4G MOBILE COMMUNICATION
SDC-06 Multi Carrier DS-CDMA System
Objective:
To implement the Multi carrier DS CDMA System using TMS320CV6713.
Project Description: The input data is taken from different users .The PN sequences used for encoding the data for security purpose. Each user having different PN sequences. The User data is scrambled with PN sequences and given as input for Modulator. The 16-PSK (M-ary PSK) Modulation technique is implemented in Modulator. In 16-PSK Modulation, only 16 sub carriers are enough to modulate the encrypted data for all users. The Band width efficiency is achieved through 16-PSK Modulation. The data is transmitted through DSSS concept. In receiver module, the data is received through demodulator and decoder.
BLOCK DIAGRAM:
TRANSMITTER
.... …
… …
RECEIVER:
… ….
IMPLEMENTATION
Transmitter & Receiver
1. The data to be transmitted through the channel is obtained from PC as ASCII.
2. The data is encoded using pseudorandom noise to obtain the DSSS signal.
3. The encoded data is modulated using 16-PSK (M-ary PSK) to assign multiple sub carriers.
4. The IFFT transform generates the time domain modulated signal for transmission at the transmitter output. The output is observed using CRO & PC graphical mode.
5. In the receiver FFT transform is performed to obtain the modulated data bits
6. The modulated data bits are demodulated and decrypted using the known
Pseudo random sequence.
7. The decrypted data bits are converted to character and displayed in the PC.
Fading
1. Fading channel is modeled as a Gaussian random process.
2. The transmitter output is convolved with fading channel to obtain the faded output.
3. The faded output retains the characteristics of the original signal but highly attenuated.
The faded output and the original output can be observed using CRO.
Objective:
To implement the Multi carrier DS CDMA System using TMS320CV6713.
Project Description: The input data is taken from different users .The PN sequences used for encoding the data for security purpose. Each user having different PN sequences. The User data is scrambled with PN sequences and given as input for Modulator. The 16-PSK (M-ary PSK) Modulation technique is implemented in Modulator. In 16-PSK Modulation, only 16 sub carriers are enough to modulate the encrypted data for all users. The Band width efficiency is achieved through 16-PSK Modulation. The data is transmitted through DSSS concept. In receiver module, the data is received through demodulator and decoder.
BLOCK DIAGRAM:
TRANSMITTER
.... …
… …
RECEIVER:
… ….
IMPLEMENTATION
Transmitter & Receiver
1. The data to be transmitted through the channel is obtained from PC as ASCII.
2. The data is encoded using pseudorandom noise to obtain the DSSS signal.
3. The encoded data is modulated using 16-PSK (M-ary PSK) to assign multiple sub carriers.
4. The IFFT transform generates the time domain modulated signal for transmission at the transmitter output. The output is observed using CRO & PC graphical mode.
5. In the receiver FFT transform is performed to obtain the modulated data bits
6. The modulated data bits are demodulated and decrypted using the known
Pseudo random sequence.
7. The decrypted data bits are converted to character and displayed in the PC.
Fading
1. Fading channel is modeled as a Gaussian random process.
2. The transmitter output is convolved with fading channel to obtain the faded output.
3. The faded output retains the characteristics of the original signal but highly attenuated.
The faded output and the original output can be observed using CRO.