Pub Date : 2000-12-13DOI: 10.1109/VETECS.2000.851426
Jianjun Wu, K. Samaras, C. Demetrescu, R. Yan
A method to transmit the voice over an EDGE system is proposed. New radio link control (RLC)/medium access control (MAC) headers are proposed. To increase the reliability of RLC/MAC headers, an error detection and correction scheme is proposed. The simulation results show that between 12/spl sim/30% RLC/MAC can be saved due to our new method. The system capacity is increased significantly for voice transmission over a packet switched EDGE network compared to traditional circuit switched network such as GSM. To avoid the extra delay introduced by normal packet switch networks, a fast access mechanism for uplink transmission is introduced to guarantee the quality of service for voice.
{"title":"Transmission of voice in an EDGE network","authors":"Jianjun Wu, K. Samaras, C. Demetrescu, R. Yan","doi":"10.1109/VETECS.2000.851426","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851426","url":null,"abstract":"A method to transmit the voice over an EDGE system is proposed. New radio link control (RLC)/medium access control (MAC) headers are proposed. To increase the reliability of RLC/MAC headers, an error detection and correction scheme is proposed. The simulation results show that between 12/spl sim/30% RLC/MAC can be saved due to our new method. The system capacity is increased significantly for voice transmission over a packet switched EDGE network compared to traditional circuit switched network such as GSM. To avoid the extra delay introduced by normal packet switch networks, a fast access mechanism for uplink transmission is introduced to guarantee the quality of service for voice.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130810717","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 : 2000-12-03DOI: 10.1109/VETECS.2000.851255
C. Rose, S. Ulukus, R. Yates
Motivated by the emergence of programmable radios, we seek to understand a new class of communication system where pairs of transmitters and receivers can adapt their modulation/demodulation method in the presence of interference to achieve better performance. Using the signal to interference ratio as a metric and a general signal space approach, we present a class of iterative distributed algorithms for synchronous systems which results in an ensemble of optimal waveforms for multiple users connected to a common receiver (or co-located independent receivers). That is, the waveform ensemble meets the Welch (1974) bound with equality and therefore achieves minimum average interference over the ensemble of signature waveforms. We describe fixed points for a number of scenarios.
{"title":"Interference avoidance for wireless systems","authors":"C. Rose, S. Ulukus, R. Yates","doi":"10.1109/VETECS.2000.851255","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851255","url":null,"abstract":"Motivated by the emergence of programmable radios, we seek to understand a new class of communication system where pairs of transmitters and receivers can adapt their modulation/demodulation method in the presence of interference to achieve better performance. Using the signal to interference ratio as a metric and a general signal space approach, we present a class of iterative distributed algorithms for synchronous systems which results in an ensemble of optimal waveforms for multiple users connected to a common receiver (or co-located independent receivers). That is, the waveform ensemble meets the Welch (1974) bound with equality and therefore achieves minimum average interference over the ensemble of signature waveforms. We describe fixed points for a number of scenarios.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124013360","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 : 2000-11-15DOI: 10.1109/VETECS.2000.851364
Hwa-Chun Lin, Show-Shiow Tzeng
In this paper, we propose a call admission control policy for cluster-based micro/picocellular wireless networks. The proposed call admission policy employs two levels of admission thresholds: one at the cluster level and the other at the cell level. The performance of the proposed policy is compared with that of the policy proposed by Naghshineh et al. (see J. High-Speed Networks, vol.4, no.5, p.53-71, 1996). Our results show that, under the condition that both policies provide the same predetermined maximum level of call hand-off dropping probability, the proposed call admission policy provides significantly lower call handoff dropping probability and significantly higher call success probability and throughput than the policy proposed previously.
