08-02-2013, 12:22 PM
IMPROVING THE PERFORMANCE OF SC-FDMA IN THE PRESENCE OF CFO USING LINEAR PARALLEL INTERFERENCE CANCELLER
1IMPROVING THE PERFORMANCE .pptx (Size: 1.03 MB / Downloads: 34)
OBJECTIVE OF THE PROJECT
The objective of this project is to analyze the performance of SC-FDMA in the presence of carrier frequency offset (CFO) using ‘linear parallel interference canceller’ (LPIC).
The structure of interference is constructed from the analysis using the proposed LPIC in the receiver and it is cancelled from the system to improve the performance of the system.
The proposed algorithm is implemented using MATLAB to show that it improves the performance of the system and restores the diversity provided by the system.
Introduction-Base technologies
There are three base technology choices:
Frequency division multiple access (FDMA)
Time division multiple access (TDMA)
Code division multiple access (CDMA)
FDMA
Simplest
Best suited for analog links
Each station has its own frequency band, separated by guard bands
Receivers tune to the right frequency
Number of frequencies is limited
Reduce transmitter power; reuse frequencies in non-adjacent cells
TDMA
All stations transmit data on same frequency, but at different times
Needs time synchronization
Pros
users can be given different amounts of bandwidth
mobiles can use idle times to determine best base station
can switch off power when not transmitting
Cons
synchronization overhead
greater problems with multipath interference on wireless links
CDMA
Users separated both by time and frequency
Send at a different frequency at each time slot (frequency hopping)
Or, convert a single bit to a code (direct sequence)
receiver can decipher bit by inverse process
Pros
hard to spy
immune from narrowband noise
no need for all stations to synchronize
no hard limit on capacity of a cell
all cells can use all frequencies