Pub Date : 2000-05-15DOI: 10.1109/VETECS.2000.851624
D. Didascalou, J. Maurer, W. Wiesbeck
A measurement campaign has been carried out in the Berlin subway to characterize EM-wave propagation in underground railroad tunnels. The received power levels at 945 MHz, and 1853.4 MHz are used to evaluate the attenuation and the fading characteristics in a curved, arched-shaped tunnel. The measurements are compared to ray-optical modelling results. It is shown that the geometry of a tunnel, especially the cross-sectional shape and the course, is of major impact on the propagation behaviour and thus on the accuracy of the modelling.
{"title":"Natural wave propagation in subway tunnels at mobile communications frequencies","authors":"D. Didascalou, J. Maurer, W. Wiesbeck","doi":"10.1109/VETECS.2000.851624","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851624","url":null,"abstract":"A measurement campaign has been carried out in the Berlin subway to characterize EM-wave propagation in underground railroad tunnels. The received power levels at 945 MHz, and 1853.4 MHz are used to evaluate the attenuation and the fading characteristics in a curved, arched-shaped tunnel. The measurements are compared to ray-optical modelling results. It is shown that the geometry of a tunnel, especially the cross-sectional shape and the course, is of major impact on the propagation behaviour and thus on the accuracy of the modelling.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115088943","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851657
S. Roy, D. Falconer
This paper investigates space-time receiver architectures in multi-user wireless systems where optimal idealized (infinite-length) space-time filtering is applied to minimize the mean-square error. Both feedforward, decision-feedback and cross-decision feedback filters are employed; it follows that not only does the system eliminate the post-cursor ISI (intersymbol interference) but also some portion of the post-cursor CCI (co-channel interference). Such a receiver is most useful in the context of an SDMA (space division multiple access) system since the base station then has readily available knowledge on the decisions of the in-cell co-channel interfering signals. However, significant CCI is also received from outside the cell for which there is normally no decision information available. Therefore, in-cell and out-of-cell co-channel interferers will be treated differently by the receiver since no cross-feedback filter can be implemented for the out-of-cell signals. Our analysis leads to a closed-form expression for the minimum achievable MSE (mean-square error) for both fully- and partially-connected cross-decision feedback systems (XDF). Numerical results compare the performance of XDF systems with standard space-time DF and linear processing as well as the matched-filter bound.
{"title":"Multi-user decision-feedback space-time processing with partial cross-feedback connectivity","authors":"S. Roy, D. Falconer","doi":"10.1109/VETECS.2000.851657","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851657","url":null,"abstract":"This paper investigates space-time receiver architectures in multi-user wireless systems where optimal idealized (infinite-length) space-time filtering is applied to minimize the mean-square error. Both feedforward, decision-feedback and cross-decision feedback filters are employed; it follows that not only does the system eliminate the post-cursor ISI (intersymbol interference) but also some portion of the post-cursor CCI (co-channel interference). Such a receiver is most useful in the context of an SDMA (space division multiple access) system since the base station then has readily available knowledge on the decisions of the in-cell co-channel interfering signals. However, significant CCI is also received from outside the cell for which there is normally no decision information available. Therefore, in-cell and out-of-cell co-channel interferers will be treated differently by the receiver since no cross-feedback filter can be implemented for the out-of-cell signals. Our analysis leads to a closed-form expression for the minimum achievable MSE (mean-square error) for both fully- and partially-connected cross-decision feedback systems (XDF). Numerical results compare the performance of XDF systems with standard space-time DF and linear processing as well as the matched-filter bound.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122032496","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851414
F. Khan, S. Kumar, K. Medepalli, S. Nanda
This paper provides performance results for TCP over cdma2000 radio link protocol (RLP). The simulations are performed for a single user running a long FTP application with "infinite" data backlog. With the assumption of a long FTP application, maximum TCP throughput is the relevant optimization metric. The goal is to analyze the impact of TCP window size, RTT, wireless channel bandwidth, FER model and RLP transmission delays on end-to-end transport. The IS-95 and its evolutions (i.e. IS-95B and cdma2000) use a NAK-based RLP. The number of rounds of NAKs and the number of retransmissions in each round is varied. We analyze the impact of varying different RLP parameters and retransmission schemes on TCP throughput. Our findings demonstrate that the (1,1,1,1,1) NAK scheme outperforms the (2,3) NAK scheme when the errors are correlated. This is also true for non-correlated error case and larger TCP window size. However, with non-correlated errors and comparatively smaller TCP window size, the (2,3) NAK scheme performs better. It was also observed that the TCP throughput is not severely penalized up to link error rates of 10% (approximately 15% loss in TCP throughput at 10% FER).