{"title":"Double-threshold admission control in cluster-based micro/picocellular wireless networks","authors":"Hwa-Chun Lin, Show-Shiow Tzeng","doi":"10.1109/VETECS.2000.851364","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851364","url":null,"abstract":"In this paper, we propose a call admission control policy for cluster-based micro/picocellular wireless networks. The proposed call admission policy employs two levels of admission thresholds: one at the cluster level and the other at the cell level. The performance of the proposed policy is compared with that of the policy proposed by Naghshineh et al. (see J. High-Speed Networks, vol.4, no.5, p.53-71, 1996). Our results show that, under the condition that both policies provide the same predetermined maximum level of call hand-off dropping probability, the proposed call admission policy provides significantly lower call handoff dropping probability and significantly higher call success probability and throughput than the policy proposed previously.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134257817","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 : 2000-05-20DOI: 10.1109/VETECS.2000.851492
S. Bhashyam, A. Hottinen
This paper studies the performance of iterative multiuser decoding, interference cancellation, and channel estimation techniques applicable to third generation WCDMA systems. The concept uses a posteriori probabilities of code symbols to enhance detection, decoding and channel estimation in an iterative fashion. The performance is analyzed in a multipath channel with simulations. It is seen that the proposed concept combats multiuser interference effectively and performs almost as well as single user systems.
{"title":"Performance of iterative multiuser decoding and channel estimation in WCDMA systems","authors":"S. Bhashyam, A. Hottinen","doi":"10.1109/VETECS.2000.851492","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851492","url":null,"abstract":"This paper studies the performance of iterative multiuser decoding, interference cancellation, and channel estimation techniques applicable to third generation WCDMA systems. The concept uses a posteriori probabilities of code symbols to enhance detection, decoding and channel estimation in an iterative fashion. The performance is analyzed in a multipath channel with simulations. It is seen that the proposed concept combats multiuser interference effectively and performs almost as well as single user systems.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124614702","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.2000.851505
J. Wey, Wei-Pang Yang, S. Tseng
The electronic toll collection system is widely applied to payment collection oo the freeway all over the world. We derive the relationship of the coverage length of the toll collection area m, the vehicle velocity v, and the mean vehicle residence time 1//spl eta/. In addition, the processing time of the client system is bounded by the factors of the mean vehicle dwell time, the propagation delay, and the transmission time. The upper bound of the server response time is calculated from the mean response time of the client system, the propagation delay, the transmission time, and the mean vehicle dwell time. Furthermore, the statistical probability bound for the response time performance of the server has been defined by the specified response time for the client system and the acceptable significance level of loss of service p in advance. Finally, the M/M/z queueing simulation estimates the number of server z required for the stringent performance requirement.
{"title":"On estimating the coverage length of toll collection area and client-server response time","authors":"J. Wey, Wei-Pang Yang, S. Tseng","doi":"10.1109/VETECS.2000.851505","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851505","url":null,"abstract":"The electronic toll collection system is widely applied to payment collection oo the freeway all over the world. We derive the relationship of the coverage length of the toll collection area m, the vehicle velocity v, and the mean vehicle residence time 1//spl eta/. In addition, the processing time of the client system is bounded by the factors of the mean vehicle dwell time, the propagation delay, and the transmission time. The upper bound of the server response time is calculated from the mean response time of the client system, the propagation delay, the transmission time, and the mean vehicle dwell time. Furthermore, the statistical probability bound for the response time performance of the server has been defined by the specified response time for the client system and the acceptable significance level of loss of service p in advance. Finally, the M/M/z queueing simulation estimates the number of server z required for the stringent performance requirement.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"146 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":"115241625","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.2000.851527
S. Yeom, P. Park, Yongwan Park
We introduce a modified interference cancellation scheme to overcome MAI (multiple access interference) in DS-CDMA. Among the ICs (interference cancellers), the PIC (parallel interference canceller) requires more stages to have the better BER, and the SIC (successive interference canceller) faces the problems of power reordering and large delays. To resolve these problems, we propose a modified interference cancellation scheme combining SIC and PIC. The proposed IC has improved the performance through the total received signal applied ranking method is fed into the initial stage. Its structure extracts the good characteristics because of the MAI removed from the input signal in the initial stage. The characteristics of the proposed system are as follows: (1) smaller delay, (2) the MAI in the strongest user signal is also reduced (unlike SIC), (3) it has a good BER performance using fewer stages (unlike PIC).
