Pub Date : 2010-04-21DOI: 10.1109/WTS.2010.5479640
T. Ketseoglou
A realistic framework for cooperation diversity is presented for Orthogonal Frequency Division Multiplexing (OFDM) systems with clipping type of transmitter non-linearities. The destination node processes together the received information from the source node and a single, selection algorithm dependent relay one (if any of the candidate relays succeeds in decoding the original OFDM packet sent). The relayed packets are the same with the direct ones (repetition coding), so that simpler receiver processing applies. The destination node employs an optimized, iterative receiver structure based on Turbo processing, in which both the channels and the clipping distortion are (iteratively) estimated. The relaying nodes receive the source-node emanating packets in a standard, non-iterative fashion, due to delay constraints. Two methods of relay node selection are considered: a) Random Relay Selection (RRS), and b) Optimal Relay Selection (ORS). High gains are showed for the proposed approach, due to the synergy between clipping distortion, channel estimation and multiple transmission paths, based on node cooperation diversity. In addition, when the number of candidate relay nodes increases, it is shown that ORS performs significantly better than RRS.
{"title":"Cooperation diversity scenarios for clipped OFDM with iterative destination node reception","authors":"T. Ketseoglou","doi":"10.1109/WTS.2010.5479640","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479640","url":null,"abstract":"A realistic framework for cooperation diversity is presented for Orthogonal Frequency Division Multiplexing (OFDM) systems with clipping type of transmitter non-linearities. The destination node processes together the received information from the source node and a single, selection algorithm dependent relay one (if any of the candidate relays succeeds in decoding the original OFDM packet sent). The relayed packets are the same with the direct ones (repetition coding), so that simpler receiver processing applies. The destination node employs an optimized, iterative receiver structure based on Turbo processing, in which both the channels and the clipping distortion are (iteratively) estimated. The relaying nodes receive the source-node emanating packets in a standard, non-iterative fashion, due to delay constraints. Two methods of relay node selection are considered: a) Random Relay Selection (RRS), and b) Optimal Relay Selection (ORS). High gains are showed for the proposed approach, due to the synergy between clipping distortion, channel estimation and multiple transmission paths, based on node cooperation diversity. In addition, when the number of candidate relay nodes increases, it is shown that ORS performs significantly better than RRS.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127796526","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479674
André Ferreira, P. Carvalho, S. R. Lima
In NGN service-provisioning platforms the existence of an efficient and flexible admission control mechanism is essential for providing quality of service in a reliable and stable way, avoiding congestion scenarios caused by indiscriminate and uncontrolled service requests. The capability of modulating and regulating the rate of call acceptance, and provide service differentiation allow indirect control of the load submitted to the platform. This paper presents a service admission control solution that enables to differentiate, limit and modulate the rate by which service requests are submitted into a NGN service-provisioning platform. The solution is focused on providing a fair level of bandwidth sharing among service classes, in a configurable and dynamic way so that it can adapt the distribution by which service requests are served. To sustain the design goals of our solution, major scheduling disciplines and rate control mechanisms are here studied and compared in order to elect the more adequate components. The implemented solution was submitted to unit and charge tests; the results show its effectiveness and robustness in controlling and differentiating incoming service calls.
