06-14
上傳用戶：sunjet
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HMM(Hidden Markov Model)，狀態數目N=3，觀察符號數目M=2，時間長度T=3。
(a) probability Evaluation: 給定狀態轉換機率A、狀態符號觀察機率B、和起始機率 ，求觀察序列 出現的機率。
(b) Optimal State Sequence: 給定狀態轉換機率A、狀態符號觀察機率B、起始機率 、和觀察序列 ，求一個狀態序列 使得O出現的機率最大。
(c) Parameter Estimation: 給定狀態轉換機率A、狀態符號觀察機率B、起始機率 、和觀察序列 ，求新的A、B、 ，使得O出現的機率最大。
標簽：
Hidden
Markov
Model
HMM
上傳時間：
2014-08-28
上傳用戶：heart520beat
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We address the problem of blind carrier frequency-offset (CFO) estimation in quadrature amplitude modulation,
phase-shift keying, and pulse amplitude modulation
communications systems.We study the performance of a standard
CFO estimate, which consists of first raising the received signal to
the Mth power, where M is an integer depending on the type and
size of the symbol constellation, and then applying the nonlinear
least squares (NLLS) estimation approach. At low signal-to noise
ratio (SNR), the NLLS method fails to provide an accurate CFO
estimate because of the presence of outliers. In this letter, we derive
an approximate closed-form expression for the outlier probability.
This enables us to predict the mean-square error (MSE) on CFO
estimation for all SNR values. For a given SNR, the new results
also give insight into the minimum number of samples required in
the CFO estimation procedure, in order to ensure that the MSE
on estimation is not significantly affected by the outliers.
標簽：
frequency-offset
estimation
quadrature
amplitude
上傳時間：
2014-01-22
上傳用戶：牛布牛
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We present a particle filter construction for a system that exhibits
time-scale separation. The separation of time-scales allows two simplifications
that we exploit: i) The use of the averaging principle for the
dimensional reduction of the system needed to solve for each particle
and ii) the factorization of the transition probability which allows the
Rao-Blackwellization of the filtering step. Both simplifications can be
implemented using the coarse projective integration framework. The
resulting particle filter is faster and has smaller variance than the particle
filter based on the original system. The convergence of the new
particle filter to the analytical filter for the original system is proved
and some numerical results are provided.
標簽：
construction
separation
time-scale
particle
上傳時間：
2016-01-02
上傳用戶：fhzm5658
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The algorm of viterbi. You talk to your friend three days in a row and discover that on the first day he went for a walk, on the second day he went shopping, and on the third day he cleaned his apartment. You have two questions: What is the overall probability of this sequence of observations? And what is the most likely sequence of rainy/sunny days that would explain these observations? The first question is answered by the forward algorithm the second question is answered by the Viterbi algorithm. These two algorithms are structurally so similar (in fact, they are both instances of the same abstract algorithm) that they can be implemented in a single function:
標簽：
discover
viterbi
algorm
friend
上傳時間：
2016-02-16
上傳用戶：xc216
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This project aim was to build wireless software modem for data communication
between two computers using an acoustic interface in the voice frequency range (20Hz–
20,000Hz). The transmitting antenna is a speaker (frequency response of: 90Hz –
20,000Hz) and the receiving antenna is a microphone (frequency response of: 100Hz –
16,000Hz). The test files used as information files were text files.
This goal was attained both in an incoherent scheme and in a coherent scheme.
Build under Matlab code, our modem uses OFDM (orthogonal frequency division
multiplexing) modulation, synchronization by LMS sequence, channel estimation (no
equalizer) via pilot tones. The symbols are either PSK or ASK for a constellation size of
2 or 4. To optimize the probability of error, these symbols were mapped using Gray
mapping.
Report
標簽：
communication
computers
software
wireless
上傳時間：
2014-05-29
上傳用戶：wangdean1101
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GloptiPoly 3: moments, optimization and
semidefinite programming.
Gloptipoly 3 is intended to solve, or at least approximate, the Generalized Problem of
Moments (GPM), an infinite-dimensional optimization problem which can be viewed as
an extension of the classical problem of moments [8]. From a theoretical viewpoint, the
GPM has developments and impact in various areas of mathematics such as algebra,
Fourier analysis, functional analysis, operator theory, probability and statistics, to cite
a few. In addition, and despite a rather simple and short formulation, the GPM has a
large number of important applications in various fields such as optimization, probability,
finance, control, signal processing, chemistry, cristallography, tomography, etc. For an
account of various methodologies as well as some of potential applications, the interested
reader is referred to [1, 2] and the nice collection of papers [5].
標簽：
optimization
semidefinite
programming
GloptiPoly
上傳時間：
2016-06-05
上傳用戶：lgnf
