Enis Akay | University of California, Irvine (original) (raw)

Papers by Enis Akay

Orthogonal frequency division multiplexing (OFDM) is known as an efficient technique to combat fr... more Orthogonal frequency division multiplexing (OFDM) is known as an efficient technique to combat frequency selective channels. In our earlier work, we showed that the combination of bit interleaved coded modulation (BICM) and OFDM achieves the full frequency diversity offered by a frequency selective channel with equal power delay profile conditioned on the minimum Hamming distance, dfree, of the convolutional code. In Winter 2006, we were able to extend this result to frequency selective channels with any kind of power delay profile. This system has a simple Viterbi decoder with a modified metric.

In the Spring 2006 quarter we investigated BBO, which is a combination of BICM, single beamformin... more In the Spring 2006 quarter we investigated BBO, which is a combination of BICM, single beamforming, and OFDM. We showed that BBO achieves full diversity in space and frequency regardless of the power delay profile (PDP) of the channel. Since only one stream of data is transmitted over all transmit antennas, a simple interleaver is shown to be sufficient to achieve full space and frequency diversity. Simulation results show that beamforming-based systems introduce substantial coding gain, even with partial channel state information at the transmitter (CSIT), when compared to other systems based on space time block codes (STBC) with the same full diversity order. In addition, we show through simulations that reduction of CSIT from full resolution to only one bit per tone results in an SNR reduction of only about 1.5-2 dB.

Antennas and Wireless Propagation Letters, 2006

2007 Information Theory and Applications Workshop, 2007

IEEE Wireless Communications and Networking Conference, 2006. WCNC 2006., 2006

2006 Ieee 63rd Vehicular Technology Conference, May 7, 2006

ó In this paper, we analyze the performance of bit interleaved coded multiple beamforming (BICMB)... more ó In this paper, we analyze the performance of bit interleaved coded multiple beamforming (BICMB). We provide interleaver design criteria such that the resulting system achieves full spatial multiplexing of min(N; M) and full spatial diversity of NM for a system with N transmit and M receive antennas. We combined BICMB with OFDM in order to combat ISI caused by

IEEE International Conference on Communications, 2005. ICC 2005. 2005, 2005

ITA Inaugural Workshop, 2006

Abstract—In this paper, we analyze the performance of bit interleaved coded multiple beamforming ... more Abstract—In this paper, we analyze the performance of bit interleaved coded multiple beamforming (BICMB). We provide interleaver design criteria such that the resulting system achieves full spatial multiplexing of min (N, M) and full spatial diversity of NM for a system ...

IEEE Transactions on Communications, 2006

… and Propagation Society …, 2006

IEEE Transactions on Communications, 2000

Abstract: In this dissertation we show that BICM-OFDM systems can achieve the maximum frequency d... more Abstract: In this dissertation we show that BICM-OFDM systems can achieve the maximum frequency diversity regardless of the power delay profile (PDP) of the frequency selective channel. That is for L-tap frequency selective channels, BICM-OFDM is shown to achieve ...

Ieee Transactions on Communications, Dec 1, 2006

The interleaver design criteria described in [1] should take into account all error patterns of i... more The interleaver design criteria described in [1] should take into account all error patterns of interest.

2004 IEEE International Conference on Communications (IEEE Cat. No.04CH37577), 2004

2004 IEEE 59th Vehicular Technology Conference. VTC 2004-Spring (IEEE Cat. No.04CH37514), 2004

2004 IEEE 59th Vehicular Technology Conference. VTC 2004-Spring (IEEE Cat. No.04CH37514), 2004

IEEE Wireless Communications and Networking Conference, 2006. WCNC 2006., 2006

Orthogonal frequency division multiplexing (OFDM) is known as an efficient technique to combat fr... more Orthogonal frequency division multiplexing (OFDM) is known as an efficient technique to combat frequency selective channels. In our earlier work, we showed that the combination of bit interleaved coded modulation (BICM) and OFDM achieves the full frequency diversity offered by a frequency selective channel with equal power delay profile conditioned on the minimum Hamming distance, dfree, of the convolutional code. In Winter 2006, we were able to extend this result to frequency selective channels with any kind of power delay profile. This system has a simple Viterbi decoder with a modified metric.

In the Spring 2006 quarter we investigated BBO, which is a combination of BICM, single beamformin... more In the Spring 2006 quarter we investigated BBO, which is a combination of BICM, single beamforming, and OFDM. We showed that BBO achieves full diversity in space and frequency regardless of the power delay profile (PDP) of the channel. Since only one stream of data is transmitted over all transmit antennas, a simple interleaver is shown to be sufficient to achieve full space and frequency diversity. Simulation results show that beamforming-based systems introduce substantial coding gain, even with partial channel state information at the transmitter (CSIT), when compared to other systems based on space time block codes (STBC) with the same full diversity order. In addition, we show through simulations that reduction of CSIT from full resolution to only one bit per tone results in an SNR reduction of only about 1.5-2 dB.

Antennas and Wireless Propagation Letters, 2006

2007 Information Theory and Applications Workshop, 2007

IEEE Wireless Communications and Networking Conference, 2006. WCNC 2006., 2006

2006 Ieee 63rd Vehicular Technology Conference, May 7, 2006

ó In this paper, we analyze the performance of bit interleaved coded multiple beamforming (BICMB)... more ó In this paper, we analyze the performance of bit interleaved coded multiple beamforming (BICMB). We provide interleaver design criteria such that the resulting system achieves full spatial multiplexing of min(N; M) and full spatial diversity of NM for a system with N transmit and M receive antennas. We combined BICMB with OFDM in order to combat ISI caused by

IEEE International Conference on Communications, 2005. ICC 2005. 2005, 2005

ITA Inaugural Workshop, 2006

Abstract—In this paper, we analyze the performance of bit interleaved coded multiple beamforming ... more Abstract—In this paper, we analyze the performance of bit interleaved coded multiple beamforming (BICMB). We provide interleaver design criteria such that the resulting system achieves full spatial multiplexing of min (N, M) and full spatial diversity of NM for a system ...

IEEE Transactions on Communications, 2006

… and Propagation Society …, 2006

IEEE Transactions on Communications, 2000

Abstract: In this dissertation we show that BICM-OFDM systems can achieve the maximum frequency d... more Abstract: In this dissertation we show that BICM-OFDM systems can achieve the maximum frequency diversity regardless of the power delay profile (PDP) of the frequency selective channel. That is for L-tap frequency selective channels, BICM-OFDM is shown to achieve ...

Ieee Transactions on Communications, Dec 1, 2006

The interleaver design criteria described in [1] should take into account all error patterns of i... more The interleaver design criteria described in [1] should take into account all error patterns of interest.

2004 IEEE International Conference on Communications (IEEE Cat. No.04CH37577), 2004

2004 IEEE 59th Vehicular Technology Conference. VTC 2004-Spring (IEEE Cat. No.04CH37514), 2004

2004 IEEE 59th Vehicular Technology Conference. VTC 2004-Spring (IEEE Cat. No.04CH37514), 2004

IEEE Wireless Communications and Networking Conference, 2006. WCNC 2006., 2006