{"title":"Adaptive admission control in a NGN service platform","authors":"André Ferreira, P. Carvalho, S. R. Lima","doi":"10.1109/WTS.2010.5479674","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479674","url":null,"abstract":"In NGN service-provisioning platforms the existence of an efficient and flexible admission control mechanism is essential for providing quality of service in a reliable and stable way, avoiding congestion scenarios caused by indiscriminate and uncontrolled service requests. The capability of modulating and regulating the rate of call acceptance, and provide service differentiation allow indirect control of the load submitted to the platform. This paper presents a service admission control solution that enables to differentiate, limit and modulate the rate by which service requests are submitted into a NGN service-provisioning platform. The solution is focused on providing a fair level of bandwidth sharing among service classes, in a configurable and dynamic way so that it can adapt the distribution by which service requests are served. To sustain the design goals of our solution, major scheduling disciplines and rate control mechanisms are here studied and compared in order to elect the more adequate components. The implemented solution was submitted to unit and charge tests; the results show its effectiveness and robustness in controlling and differentiating incoming service calls.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130890384","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479668
Daniela Radakovic, R. Ansari, Yingwei Yao
A novel COntent-Based Rate-Adaptation (COBRA) model is proposed to improve the quality of video transmission over multiple-input multiple-output (MIMO) system with channel state information feedback (CSI). The model captures relationships among the video content type, video sub-stream bit-rates, achievable peak signal-to-noise ratios (PSNR), and channel bit error rate (BER). COBRA facilitates joint selection of physical layer parameters and video sub-stream configuration. Unlike existing methods, the COBRA model offers an efficient way of balancing losses in PSNR due to channel errors and non-transmission of some enhancements layers in a sub-stream, with a judicious mechanism of selecting sub-stream configurations and communication parameters. Simulations show that COBRA maintains video quality at acceptable levels over wide range of low channel signal-to-noise ratio (SNR) values. It achieves the same video PSNR as obtained by the complete stream transmission at 10 dB higher channel SNR.
{"title":"Content-Based Rate-Adaptive transfer of SVC-encoded video over MIMO communication systems","authors":"Daniela Radakovic, R. Ansari, Yingwei Yao","doi":"10.1109/WTS.2010.5479668","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479668","url":null,"abstract":"A novel COntent-Based Rate-Adaptation (COBRA) model is proposed to improve the quality of video transmission over multiple-input multiple-output (MIMO) system with channel state information feedback (CSI). The model captures relationships among the video content type, video sub-stream bit-rates, achievable peak signal-to-noise ratios (PSNR), and channel bit error rate (BER). COBRA facilitates joint selection of physical layer parameters and video sub-stream configuration. Unlike existing methods, the COBRA model offers an efficient way of balancing losses in PSNR due to channel errors and non-transmission of some enhancements layers in a sub-stream, with a judicious mechanism of selecting sub-stream configurations and communication parameters. Simulations show that COBRA maintains video quality at acceptable levels over wide range of low channel signal-to-noise ratio (SNR) values. It achieves the same video PSNR as obtained by the complete stream transmission at 10 dB higher channel SNR.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130335323","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479643
Ramdane Chouitem
A conventional OFDM system often poses a stringent linearity requirement to the transmitter, especially the radio-frequency power amplifier (RFPA), to maintain its bit error rate (BER). As a result, the output power from a RFPA is often limited, thus, the communication distance is compromised. With the deployment of WiMAX (IEEE 802.16), which is targeting at the mobile market, the communication distance is a concern. In this project, we propose to use Adaptive Modulation and Coding (AMC) to adaptively control the digital modulation and the output power of a RFPA. When the AMC selects the modulation order with the coding rate to achieve the targeted BER, the output power of a RFPA can be increased as long as its Error Vector Magnitude (EVM) is less than the required. Therefore, the communication distance of an OFDM system could be intelligently extended.
{"title":"EVM based AMC for an OFDM system","authors":"Ramdane Chouitem","doi":"10.1109/WTS.2010.5479643","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479643","url":null,"abstract":"A conventional OFDM system often poses a stringent linearity requirement to the transmitter, especially the radio-frequency power amplifier (RFPA), to maintain its bit error rate (BER). As a result, the output power from a RFPA is often limited, thus, the communication distance is compromised. With the deployment of WiMAX (IEEE 802.16), which is targeting at the mobile market, the communication distance is a concern. In this project, we propose to use Adaptive Modulation and Coding (AMC) to adaptively control the digital modulation and the output power of a RFPA. When the AMC selects the modulation order with the coding rate to achieve the targeted BER, the output power of a RFPA can be increased as long as its Error Vector Magnitude (EVM) is less than the required. Therefore, the communication distance of an OFDM system could be intelligently extended.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131043429","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479653
Jaewook Shim, K. Yun, R. Cruz
We present a wireless switching architecture that allows a self-interference-free asynchronous packet communication in multi-channel wireless switching networks. We propose a system architecture to get around the self-interference problem, which arises due to the proximity among RF devices in the switch and the large difference in strengths between receiving and transmitting signals. We then present a straightforward solution of separating the frequency spectra used for receiving and transmitting signals and propose a MAC/PHY cross-layer protocol for efficiently managing the channel bandwidth for asynchronous packet-based communication. We show that, when a K-port wireless switch with each port providing 20MHz of bidirectional bandwidth, the total communication bandwidth can be increased to 1.4K×20MHz, which is about 2K times as high as a wireless access point with 20MHz per channel. Finally, we introduce a scheduling scheme with a dynamic load balancing to ensure global fairness for all users. The performance of our algorithm is compared to that of the Least-Loaded-First (LLF) user assignment policy using simulations.
