Title :
Enhancing Data Efficiency in IEEE- 802.11a Using Frequency and Time domain Equalization
Author :
Gangadhar, R.S. ; Vijay, K.C.
Author_Institution :
DA-IICT, Gandhinagar
Abstract :
In this paper, increase in data rate is achieved by removing the cyclic prefix between the OFDM symbols. The intersymbol interference and intercarrier interference caused by the removal of cyclic prefix are removed by equalization. We propose two methods of equalization. In the first method, the zero frequency domain equalization (ZF-FEQ) is done by making use of spill over in the unused carriers. The pre-FFT time domain Equalizer minimizes the noise amplification caused by ZF-FEQ. In the second method, the Inter Symbol Interference and Inter Carrier Interference are removed at the transmitter itself by transmitting data in the unused carriers, which is the combination of data in the used carriers. The requirement of power in the unused carriers increases as the length of the channel increases. Using the TEQ, the effective length of the channel is reduced to minimum. The simulation results are presented in support of these two methods.
Keywords :
OFDM modulation; equalisers; intercarrier interference; intersymbol interference; wireless LAN; IEEE-802.11a; OFDM symbols; cyclic prefix; data efficiency; intercarrier interference; intersymbol interference; noise amplification; preFFT time domain equalizer; time domain equalization; zero frequency domain equalization; Computational complexity; Data models; Delay; Demodulation; Equalizers; Frequency domain analysis; Interchannel interference; Intersymbol interference; OFDM modulation; Transmitters; Cyclic prefix (CP); Data efficiency; Frequency domain equalizer (FEQ); Interchannel interference (ICI); Intersymbol interference (ISI); Time domain equalizer (TEQ);
Conference_Titel :
TENCON 2005 2005 IEEE Region 10
Conference_Location :
Melbourne, Qld.
Print_ISBN :
0-7803-9311-2
DOI :
10.1109/TENCON.2005.300867