[!]keyword value [&& [!]keyword value] begin-script profile finishscript in .NET

Integrating QR-Code in .NET [!]keyword value [&& [!]keyword value] begin-script profile finishscript

To simplify writing expressions in a table or matrix, it is important to provide a name for each group.

Both examples look similar, and they are. It's what happens under the hood that gives us the advantages of structures in VB .NET. You can define a structure as a way to group like data. Structures are declared with the Structure End Structure statement. Between the declarations, you list your variables with the Public, Private, Protected, or Shared scope. Inside of a structure, variables declared with Dim are Public by default; this is the exact opposite behavior in classes and modules. When you declare a variable to be an instance of a structure, all of the structure's members are initialized automatically, which means you do not need to initialize individual members of a structure. When you decide that you need to use the structure, you declare a variable as the type of that structure. You can declare the variable in one of two ways: Dim varname as StructureName Dim varname as StructureName = New StructureName You do not access the structure directly; you create an instance of the structure through a variable. You might say that you could use global variables to accomplish the same thing, and that is true, but there is no grouping of like data in that case. So it is more difficult to manage multiple arrays than possibly a single array stored in a structure. It is also very nice syntax when referencing types within a structure, similar to a property in a class. Another thing to keep in mind is that global variable should be avoided whenever possible. Sharing fields between classes as structures or properties is cleaner and more consistent with OO design. Note Structures are value types, not reference types. After you define a structure, and declare a variable to reference the structure, you can use the following syntax to reference the members of the structure: CCusotmer.strAddress = "1234 Main Street" CCustomer.strName = "Bill Gates" To make your structure more robust, and to give you an idea of how far you can take it, consider this structure, which stores a SQL DataSet, an array of names, and a Word document, and has a method to combine variables defined within the structure. Structure MyData Private strName as string Private strEmail as string Private retVal as string Public dsData as DataSet Public strNames() as string Public Docs as Word.Document Function DoName() as String retVal = strName & strEMail Return retVal End Function End Structure Public Function ProcessMyData(TheData as MyData) as Boolean

h (y)m(F(y))

egrep the message header (default)

Symbols 4-pilot and 12-virtual {ai} PSK, QPSK, c k or QAM Modulator {cki} Serial to 48 Parallel 64-Point IDFT 64-parallel to serial f (t )

-100 800

where is the SNR after the switching device (i.e., the SNR at the RX), 1 is the SNR of the rst antenna, 2 is the SNR of the second antenna, and t is the switching threshold. (a) For Rayleigh fading where both antennas have the same mean SNR, give the cdf and pdf of . (b) If we use mean SNR as our performance measure, what is the optimum switching threshold and resulting mean SNR What is the gain in dB of using switched diversity compared with that of a single antenna Compare this gain with that of maximal ratio combining and selection diversity. (c) If, instead, our performance measure is average BER, what is the optimum switching threshold for binary noncoherent FSK What is the average BER for an SNR of 15 dB Compare this with the case of a single antenna. Remember that the BER for binary noncoherent FSK is 1 exp (30.28) 2 2 10. In maximal ratio combining each branch is weighted with the complex conjugate of that branch s complex fading gain. However, in practice the RX must somehow estimate fading gains in order to multiply received signals by them. Assume that this estimation is based on pilot symbol insertion, in which case the weights become subject to a complex Gaussian error. If an Nr -branch diversity system with Rayleigh fading and a mean SNR on each branch is used, the pdf of the output SNR becomes [Tomiuk et al. 1999] BER = pdf ( ) =