Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689011
R. Chung, Jeng-Kuang Hwang
This paper investigates an inherent but adverse phenomenon called cyclic intersymbol interference (cyclic ISI) occurred in frequency-domain decision-feedback equalizer (FD-DFE). It is due to the cyclic-prefix insertion and modulo operation of the time-domain feedback filter. To analyze this problem, we first formulate the FD-DFE signal model in a compact and insightful vector-matrix form, which allows an efficient derivation of the MMSE receiver coefficients. Next, the cyclic ISI effect can be viewed in terms of the bit-error-rate profile (BERP) which plots the BER with respect to different starting symbol position within a symbol block. From the BERP, it is shown that those leading data symbols suffer more from the cyclic-ISI effect and lead to a high error floor, and the severity depends on the channel eigenvalue spread. Finally, a simple mitigation scheme using zero postfix (ZP) is presented to eliminate the cyclic ISI effect
{"title":"The Effect of Cyclic Intersymbol Interference of Frequency-Domain Decision-Feedback Equalizer","authors":"R. Chung, Jeng-Kuang Hwang","doi":"10.1109/ICICS.2005.1689011","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689011","url":null,"abstract":"This paper investigates an inherent but adverse phenomenon called cyclic intersymbol interference (cyclic ISI) occurred in frequency-domain decision-feedback equalizer (FD-DFE). It is due to the cyclic-prefix insertion and modulo operation of the time-domain feedback filter. To analyze this problem, we first formulate the FD-DFE signal model in a compact and insightful vector-matrix form, which allows an efficient derivation of the MMSE receiver coefficients. Next, the cyclic ISI effect can be viewed in terms of the bit-error-rate profile (BERP) which plots the BER with respect to different starting symbol position within a symbol block. From the BERP, it is shown that those leading data symbols suffer more from the cyclic-ISI effect and lead to a high error floor, and the severity depends on the channel eigenvalue spread. Finally, a simple mitigation scheme using zero postfix (ZP) is presented to eliminate the cyclic ISI effect","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121597322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689120
M. Osoba, J. Irvine, R. Stewart, D. Crawford, F. Westall
The benefits and implementation issues of the homodyne receiver architecture in mobile handsets is presented, with a review of some current techniques used to mitigate the dc-offset generated due to local-oscillator (LO) leakage self-mixing, and a simplified solution is investigated
{"title":"DC Offset Mitigiation in Homodyne Receiver","authors":"M. Osoba, J. Irvine, R. Stewart, D. Crawford, F. Westall","doi":"10.1109/ICICS.2005.1689120","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689120","url":null,"abstract":"The benefits and implementation issues of the homodyne receiver architecture in mobile handsets is presented, with a review of some current techniques used to mitigate the dc-offset generated due to local-oscillator (LO) leakage self-mixing, and a simplified solution is investigated","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122551179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689084
Li Xin, Jiang Xiao-ning, Ye Cheng-qing
A constant-round authenticated group key exchange for dynamic groups scheme has been proposed by Kim et al., (2004). In this paper, an impersonation attack on this scheme is proposed. It shows that any two malicious users can impersonate an honest user to agree some session keys in a new group if these two malicious users have the previous authentication transcripts of this honest user. So, this constant-round authenticated group key exchange scheme can not provide the authenticity as claimed. A proposal to repair this scheme's flaw is proposed in the end
Kim et al.，(2004)提出了动态组方案的常轮认证组密钥交换。本文提出了一种针对该方案的模拟攻击。它表明，任何两个恶意用户都可以冒充一个诚实用户，在一个新的组中同意一些会话密钥，只要这两个恶意用户拥有这个诚实用户以前的身份验证记录。因此，这种恒轮认证组密钥交换方案不能提供所声称的真实性。最后对该方案的缺陷提出了改进建议
{"title":"Attack on a Constant-round Authenticated Group Key Exchange Scheme","authors":"Li Xin, Jiang Xiao-ning, Ye Cheng-qing","doi":"10.1109/ICICS.2005.1689084","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689084","url":null,"abstract":"A constant-round authenticated group key exchange for dynamic groups scheme has been proposed by Kim et al., (2004). In this paper, an impersonation attack on this scheme is proposed. It shows that any two malicious users can impersonate an honest user to agree some session keys in a new group if these two malicious users have the previous authentication transcripts of this honest user. So, this constant-round authenticated group key exchange scheme can not provide the authenticity as claimed. A proposal to repair this scheme's flaw is proposed in the end","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"356 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123109390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689317