{"title":"TCP performance over cdma2000 RLP","authors":"F. Khan, S. Kumar, K. Medepalli, S. Nanda","doi":"10.1109/VETECS.2000.851414","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851414","url":null,"abstract":"This paper provides performance results for TCP over cdma2000 radio link protocol (RLP). The simulations are performed for a single user running a long FTP application with \"infinite\" data backlog. With the assumption of a long FTP application, maximum TCP throughput is the relevant optimization metric. The goal is to analyze the impact of TCP window size, RTT, wireless channel bandwidth, FER model and RLP transmission delays on end-to-end transport. The IS-95 and its evolutions (i.e. IS-95B and cdma2000) use a NAK-based RLP. The number of rounds of NAKs and the number of retransmissions in each round is varied. We analyze the impact of varying different RLP parameters and retransmission schemes on TCP throughput. Our findings demonstrate that the (1,1,1,1,1) NAK scheme outperforms the (2,3) NAK scheme when the errors are correlated. This is also true for non-correlated error case and larger TCP window size. However, with non-correlated errors and comparatively smaller TCP window size, the (2,3) NAK scheme performs better. It was also observed that the TCP throughput is not severely penalized up to link error rates of 10% (approximately 15% loss in TCP throughput at 10% FER).","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116811882","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851396
Y. C. Kim, B. Choi
We present a method of suppressing mutual interference among pulse-type radars of an identical type. We separate the true self-reflection from the synchronous false reflection by controlling the pulse emission of a radar in an orthogonal on-off pattern. The interference signal is identified by observing the received signal in off-intervals. The identified interference signal can be easily removed from the received signal in the on-intervals. P/sub PA/ and P/sub M/ are derived with the I-Q demodulation scheme, where Gaussian noise alone is Rayleigh-distributed and reflected radar pulses with Gaussian noise are Rician-distributed. The threshold of detection is adaptively adjusted to prevent the increase of P/sub M/. We also present an algorithm for tracking the good region. In the experimental result, P/sub FA/ decreases by an order of 10/sup 4/ within the good region of threshold values, when compared with the conventional M of N method.
提出了一种抑制同类型脉冲型雷达相互干扰的方法。通过控制雷达脉冲发射的正交开关模式，分离了雷达的真自反射和同步假反射。干扰信号是通过观察非间隔接收信号来识别的。识别出的干扰信号可以很容易地在导通间隔内从接收信号中去除。P/sub PA/和P/sub M/采用I-Q解调方案推导，其中高斯噪声单独为瑞利分布，高斯噪声反射雷达脉冲为瑞利分布。自适应调整检测阈值，防止P/sub M/的增加。我们还提出了一种跟踪良好区域的算法。实验结果表明，与传统的M of N方法相比，P/sub FA/在良好的阈值区域内降低了10/sup 4/个数量级。
{"title":"Vehicular pulse-radar with very low false alarm rate by on-off pulse control and adaptive threshold","authors":"Y. C. Kim, B. Choi","doi":"10.1109/VETECS.2000.851396","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851396","url":null,"abstract":"We present a method of suppressing mutual interference among pulse-type radars of an identical type. We separate the true self-reflection from the synchronous false reflection by controlling the pulse emission of a radar in an orthogonal on-off pattern. The interference signal is identified by observing the received signal in off-intervals. The identified interference signal can be easily removed from the received signal in the on-intervals. P/sub PA/ and P/sub M/ are derived with the I-Q demodulation scheme, where Gaussian noise alone is Rayleigh-distributed and reflected radar pulses with Gaussian noise are Rician-distributed. The threshold of detection is adaptively adjusted to prevent the increase of P/sub M/. We also present an algorithm for tracking the good region. In the experimental result, P/sub FA/ decreases by an order of 10/sup 4/ within the good region of threshold values, when compared with the conventional M of N method.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"75 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125956672","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851276
J. Laiho-Steffens, A. Wacker, P. Aikio
The 3/sup rd/ generation cellular systems will offer services with higher bit rates compared to today's networks and therefore for an operator it is of utmost importance to exploit all possible resources to improve the capacity and quality of service of the radio network. The scope of this paper is to demonstrate with simulations how careful radio network planning can improve the network capacity and quality of service (QoS). Furthermore, it is demonstrated how the site configuration expansions can support the network capacity growth. Example results of omni-, three-, four- and six sectored site configuration simulations are presented including four different antennas and various different tilts. Furthermore a test case is shown to demonstrate the effect of a mast head amplifier (MHA) in the WCDMA uplink.
