a modem converts digital data into analog signals and vice versa

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... Telecommunications, Winter 2000 Lecture-22 Digital Transmission Digital Transmission of Analog Data (Baseband Transmission): ã Analog voice data must be translated into a series of binary digits ... transmission of analog information represents a basic application of digital communications. Sampling: ã It is an operation that is basic to digital signal processing and digital communication. ... taken. These 8000 samples are then transmitted as a serial stream of 0s and 1s. Now a days all of the trunk lines are digital. So, the analog signals are digitized in the end office by a...

Ngày tải lên: 09/12/2013, 16:15

... [ Team LiB ] Recipe 2.1 Retrieving Hierarchical Data into a DataSet Problem You want to fill a DataSet with parent and related child data, even if the DataSet already has a schema that ... System.EventArgs e) { // Remove all data from the DataSet and refresh the grid. ds.Clear( ); dataGrid.Refresh( ); // Create parent and child data adapters. SqlDataAdapter daParent = new SqlDataAdapter("SELECT ... parent table, Orders, is bound to a data grid on the form. Load DataSet Button.Click Starts by clearing the data from the DataSet and refreshing the data grid. DataAdapter objects are created...

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Ngày tải lên: 29/09/2013, 20:20

... string expression. Add the DataColumn to the parent DataTable. Generate a DataTable from a DataView Create the original DataTable. Create a new DataView instance, passing the DataTable object to ... the DataRowView instance. Creating a DataView To create a DataView from a DataTable, pass the table to the DataView constructor. C# DataView someView = new DataView(someTable); Visual Basic Dim ... associated with each row in a parent table Create parent and child DataTable objects. Add the tables to a DataSet instance. Link the tables with a DataRelation object. Create a string containing...

Ngày tải lên: 03/10/2013, 00:20

... plot(x,log10(PEask),'r.'); grid on; zoom on; title('PE v/s SNR curves for Base band and ASK signals& apos;); xlabel('SNR in db');ylabel('PE'); legend('- For Base ... For Base band','. for ASK'); 0 5 10 15 20 25 30 -300 -250 -200 -150 -100 -50 0 PE v/s SNR curves for Base band and ASK signals SNR in db PE - For Base band . for ASK Page 2 Purpose: ... connected according to the schematic shown. A silicon diode and a 50-ohm terminator are also used. The VCO generates a 20 kHz carrier signal and receiver reference. The summer and variable power...

Ngày tải lên: 19/10/2013, 17:15

... represent binary data. For example, a frequency of 2000 Hz may represent a binary 1 (mark) and 1000 Hz a binary 0 (space). The energy of the signal alternates between the mark and space frequencies ... digital message. FSK describes the modulation of a carrier (or two carriers) by using a different frequency for a 1 or 0. The resultant modulated signal may be regarded as the sum of two amplitude ... output of the digital summer as well as that of the Digital Signal Source was observed on the oscilloscope. The graphs are as shown. It is seen that there is no change in the output signal when f 1 ...

Ngày tải lên: 23/10/2013, 15:15

... Design for Data Requirements Module 8: Designing Data Services Module 9: Data Storage Considerations Designing Data Services and Data Models Investigation Process Data Requirements Activity 3.1: ... is directly traceable to an actor and an object within a use case. Nonfunctional data requirements A nonfunctional data requirement more completely describes a functional data requirement. ... verification Data requirement validation ensures that specified business wants, needs, and constraints are satisfied. " After data requirements are defined, ensuring that they are traceable...

Ngày tải lên: 10/12/2013, 17:15

... pixels may appear many times, and in an audio file, a string of audio samples may also appear repeatedly. A dictionary-based method maintains a dictionary that contains bits and pieces of the data. As ... into two parts, data that has been compressed (this is kept in a data structure called the dictionary) and data that still has to be input and compressed. Assume that the latter part starts with ... alfeastmaneasilyyells A| AAAAAAAAAA AAAAAH . The encoder creates the token (1,9 ,A) , matching the first nine copies of A in the look- ahead buffer and including the tenth A. This is why, in principle, the length of a...

Ngày tải lên: 14/12/2013, 15:15

... the telephone) was given to Alexander Graham Bell. Bain’s fax machine transmitter scanned a flat, electrically conductive metal surface with a stylus mounted on a pendulum that was powered by an electromagnet. ... is an array of variable-size strings. It turns out that a trie is an ideal data structure for a practical implementation of such a dictionary. The first step in understanding such an implementation ... information theory and signal analysis courses. Huffman developed his celebrated algorithm as a term paper that he wrote in lieu of taking a final examination in an information theory class he took at...

Ngày tải lên: 14/12/2013, 15:15

... case of many grayscales) or three components (in the case of a color image). A continuous-tone image is normally a natural image (natural as opposed to artificial) and is obtained by taking a photograph ... watermark. 152 5. Image Compression 5.3 Image Transforms The mathematical technique of a transform is a powerful tool that is employed in many areas and can also serve as an approach to image ... searching for the farthest array element to the left of a 9 that has a count smaller than that of a 9 . This search can be a straight linear search if the array is short enough, or a binary search...

Ngày tải lên: 14/12/2013, 15:15

... warm and cause a picture to appear larger and closer than it really is. Other colors—such as blue, violet, and green—are associated with cool things (air, sky, water, ice) and are therefore called ... Icelandic sagas. However, I once heard that the following simple game may be considered Canada’s na- tional game. Two players start with a set of 15 matches (they don’t have to be smokers) and take ... called the Haar measure, which allows an analog of Lebesgue integrals to be defined on locally compact topological groups. Mathematical lore has it that John von Neumann tried to discourage Haar...

Ngày tải lên: 14/12/2013, 15:15

... came. —Tom Clancy, Clear and Present Danger Chapter Summary Images are an important type of digital multimedia data. Images are popular, they are easy to create (by a digital camera, scanning a document, ... num- bers, as their name implies, are named after Leonardo Fibonacci and have many interesting and beautiful properties and many useful applications. The first two Fibonacci numbers are 1, and any other ... the audio samples. Consecutive audio samples may become larger and larger and be followed by smaller and smaller samples. It therefore makes sense to assume that an audio sample is related in a...

Ngày tải lên: 14/12/2013, 15:15