{"title":"Performance evaluation of some hybrid ARQ schemes in IEEE 802.11a networks","authors":"E. Strinati, S. Simoens, J. Boutros","doi":"10.1109/VETECS.2003.1208890","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1208890","url":null,"abstract":"This paper investigates how a type II hybrid ARQ (HARQ) scheme combined with adaptive modulation and coding (AMC) can improve the throughput on top of the MAC layer, by comparing it to the existing type I HARQ + AMC mechanism in the IEEE 802.11a context. The studied type II HARQ+AMC strategy relies on incremental redundancy (IR) by use of rate compatible punctured codes as well as chase combining. The performance of the various strategies is mainly affected by two parameters. One of these is the inaccuracy of the link quality predictor, since the SNIR inherently fluctuates due to fading and interference; the other is the MAC overhead, which is especially important in IEEE 802.11a due to the CSMA/CA protocol. From the simulation results presented in this paper, it can be observed that even when MAC overhead is taken into account, the type II HARQ+AMC strategy still provides up to 1.5 dB gain with respect to current type I HARQ + AMC scheme.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125351136","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}
Takeo Ichikawa, Masataka Iizuka, M. Morikura, H. Matsui
{"title":"Wireless bridging and routing method employing a novel frame transfer protocol with shortcut","authors":"Takeo Ichikawa, Masataka Iizuka, M. Morikura, H. Matsui","doi":"10.1109/VETECS.2003.1207182","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207182","url":null,"abstract":"This paper presents a new wireless bridging and routing method for ad-hoc networks comprised of wireless bridges and/or wireless routers that comply with IEEE 802.11, a global standard for wireless LAN systems. This wireless bridging and routing method uses a novel frame transfer protocol with shortcut (FRASH) that we developed; that users can establish flexible and high speed ad-hoc wireless LANs easily at their offices and houses. This paper clarifies that the proposed bridging and routing method achieves higher throughput and less forwarding delay than the conventional transparent bridging protocol (TBP) by computer simulations, theoretical analysis, and experiments using a prototype wireless bridge and router device (WBR).","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125572340","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}
{"title":"Effective access scheme of reverse link in IP packet based satellite access network","authors":"T. Kwon, Kwangjae Lim, D. Cho","doi":"10.1109/VETECS.2003.1208798","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1208798","url":null,"abstract":"In this paper, we propose retransmission announced reservation multiple access (RARMA) scheme for multimedia services in satellite networks. In proposed scheme, resources are reserved according to the occasion demands by using spare reservation and released later using a distributed release scheme. We analyze the throughput and the delay of RARMA, verify them, and show that our proposed scheme maximizes the throughput and minimizes average packet delay, through analysis and computer simulation.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114883123","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}
Sanggee Kang, Unghee Park, Kyunghee Lee, Seongyoung Hong
{"title":"Adaptive feedforward amplifier using digital controller","authors":"Sanggee Kang, Unghee Park, Kyunghee Lee, Seongyoung Hong","doi":"10.1109/VETECS.2003.1207191","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207191","url":null,"abstract":"We designed and implemented a feedforward amplifier for WCDMA base station. The feedforward amplifier has the capability of adjusting the center frequency of linearization loops to get the better cancellation performance in the interesting frequency band. The controller detects the power of the pilot signal and the frequency of the pilot signal can be changed for the better cancellation performance in the interesting frequency band. The principles of control algorithm and the cancellation performance of the implemented feedforward amplifier are presented in this paper. The cancellation performance of the 1st loop is about 20 dB over 2110 MHz /spl sim/ 2170 MHz and 20 dB for the 2nd loop over 2090 MHz /spl sim/ 2190 MHz. For two-tone test the IMD cancellation performance is about 25 dB. For WCDMA signal, the cancellation performance is about 14 dB.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114925333","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}
{"title":"On the error probability performance of non-linearly distorted OFDM signals","authors":"M. Rodrigues, J. Mitchell, I. Darwazeh","doi":"10.1109/VETECS.2003.1207833","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207833","url":null,"abstract":"In this paper, we examine the error probability behavior on non-linearly distorted orthogonal frequency division multiplexing (OFDM) signals with different numbers of subchannels. Specifically, we show that for OFDM systems in the presence of non-linearities increasing the number of subchannels does not necessarily result in degradation of the error rate. We also show that the behavior of the error probability of non-linearly distorted OFDM signals is related to the properties of the intermodulation distortion (IMD) of such signals.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115531589","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}