{"title":"The impact of the radio network planning and site configuration on the WCDMA network capacity and quality of service","authors":"J. Laiho-Steffens, A. Wacker, P. Aikio","doi":"10.1109/VETECS.2000.851276","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851276","url":null,"abstract":"The 3/sup rd/ generation cellular systems will offer services with higher bit rates compared to today's networks and therefore for an operator it is of utmost importance to exploit all possible resources to improve the capacity and quality of service of the radio network. The scope of this paper is to demonstrate with simulations how careful radio network planning can improve the network capacity and quality of service (QoS). Furthermore, it is demonstrated how the site configuration expansions can support the network capacity growth. Example results of omni-, three-, four- and six sectored site configuration simulations are presented including four different antennas and various different tilts. Furthermore a test case is shown to demonstrate the effect of a mast head amplifier (MHA) in the WCDMA uplink.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126124706","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851656
W.C.-Y. Lee, D.J.Y. Lee
An accurate microcell prediction model needs to consider the effects of terrain contour and building factors on urban microcell radio propagation. An inexpensive and accurate way of executing this prediction is to utilize readily accessible street and terrain data as proposed in this paper. Various comparisons were done within the San Francisco Bay Area proving that the model calculations for the combination of attenuation from building and gain or loss from terrain (diffraction loss and effective antenna gains) encountered in the path of the mobile are fairly accurate. The street data utilized can be employed as either the base for creating the building database, or as a method of fine-tuning to improve the accuracy of the microcell model.
{"title":"Microcell prediction by street and terrain data","authors":"W.C.-Y. Lee, D.J.Y. Lee","doi":"10.1109/VETECS.2000.851656","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851656","url":null,"abstract":"An accurate microcell prediction model needs to consider the effects of terrain contour and building factors on urban microcell radio propagation. An inexpensive and accurate way of executing this prediction is to utilize readily accessible street and terrain data as proposed in this paper. Various comparisons were done within the San Francisco Bay Area proving that the model calculations for the combination of attenuation from building and gain or loss from terrain (diffraction loss and effective antenna gains) encountered in the path of the mobile are fairly accurate. The street data utilized can be employed as either the base for creating the building database, or as a method of fine-tuning to improve the accuracy of the microcell model.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127245187","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851709
John M. Harris, Manish Airy
The primary function of the RLP is to reduce over the air frame error rate to a level tolerable by data services built over the CDMA air interface. When transmitting data, RLP is a pure NAK-based best effort selective repeat protocol. The main objective of this paper is to study the performance of the radio link protocol (RLP) as in IS 707 to support data services over the IS 95 CDMA physical layer. Since the RLP provides a stream-based in-sequence delivery of data to the upper layers, retransmissions of frames received in error cause delayed delivery of correctly received frames. This delay distribution is analytically characterized for the ARQ strategy used by the different versions of RLP (types 1, 2 and 3). Simulation results to verify the analytical model are also presented.
{"title":"Analytical model for radio link protocol for IS-95 CDMA systems","authors":"John M. Harris, Manish Airy","doi":"10.1109/VETECS.2000.851709","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851709","url":null,"abstract":"The primary function of the RLP is to reduce over the air frame error rate to a level tolerable by data services built over the CDMA air interface. When transmitting data, RLP is a pure NAK-based best effort selective repeat protocol. The main objective of this paper is to study the performance of the radio link protocol (RLP) as in IS 707 to support data services over the IS 95 CDMA physical layer. Since the RLP provides a stream-based in-sequence delivery of data to the upper layers, retransmissions of frames received in error cause delayed delivery of correctly received frames. This delay distribution is analytically characterized for the ARQ strategy used by the different versions of RLP (types 1, 2 and 3). Simulation results to verify the analytical model are also presented.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127282182","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851710
K. Jeong, J. Cheong, T. Park, T.G. Kim, S. Park
In this paper, we propose a formula to analyze the performance of the DS-CDMA reverse link according to the number, gain, and noise figure of the fiber-optic repeaters. The analytical approach is presented with the effects of other cells' interference. The capacity is not reduced even if adding the fiber-optic repeaters degrades the sensitivity of the base-station. Field test results are also presented to show that the fiber-optic repeaters improve coverage and quality in the weak CDMA coverage area.
