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.
Carrier-phase synchronization can be approached in a
general manner by estimating the multiplicative distortion (MD) to which
a baseband received signal in an RF or coherent optical transmission
system is subjected. This paper presents a unified modeling and
estimation of the MD in finite-alphabet digital communication systems. A
simple form of MD is the camer phase exp GO) which has to be estimated
and compensated for in a coherent receiver. A more general case with
fading must, however, allow for amplitude as well as phase variations of
the MD.
We assume a state-variable model for the MD and generally obtain a
nonlinear estimation problem with additional randomly-varying system
parameters such as received signal power, frequency offset, and Doppler
spread. An extended Kalman filter is then applied as a near-optimal
solution to the adaptive MD and channel parameter estimation problem.
Examples are given to show the use and some advantages of this scheme.
In this paper, a new family of Cassinian wave-guides
is proposed, simulating and calculation are finished with CST
Microwave Studio that based on Finite Integral Technique (FIT),
and some results are given. Electromagnetic field mode type of it
is TE, electromagnetic field is stronger near neck region, and
some resonance frequencies appear. The new Cassinian curve
wave-guides will possess higher power than ones of the
rectangular and elliptic wave-guides because the height at the
position where maximal electric field occurs is smaller.
FIST可堆疊文件系統,linux文件系統修改相關的開源軟件,使得對linux文件系統功能的改進很簡單了
The FiST (File System Translator) system combines two methods to solve the above problems in a novel way: a set of stackable file system templates for each operating system, and a high-level language that can describe stackable file systems in a cross-platform portable fashion. Using FiST, stackable file systems need only be described once. FiST s code generation tool, fistgen, compiles a single file system description into loadable kernel modules for several operating systems (currently Solaris, Linux, and FreeBSD). The project demonstrates that with FiST, code size and development time are reduced significantly, while imposing a small performance overhead of only 1-2%. These benefits are achieved, as well as portability, without changing existing operating systems or file system.
hanks for downloading this code. This VB Project shows you how to make forms with "rounded rectangle" shape. It also shows you how you can reduce the size of your programs with a GUI by using blocks of images and absolutely positioning and stretching them to create a dialog box, rather than making the whole dialog box in a graphics program and setting it as the Picture property of the Form. Another advantage of using image blocks is that you can resize this form to virtually any size and the effect will still be the same.
Make a graph from database record and either send it to a printer
directly selecting many print options or copy it in any file on disc.
This project also gives you print preview option for A4 size paper and
you can set your graph anywhere on the page.Also if you want to change
graph s height or width you can change.Zooming effect is also given
using hsrollbar.
Using Gaussian elimination to solve linear equations.
// In this version, we allow matrix of any size. This is done by treating
// the name of a 2-dimensional array as pointer to the beginning of the
// array. This makes use of the fact that arrays in C are stored in
// row-major order.
Express DSP compliant C55x DTMF detector software is proposed in two versions: one with a 5 ms frame
size and one with a 10 ms frame size. The versions are quite similar in behavior. The version with a 10 ms
frame size is faster, but the overall quality is higher in the 5 ms version, due to lower time granularity. DTMF算法for TI DSP 54X/55X
Jpeg2000編解碼器,附VC、Delphi等常用編程語言的使用例程
J2K-Codec ver 1.9
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Make your graphics look better with an easy-to-use
JPEG 2000 decoding component. J2K-Codec can help
game developers, screensaver creators and many
others to improve their products--to achieve better
image quality and reduce installation package size.
The new image compression standard based on wavelet
technology has many interesting features not
available in the old JPEG, such as alpha-channel
and varied resolution levels.