{"title":"An efficient wireless switching architecture","authors":"Jaewook Shim, K. Yun, R. Cruz","doi":"10.1109/WTS.2010.5479653","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479653","url":null,"abstract":"We present a wireless switching architecture that allows a self-interference-free asynchronous packet communication in multi-channel wireless switching networks. We propose a system architecture to get around the self-interference problem, which arises due to the proximity among RF devices in the switch and the large difference in strengths between receiving and transmitting signals. We then present a straightforward solution of separating the frequency spectra used for receiving and transmitting signals and propose a MAC/PHY cross-layer protocol for efficiently managing the channel bandwidth for asynchronous packet-based communication. We show that, when a K-port wireless switch with each port providing 20MHz of bidirectional bandwidth, the total communication bandwidth can be increased to 1.4K×20MHz, which is about 2K times as high as a wireless access point with 20MHz per channel. Finally, we introduce a scheduling scheme with a dynamic load balancing to ensure global fairness for all users. The performance of our algorithm is compared to that of the Least-Loaded-First (LLF) user assignment policy using simulations.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127100050","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479659
I. Butun, A. Talay, D. Altilar, M. Khalid, R. Sankar
Wireless technology has enabled the development of increasingly diverse applications and devices resulting in an exponential growth in usage and services. These advancements made the radio frequency spectrum a scarce resource, and consequently, its efficient use is of the ultimate importance. To cope with the growing demand, network design focused on increasing the spectral efficiency by making use of advancement in Cognitive Radio technology. Cognitive Radio can reduce the spectrum shortage problem by enabling unlicensed users equipped with Cognitive Radios to reuse and share the licensed spectrum bands. Using the fact that a Cognitive Radio is capable of sensing the environmental conditions and automatically adapting its operating parameters in order to enhance network performance, we would like to make use of its knowledge to predict the mobility of Cognitive Radio users to improve the overall performance of the Cognitive Radio network. This study makes novel use of mobility prediction techniques to enhance reliability, bandwidth efficiency and scalability of the cognitive radio networks. Firstly, prediction techniques are evaluated and compared for prediction accuracy. Secondly, routing protocol reliability, efficiency and scalability performances are evaluated under different prediction techniques. Simulation results verify the performance improvements even with moderate accuracy predictors. Results clearly show that hybrid Markov CDF prediction performs the best. When compared with no prediction it significantly improves average reliability and efficiency by 11% and 8%, respectively.
{"title":"Impact of mobility prediction on the performance of Cognitive Radio networks","authors":"I. Butun, A. Talay, D. Altilar, M. Khalid, R. Sankar","doi":"10.1109/WTS.2010.5479659","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479659","url":null,"abstract":"Wireless technology has enabled the development of increasingly diverse applications and devices resulting in an exponential growth in usage and services. These advancements made the radio frequency spectrum a scarce resource, and consequently, its efficient use is of the ultimate importance. To cope with the growing demand, network design focused on increasing the spectral efficiency by making use of advancement in Cognitive Radio technology. Cognitive Radio can reduce the spectrum shortage problem by enabling unlicensed users equipped with Cognitive Radios to reuse and share the licensed spectrum bands. Using the fact that a Cognitive Radio is capable of sensing the environmental conditions and automatically adapting its operating parameters in order to enhance network performance, we would like to make use of its knowledge to predict the mobility of Cognitive Radio users to improve the overall performance of the Cognitive Radio network. This study makes novel use of mobility prediction techniques to enhance reliability, bandwidth efficiency and scalability of the cognitive radio networks. Firstly, prediction techniques are evaluated and compared for prediction accuracy. Secondly, routing protocol reliability, efficiency and scalability performances are evaluated under different prediction techniques. Simulation results verify the performance improvements even with moderate accuracy predictors. Results clearly show that hybrid Markov CDF prediction performs the best. When compared with no prediction it significantly improves average reliability and efficiency by 11% and 8%, respectively.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122116215","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479633
Yoon Seok Yang, G. Choi
This paper presents a low-power baseband-video joint decoder design using a novel unequal error protection (UEP) scheme for wireless telecommunications. This method is developed for H.264 layered (data partitioned) video transmission over low density parity check (LDPC) codec. We exploit the fact that not all transmitted data require the same level of error protection; this is known as unequal error protection. In particular, we use a variable iteration LDPC decoding scheme along with H.264 data partitioning (DP). In this scheme, we determine and use variable iterations that are needed by the LDPC baseband decoder to achieve pre-specified image qualities at the receiver and apply power gating to minimize energy consumption.