{"title":"Quasi-optimum downlink power control of high altitude platform W-CDMA system","authors":"B. Ahmed, M. C. Ramón, L. Ariet","doi":"10.1109/VETECS.2003.1208836","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1208836","url":null,"abstract":"In this article, the performance of a quasi-optimum modified distance based downlink power control model is evaluated for high altitude platform station (HAPS) W-CDMA systems. We have generalized a previous model proposed by Gejji. Using our model, higher down link capacity is obtained.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"258 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116022295","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}
{"title":"Receiver-initiated multiple access protocols for spread spectrum mobile ad hoc networks","authors":"Yi-Sheng Su, S. Su, Jung-Shian Li","doi":"10.1109/VETECS.2003.1208844","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1208844","url":null,"abstract":"Two hybrid handshaking schemes based on the receiver-initiated concept and spread spectrum techniques are proposed for spread spectrum mobile ad hoc networks. In these schemes, called receiver-initiated multiple access common-transmitter-based (RIMA/C-T) and receiver-initiated multiple access receiver-transmitter-based (RIMA/R-T) protocols, the polling node allows the polled node to transmit a message to the polling node itself first after it acquires a channel successfully. The proposed schemes are the extension of previous works (M. Joa-Ng et al., April 1999). Under a general analytic model and assumptions, throughput and message delay of the proposed schemes are evaluated. Theoretical and simulation results show that the proposed schemes achieve better performance than multiple access with collision avoidance common-transmitter-based (MACA/C-T) and multiple access with collision avoidance common-transmitter-base (MACA/R-T) protocols proposed in earlier literature (M. Joa-Ng et al., April 1999).","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116032764","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}
{"title":"Simulations of communication systems via integrated variance reduction techniques","authors":"A. Bohdanowicz, J. Weber","doi":"10.1109/VETECS.2003.1208802","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1208802","url":null,"abstract":"This paper deals with efficiency issues of estimating common error performance measures of communication systems via Monte Carlo simulations. Efficient simulation techniques using integrated variance reduction techniques (VRTs) are proposed and studied. The integrated techniques are constructed by combining a number of basic VRTs. The general idea is that by integrating several basic VRTs their respective complementary properties can be exploited simultaneously, leading to additional variance reductions of the estimates and, consequently, to substantial gains in terms of simulation time required to obtain them. Based on the basic VRTs, two examples of the integrated techniques are presented and their performance is studied. Simulation results are provided to demonstrate the general approach of the integrated VRTs and to verify the concept. The results indicate that the simulation schemes based on the integrated VRTs can, indeed, improve the efficiency of the simulations. We argue that the great benefit of the integrated techniques is their potential of combining advantages and complementary features of the constituent basic VRTs. Thus, the integrated VRTs can achieve high efficiency gains even though the respective constituent basic VRTs do not operate under their optimal conditions, which is usually the case for a simulation scheme using a single VRT.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"55 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116384990","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}
{"title":"Artificial delay added space time turbo coding on OFDM in correlated fading channel","authors":"K. Miyoshi, M. Uesugi, O. Kato, A. Matsumoto","doi":"10.1109/VETECS.2003.1207851","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207851","url":null,"abstract":"This paper proposes an enhanced data transmission technique for space time turbo coding (STTuC) on OFDM. The performance of STTuC on OFDM degrades drastically when fading channel correlation between systematic stream and parity stream is high. Artificial delay added space time turbo coding (ADA-STTuC) lower the fading channel correlation between systematic and parity in high fading channel correlation case, which leads to performance improvement. Simulation results with two transmit antennas and one receiving antenna shows the performance improvement even in perfectly correlated fading channel.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122944714","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}
{"title":"Delay estimation for space-time coded signals over Rayleigh fading channels","authors":"Sang-Min Lee, Dong-Jo Park, Yeong-Hyeon Kwon","doi":"10.1109/VETECS.2003.1207635","DOIUrl":"https://doi.org/10.1109/VETECS.2003.1207635","url":null,"abstract":"This paper considers the space-time coded communication systems with two transmit antennas and one receive antenna. In high data rate communications, due to short symbol duration, the symbol delays in the channels between transmit antennas and a receive antenna can be different. In this case, intersymbol interference appears and Alamouti's scheme cannot be applied. Therefore, we proposed a new method to estimate the channel delays and to decode the received signals by using the estimated delays. The effectiveness of the proposed method is demonstrated through simulations.","PeriodicalId":272763,"journal":{"name":"The 57th IEEE Semiannual Vehicular Technology Conference, 2003. VTC 2003-Spring.","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123017264","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}