{"title":"Performance analysis of DS-CDMA reverse link with fiber-optic repeaters","authors":"K. Jeong, J. Cheong, T. Park, T.G. Kim, S. Park","doi":"10.1109/VETECS.2000.851710","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851710","url":null,"abstract":"In this paper, we propose a formula to analyze the performance of the DS-CDMA reverse link according to the number, gain, and noise figure of the fiber-optic repeaters. The analytical approach is presented with the effects of other cells' interference. The capacity is not reduced even if adding the fiber-optic repeaters degrades the sensitivity of the base-station. Field test results are also presented to show that the fiber-optic repeaters improve coverage and quality in the weak CDMA coverage area.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127301731","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851523
T. Liew, L. Yang, L. Hanzo
Turbo decoded redundant residue number system (RRNS) codes are proposed and their performance is evaluated. An RRNS (n,k) code is a maximum-minimum distance block code, exhibiting identical distance properties to Reed-Solomon (RS) codes. Hence their error correction capability is given by t=(n-k)/2. We adapt the classic Chase algorithm in order to accept soft inputs and to provide soft outputs. Using the proposed soft input soft output (SISO) Chase algorithm, the turbo decoding of RRNS codes is contrived.
{"title":"Iterative decoding of redundant residue number system codes","authors":"T. Liew, L. Yang, L. Hanzo","doi":"10.1109/VETECS.2000.851523","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851523","url":null,"abstract":"Turbo decoded redundant residue number system (RRNS) codes are proposed and their performance is evaluated. An RRNS (n,k) code is a maximum-minimum distance block code, exhibiting identical distance properties to Reed-Solomon (RS) codes. Hence their error correction capability is given by t=(n-k)/2. We adapt the classic Chase algorithm in order to accept soft inputs and to provide soft outputs. Using the proposed soft input soft output (SISO) Chase algorithm, the turbo decoding of RRNS codes is contrived.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132947780","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 : 2000-05-15DOI: 10.1109/VETECS.2000.851236
R. Hoshyar, S. H. Jamali, A. Bahai
In transmission of the packets using OFDM (orthogonal frequency division multiplexing) system recommended by IEEE.802.11 there is a constraint on the interleaving depth due to the maximum allowable packet size and processing delay requirement. This results in a non-ideal interleaving which effectively limits the maximum achievable diversity from the channel. In such a channel, fading occurs in block wise manner, i.e., all transmitted symbols of the same block sense the same fade. Also, there is considerable correlation among the fade blocks. We call such a channel as correlated block fading (CBF) channel. With the excellent performance of turbo codes over AWGN, and ideally interleaved fading channels in mind, we tried to get similarly good performance by using turbo codes in OFDM packet transmission. We observed that the system severely suffers from the block fading behavior of the channel. A performance analysis is presented for CBF systems, and simulations for the OFDM system using rate 1/2 convolutional codes and turbo codes are performed. While the turbo code has no gain over the convolutional code with K=7 in BER (bit error rate) performance, it brings about 1.3 dB gain in PER (packet error rate) performance which is more important in packet transmission.
{"title":"Turbo coding performance in OFDM packet transmission","authors":"R. Hoshyar, S. H. Jamali, A. Bahai","doi":"10.1109/VETECS.2000.851236","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851236","url":null,"abstract":"In transmission of the packets using OFDM (orthogonal frequency division multiplexing) system recommended by IEEE.802.11 there is a constraint on the interleaving depth due to the maximum allowable packet size and processing delay requirement. This results in a non-ideal interleaving which effectively limits the maximum achievable diversity from the channel. In such a channel, fading occurs in block wise manner, i.e., all transmitted symbols of the same block sense the same fade. Also, there is considerable correlation among the fade blocks. We call such a channel as correlated block fading (CBF) channel. With the excellent performance of turbo codes over AWGN, and ideally interleaved fading channels in mind, we tried to get similarly good performance by using turbo codes in OFDM packet transmission. We observed that the system severely suffers from the block fading behavior of the channel. A performance analysis is presented for CBF systems, and simulations for the OFDM system using rate 1/2 convolutional codes and turbo codes are performed. While the turbo code has no gain over the convolutional code with K=7 in BER (bit error rate) performance, it brings about 1.3 dB gain in PER (packet error rate) performance which is more important in packet transmission.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"140 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130909178","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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