{"title":"Low-power baseband processing for wireless multimedia systems using unequal error protection","authors":"Yoon Seok Yang, G. Choi","doi":"10.1109/WTS.2010.5479633","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479633","url":null,"abstract":"This paper presents a low-power baseband-video joint decoder design using a novel unequal error protection (UEP) scheme for wireless telecommunications. This method is developed for H.264 layered (data partitioned) video transmission over low density parity check (LDPC) codec. We exploit the fact that not all transmitted data require the same level of error protection; this is known as unequal error protection. In particular, we use a variable iteration LDPC decoding scheme along with H.264 data partitioning (DP). In this scheme, we determine and use variable iterations that are needed by the LDPC baseband decoder to achieve pre-specified image qualities at the receiver and apply power gating to minimize energy consumption.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117213292","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479671
Shikha Tripathi, R. Mathur, J. Arya
One key objective of Software Defined radio is to implement multiple standards on common hardware. This can be achieved by partial reconfiguration of Field Programmable Gate Array (FPGA) in which some part of the FPGA remains active while other gets reconfigured. This paper proposes partially reconfigurable design of unified turbo encoder of two 3G standards-3GPP and 3GPP2 on FPGA Xilinx Virtex- IV. The design shows substantial improvement in hardware implementation of the interleavers over the previous designs. In order to achieve the best possible results with partial reconfiguration, maximum common functionality from both the turbo encoders has been identified and a unified architecture has been proposed. Novel ways have been devised to perform the computationally intensive operations of the 3GPP interleaver with minimal hardware requirement and least possible number of clock cycles.
软件定义无线电的一个关键目标是在通用硬件上实现多种标准。这可以通过部分重新配置现场可编程门阵列(FPGA)来实现，其中FPGA的某些部分保持活跃，而其他部分被重新配置。本文提出了在Xilinx Virtex- IV FPGA上实现3gpp和3GPP2两种3G标准统一turbo编码器的部分可重构设计。该设计在交织器的硬件实现上比以往的设计有了很大的改进。为了实现部分重构的最佳结果，已经确定了两个涡轮编码器的最大共同功能，并提出了一个统一的架构。已经设计了新的方法来执行3GPP交织器的计算密集型操作，具有最小的硬件要求和尽可能少的时钟周期。
{"title":"Unified 3GPP and 3GPP2 turbo encoder FPGA implementation using run-time partial reconfiguration","authors":"Shikha Tripathi, R. Mathur, J. Arya","doi":"10.1109/WTS.2010.5479671","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479671","url":null,"abstract":"One key objective of Software Defined radio is to implement multiple standards on common hardware. This can be achieved by partial reconfiguration of Field Programmable Gate Array (FPGA) in which some part of the FPGA remains active while other gets reconfigured. This paper proposes partially reconfigurable design of unified turbo encoder of two 3G standards-3GPP and 3GPP2 on FPGA Xilinx Virtex- IV. The design shows substantial improvement in hardware implementation of the interleavers over the previous designs. In order to achieve the best possible results with partial reconfiguration, maximum common functionality from both the turbo encoders has been identified and a unified architecture has been proposed. Novel ways have been devised to perform the computationally intensive operations of the 3GPP interleaver with minimal hardware requirement and least possible number of clock cycles.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129308809","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479634
Yanyan Wu
High peak-to-average power ratio (PAPR) in multi-carrier systems such as OFDM can significantly reduce power efficiency and performance. Existing methods to mitigate this problem are known in three major categories, i.e. clipping /filtering, convex optimisation and stochastic approach. In this paper, a polynomial phasing scheme is proposed to achieve maximum PAPR reduction for a multicarrier OFDM signal. Using this scheme, each subcarrier phase is adjusted by a polynomial function of the subcarrier index. The coefficients of such polynomial function can be determined at the transmitter by a search method, and can be conveyed using existing pilot tones. The scheme promising maximum PAPR reduction with no distortion to the spectral mask or loss in data rate requires little change to existing OFDM standards.
