Title :
Reduced complexity equalization schemes for zero padded OFDM systems
Author :
Shankar, M. R. Bhavani ; Hari, K.V.S.
Author_Institution :
Dept. of Electr. Commun. Eng., Indian Inst. of Sci., Bangalore, India
Abstract :
Three reduced complexity equalization schemes for Zero-padded OFDM systems are described. These schemes guarantee Zero-Forcing (ZF) equalization irrespective of the channel s. Two of these schemes implement the minimum-norm ZF equalizer efficiently using QR decomposition. In the third scheme, the channel zeros are grouped as being inside or outside or on the unit circle. These groups are then equalized sequentially in a manner so as to tackle excess noise amplification. The three schemes are compared for their computational complexity and Bit Error Rate (BER) performance. It is shown that the attractive scheme depends on the system specifications. The BERComputations trade off occurring in the choice of the right algorithm is also highlighted.
Keywords :
OFDM modulation; computational complexity; equalisers; error statistics; BER; QR decomposition; bit error rate; channel zeros; computational complexity; excess noise amplification; minimum-norm ZF equalizer; reduced complexity equalization schemes; zero padded OFDM systems; zero-forcing equalization; Additive white noise; Baseband; Bit error rate; Computational complexity; Equalizers; Helium; Least squares methods; Matrix decomposition; OFDM; Transfer functions; Minimum–maximum phase; OFDM; Orthogonal Frequency Division Multiplexing; Toeplitz matrices; pseudo-inverse; zero padding;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2004.833491