P. Pun, P. Ho
We present in the paper a suboptimal multiple-symbol differential detector (MSDD) for differential PSK (DPSK) in Rayleigh flat fading channel that uses the Fano Algorithm as its decoding engine. In contrast to a conventional Fano decoder that only searches forward in time for the most promising transmitted pattern, our Fano decoder searches also in the reverse direction, thus providing a mechanism for error detection and correction. The resultant detector, termed a Bi-Fano MSDD, is capable of delivering excellent error performance at moderate implementation complexity over a wide range of signal-to-noise ration (SNR) and fading rates. As an example, for DQPSK modulation and a Doppler frequency of 3 percent the symbol rate, our Bi-Fano MSDD attains almost the same bit-error probability (BEP) performance as the sphere decoder (an efficient implementation of the optimal MSDD) and there is no noticeable irreducible error floor. The most interesting thing is that the computational complexity of the Bi-Fano MSDD is a very stable function of the SNR. In contrast, the sphere decoder has a complexity that grows exponentially as the SNR decreases. In conclusion, the Bi-Fano MSDD incorporates the desirable attributes of the sphere decoder and the DF-DD into one single embodiment. This is consistent with the observation that the Fano decoder is essentially an intelligent DF-DD that uses the accumulated path metric and a running threshold to guide its movement along the decoding tree
{"title":"Bit Error Probability and Computational Complexity of Bi-directonal Fano Multiple Symbol Differential Detectors","authors":"P. Pun, P. Ho","doi":"10.1109/ICICS.2005.1689317","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689317","url":null,"abstract":"We present in the paper a suboptimal multiple-symbol differential detector (MSDD) for differential PSK (DPSK) in Rayleigh flat fading channel that uses the Fano Algorithm as its decoding engine. In contrast to a conventional Fano decoder that only searches forward in time for the most promising transmitted pattern, our Fano decoder searches also in the reverse direction, thus providing a mechanism for error detection and correction. The resultant detector, termed a Bi-Fano MSDD, is capable of delivering excellent error performance at moderate implementation complexity over a wide range of signal-to-noise ration (SNR) and fading rates. As an example, for DQPSK modulation and a Doppler frequency of 3 percent the symbol rate, our Bi-Fano MSDD attains almost the same bit-error probability (BEP) performance as the sphere decoder (an efficient implementation of the optimal MSDD) and there is no noticeable irreducible error floor. The most interesting thing is that the computational complexity of the Bi-Fano MSDD is a very stable function of the SNR. In contrast, the sphere decoder has a complexity that grows exponentially as the SNR decreases. In conclusion, the Bi-Fano MSDD incorporates the desirable attributes of the sphere decoder and the DF-DD into one single embodiment. This is consistent with the observation that the Fano decoder is essentially an intelligent DF-DD that uses the accumulated path metric and a running threshold to guide its movement along the decoding tree","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126790482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689302
J. Burred, T. Sikora
Sparsity-based source separation algorithms often rely on a transformation into a sparse domain to improve mixture disjointness and therefore facilitate separation. To this end, the most commonly used time-frequency representation has been the short time Fourier transform (STFT). The purpose of this paper is to study the use of auditory-based representations instead of the STFT. We first evaluate the STFT disjointness properties for the case of speech and music signals, and show that auditory representations based on the equal rectangular bandwidth (ERB) and Bark frequency scales can improve the disjointness of the transformed mixtures
{"title":"On the Use of Auditory Representations for Sparsity-Based Sound Source Separation","authors":"J. Burred, T. Sikora","doi":"10.1109/ICICS.2005.1689302","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689302","url":null,"abstract":"Sparsity-based source separation algorithms often rely on a transformation into a sparse domain to improve mixture disjointness and therefore facilitate separation. To this end, the most commonly used time-frequency representation has been the short time Fourier transform (STFT). The purpose of this paper is to study the use of auditory-based representations instead of the STFT. We first evaluate the STFT disjointness properties for the case of speech and music signals, and show that auditory representations based on the equal rectangular bandwidth (ERB) and Bark frequency scales can improve the disjointness of the transformed mixtures","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114164960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689180
