We simulate uncoded BER of BPSK modulated
data as a function of SNR
-in an AWGN channel
-in a Rayleigh fading channel
-in an AWGN channel when direct sequence spreading
is used
and compare results to the theoretical ones.
We assume coherent receiver and perfect
synchronization.
SPREAD SPECTRUM MODULATION TECHNIQUES
-spread spectrum - those modulation methods that are producing a signal whose
spectrum is more wider than of the data signal, the occupied frequency band being
independent by the signal of data band.
-The signals with spread spectrum of direct sequence type BPSK (BPSK-DS-SS)
-The signals with spread spectrum of direct sequence type QPSK – DS–SS
- Frequency hopping spread spectrum signals (FH-SS)
This example program is the source code for the FT232BM Test Application from our Utilities page.
It can be used to test the handshaking lines on FT232BM based RS232/RS485/RS422 designs. This program can also be used for programming the external EEPROM over USB in a manufacturing environment. The test features require the test cable shown on ST_232_245.pdf to be connected.
Our D2XX direct drivers should be installed for this application. The code can be modified to fit your requirements.
To download the application source code , click here.
To download the test cable specification, click here.
this code is a implementation of the Discrete cosinuss transformation.
In this code I have used the direct méthode of calcul by used the equation without used the maatrix multiplication.
Universal.Data.Access.Components 2.50
Universal Data Access Components (UniDAC) is a library of components that provides direct access to most popular database servers from Delphi, Delphi for .NET and, C++Builder. UniDAC can work with such servers as Oracle, Microsoft SQL Server, MySQL, Interbase, Firebird. The UniDAC library is designed to help programmers develop faster and cleaner cross-database applications. UniDAC is a complete replacement for such standard universal technology as dbExpress. UniDAC is a handy in use and efficient data access solution bringing into play many features specific to each server.
模擬器提供了一個(gè)簡(jiǎn)單易用的平臺(tái)，實(shí)施application-layer/P2P協(xié)議和測(cè)試的大型網(wǎng)絡(luò)。在此，已經(jīng)實(shí)現(xiàn)三個(gè)應(yīng)用層組播協(xié)議仿真：
Sequence of direct unicasts
Narada
NICE
In 揚(yáng)erformance of multi-carrier DS CDMA Systems?we apply a multi-carrier signaling technique to a direct-sequence CDMA system, where a data sequence multiplied by a spreading sequence modulates multiple carriers, rather than a single carrier. The receiver provides a correlator for each carrier, and the outputs of the correlators are combined with a maximal-ratio combiner. This type of signaling has the desirable properties of exhibiting a narrowband interference suppression effect, along with robustness to fading, without requiring the use of either an explicit RAKE structure or an interference suppression filter.