{"title":"A polynomial phasing scheme to realize minimum crest factor for multicarrier transmission","authors":"Yanyan Wu","doi":"10.1109/WTS.2010.5479634","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479634","url":null,"abstract":"High peak-to-average power ratio (PAPR) in multi-carrier systems such as OFDM can significantly reduce power efficiency and performance. Existing methods to mitigate this problem are known in three major categories, i.e. clipping /filtering, convex optimisation and stochastic approach. In this paper, a polynomial phasing scheme is proposed to achieve maximum PAPR reduction for a multicarrier OFDM signal. Using this scheme, each subcarrier phase is adjusted by a polynomial function of the subcarrier index. The coefficients of such polynomial function can be determined at the transmitter by a search method, and can be conveyed using existing pilot tones. The scheme promising maximum PAPR reduction with no distortion to the spectral mask or loss in data rate requires little change to existing OFDM standards.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132276018","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 : 2010-04-21DOI: 10.1109/WTS.2010.5479648
M. Hoseinzade, K. Mohamed-Pour, S. Andargoli, A. Gharanjik
In this paper, we propose a new channel estimation algorithm for orthogonal frequency division multiplexing (OFDM) systems. For fast fading environment, we introduce a new method which is extended to the Alamouti Coded OFDM case. At the first stage of this algorithm, the channel response is estimated for pilot sub-carriers and then, the channel response for data sub-carriers are interpolated by Gaussian Radial Basis function as it is an efficient nonlinear interpolator. The post-processing and filtering on the estimated channel taps energy are proposed to improve the estimation performance and reduce the noise effects of primary estimation, which is caused by LS estimation at pilot data. The accuracy of our channel estimation algorithm is improved by using iterative decision feedback. The decision feedback method is used to update channel parameters in each OFDM symbol. The effectiveness of new techniques is demonstrated through the simulation of an Alamouti coded OFDM system with two-transmit and two-receive antennas. Finally, the results are analyzed and compared with previous algorithms which show performance enhancement.
{"title":"Decision feedback channel estimation for Alamouti coded OFDM-MIMO systems","authors":"M. Hoseinzade, K. Mohamed-Pour, S. Andargoli, A. Gharanjik","doi":"10.1109/WTS.2010.5479648","DOIUrl":"https://doi.org/10.1109/WTS.2010.5479648","url":null,"abstract":"In this paper, we propose a new channel estimation algorithm for orthogonal frequency division multiplexing (OFDM) systems. For fast fading environment, we introduce a new method which is extended to the Alamouti Coded OFDM case. At the first stage of this algorithm, the channel response is estimated for pilot sub-carriers and then, the channel response for data sub-carriers are interpolated by Gaussian Radial Basis function as it is an efficient nonlinear interpolator. The post-processing and filtering on the estimated channel taps energy are proposed to improve the estimation performance and reduce the noise effects of primary estimation, which is caused by LS estimation at pilot data. The accuracy of our channel estimation algorithm is improved by using iterative decision feedback. The decision feedback method is used to update channel parameters in each OFDM symbol. The effectiveness of new techniques is demonstrated through the simulation of an Alamouti coded OFDM system with two-transmit and two-receive antennas. Finally, the results are analyzed and compared with previous algorithms which show performance enhancement.","PeriodicalId":117027,"journal":{"name":"2010 Wireless Telecommunications Symposium (WTS)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115910494","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}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：