Jiong Zhou, Gang Li
A new adaptive algorithm for direct frequency estimation is developed using a constrained IIR notch filter. The basic characteristics of this proposed algorithm are that the computational cost is very low and that the stability of the adaptive IIR notch filter can be guaranteed by a normal state-space realization. These features make the proposed adaptive algorithm both efficient and robust
{"title":"An Efficient Adaptive Direct Frequency Estimation Algorithm Using A Constrained IR Notch Filter with Guaranteed Stability","authors":"Jiong Zhou, Gang Li","doi":"10.1109/ICICS.2005.1689180","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689180","url":null,"abstract":"A new adaptive algorithm for direct frequency estimation is developed using a constrained IIR notch filter. The basic characteristics of this proposed algorithm are that the computational cost is very low and that the stability of the adaptive IIR notch filter can be guaranteed by a normal state-space realization. These features make the proposed adaptive algorithm both efficient and robust","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121110940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689049
Thanatat Wattanasuwakull, W. Benjapolakul
This paper tends to reduce the peak-to-aver age power ratio (PAPR) of the orthogonal frequency division multiplexing (OFDM) signal by using a method of tone reservation and tone injection. To reduce the peak of the OFDM signal, the proposed method is based on the reservation of some tones that are not used to carry data symbols. The proposed method replaces the appropriate chosen tones that carry data symbols with the dummy symbols. Data symbols, which are carried by replaced tones, are carried by reserved tones. The magnitude of the signal constellation of the dummy symbols must be larger than that of the original OFDM symbol so that the positions of the replaced tones can be easily detected by the receiver. There is no need to send any side information. The proposed method with proposed iterative search algorithm is an efficient scheme to reduce the PAPR of the OFDM signal with low complexity. However, it retards data rate and increases a little average power of the transmitter due to the dummy symbols that replace some tones and the usage of larger signal constellation
{"title":"PAPR Reduction for OFDM Transmission by using a method of Tone Reservation and Tone Injection","authors":"Thanatat Wattanasuwakull, W. Benjapolakul","doi":"10.1109/ICICS.2005.1689049","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689049","url":null,"abstract":"This paper tends to reduce the peak-to-aver age power ratio (PAPR) of the orthogonal frequency division multiplexing (OFDM) signal by using a method of tone reservation and tone injection. To reduce the peak of the OFDM signal, the proposed method is based on the reservation of some tones that are not used to carry data symbols. The proposed method replaces the appropriate chosen tones that carry data symbols with the dummy symbols. Data symbols, which are carried by replaced tones, are carried by reserved tones. The magnitude of the signal constellation of the dummy symbols must be larger than that of the original OFDM symbol so that the positions of the replaced tones can be easily detected by the receiver. There is no need to send any side information. The proposed method with proposed iterative search algorithm is an efficient scheme to reduce the PAPR of the OFDM signal with low complexity. However, it retards data rate and increases a little average power of the transmitter due to the dummy symbols that replace some tones and the usage of larger signal constellation","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"68 50","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113937659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689007
J. Allen
We introduce two new perfect reconstruction (P.R.) decompositions for signals on a hexagon lattice. One is an orthogonal compaction (coding) transform similar to that used in the Simoncelli-Adelson quadtree pyramid, but with perfect reconstruction and compact integer-valued filters. The other is a 3-ary "blurring" filter bank which has a perfect inverse ("sharpening") filter bank. Each example filter bank has better properties than other banks proposed for the hexagon grid, and, it would seem, better properties than any possible comparable filter bank for the square grid
{"title":"Perfect Reconstruction Filter Banks for the Hexagon Grid","authors":"J. Allen","doi":"10.1109/ICICS.2005.1689007","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689007","url":null,"abstract":"We introduce two new perfect reconstruction (P.R.) decompositions for signals on a hexagon lattice. One is an orthogonal compaction (coding) transform similar to that used in the Simoncelli-Adelson quadtree pyramid, but with perfect reconstruction and compact integer-valued filters. The other is a 3-ary \"blurring\" filter bank which has a perfect inverse (\"sharpening\") filter bank. Each example filter bank has better properties than other banks proposed for the hexagon grid, and, it would seem, better properties than any possible comparable filter bank for the square grid","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131270294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689178
P. Mahapatra, Vishnu Vardhan Makkapati
Studies are carried out on a contour-based method for highly compressing voluminous weather radar reflectivity data to optimize the compression and reconstruction parameters. In particular, the effects of the choice of thresholds and the degree of smoothing at encoding and retrieval ends are studied with respect to achievable compression ratios, root-mean-square error of the retrieved contours, and the visual fidelity of the reconstructed reflectivity images. Results are presented for multiple actual Doppler weather radar reflectivity data sets
{"title":"Studies on a High-Compression Technique for Weather Radar Reflectivity Data","authors":"P. Mahapatra, Vishnu Vardhan Makkapati","doi":"10.1109/ICICS.2005.1689178","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689178","url":null,"abstract":"Studies are carried out on a contour-based method for highly compressing voluminous weather radar reflectivity data to optimize the compression and reconstruction parameters. In particular, the effects of the choice of thresholds and the degree of smoothing at encoding and retrieval ends are studied with respect to achievable compression ratios, root-mean-square error of the retrieved contours, and the visual fidelity of the reconstructed reflectivity images. Results are presented for multiple actual Doppler weather radar reflectivity data sets","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116529992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2005-12-06DOI: 10.1109/ICICS.2005.1689169
Z.G. Li, S. Xie, Cheng Chen, Y. Soh, C. Wen
A charging scheme and a flow control scheme are designed for a fully cooperative network by using a new concept of generalized Nash equilibrium that is based on an assumption that each player is wise and intends to minimize instead of maximize his/her expected utility payoff (or maximize the opponent's utility payoff). In our scheme, each link will increase its price when the system is under-loaded, and decrease its price when the system is over-loaded. On the other hand, the sending rate of each source is a monotonous non-decreasing function of the price, i.e., each source will increase transmission rate when the price does not fall and decrease transmission rate when the price falls. Clearly, our scheme is different from existing network framework that is based on the conventional microeconomic system. With our scheme, the network is harmonious in the sense that besides all sources cooperate with each other, sources and links are also cooperative with each other. This distinguishes our scheme from existing cooperative scheme in the sense that in the existing schemes, only sources are cooperative with each other. With our scheme, each link has an incentive to increase its capacity because it can get more profit. This is very helpful for the evolution of the Internet
{"title":"A Fully Cooperative Network","authors":"Z.G. Li, S. Xie, Cheng Chen, Y. Soh, C. Wen","doi":"10.1109/ICICS.2005.1689169","DOIUrl":"https://doi.org/10.1109/ICICS.2005.1689169","url":null,"abstract":"A charging scheme and a flow control scheme are designed for a fully cooperative network by using a new concept of generalized Nash equilibrium that is based on an assumption that each player is wise and intends to minimize instead of maximize his/her expected utility payoff (or maximize the opponent's utility payoff). In our scheme, each link will increase its price when the system is under-loaded, and decrease its price when the system is over-loaded. On the other hand, the sending rate of each source is a monotonous non-decreasing function of the price, i.e., each source will increase transmission rate when the price does not fall and decrease transmission rate when the price falls. Clearly, our scheme is different from existing network framework that is based on the conventional microeconomic system. With our scheme, the network is harmonious in the sense that besides all sources cooperate with each other, sources and links are also cooperative with each other. This distinguishes our scheme from existing cooperative scheme in the sense that in the existing schemes, only sources are cooperative with each other. With our scheme, each link has an incentive to increase its capacity because it can get more profit. This is very helpful for the evolution of the Internet","PeriodicalId":425178,"journal":{"name":"2005 5th International Conference on Information Communications & Signal Processing","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121854593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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