{"title":"Evaluation of parallel interference cancellation with the advanced first-stage in Rayleigh-fading channels","authors":"S. Yeom, P. Park, Yongwan Park","doi":"10.1109/VETECS.2000.851527","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851527","url":null,"abstract":"We introduce a modified interference cancellation scheme to overcome MAI (multiple access interference) in DS-CDMA. Among the ICs (interference cancellers), the PIC (parallel interference canceller) requires more stages to have the better BER, and the SIC (successive interference canceller) faces the problems of power reordering and large delays. To resolve these problems, we propose a modified interference cancellation scheme combining SIC and PIC. The proposed IC has improved the performance through the total received signal applied ranking method is fed into the initial stage. Its structure extracts the good characteristics because of the MAI removed from the input signal in the initial stage. The characteristics of the proposed system are as follows: (1) smaller delay, (2) the MAI in the strongest user signal is also reduced (unlike SIC), (3) it has a good BER performance using fewer stages (unlike PIC).","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"31 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":"115455628","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.2000.851429
K. Chawla, P. Driessen, X. Qiu
We investigate the feasibility of transmitting MPEG-2 AAC (Advanced Audio Coder) music over packet-switched bearers of an Enhanced General Packet Radio Services cellular network. Streaming data applications like AAC music differ from conversational voice in that they permit a larger transmission delay and delay jitter than the former. In addition, AAC music can tolerate a higher frame error rate than voice by using error concealment techniques at the receiver. This creates the opportunity to transmit AAC music over data-optimized, high-throughput and nominally high-error rate, wireless networks, by using appropriate performance enhancing techniques. In particular, we investigate the performance with the following techniques: (i) link-layer retransmissions; (ii) dynamic packet assignment; and (iii) packet interleaving or shuffling. We find that all the above techniques are desirable in order to simultaneously achieve a high spectral efficiency and the required quality. While this paper is focused on one application, the conclusions and insights are applicable to most streaming audio and video applications.
{"title":"Transmission of streaming data over an EGPRS wireless network","authors":"K. Chawla, P. Driessen, X. Qiu","doi":"10.1109/VETECS.2000.851429","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851429","url":null,"abstract":"We investigate the feasibility of transmitting MPEG-2 AAC (Advanced Audio Coder) music over packet-switched bearers of an Enhanced General Packet Radio Services cellular network. Streaming data applications like AAC music differ from conversational voice in that they permit a larger transmission delay and delay jitter than the former. In addition, AAC music can tolerate a higher frame error rate than voice by using error concealment techniques at the receiver. This creates the opportunity to transmit AAC music over data-optimized, high-throughput and nominally high-error rate, wireless networks, by using appropriate performance enhancing techniques. In particular, we investigate the performance with the following techniques: (i) link-layer retransmissions; (ii) dynamic packet assignment; and (iii) packet interleaving or shuffling. We find that all the above techniques are desirable in order to simultaneously achieve a high spectral efficiency and the required quality. While this paper is focused on one application, the conclusions and insights are applicable to most streaming audio and video applications.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"1 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":"115620223","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.2000.851257
Hwa-Chun Lin, Ping-Chin Fung
This paper proposes a new method for finding the available bandwidth of a path in multihop mobile wireless networks. The proposed method finds the link with the minimum current bandwidth and increases its bandwidth. This process is repeated until the bandwidth of the link with the smallest current bandwidth cannot be increased. Then the available bandwidth of the path is found to be the minimum of the current bandwidths of the links along the path. Extensive simulations are performed to compare the performance of the proposed method and that of the method which calculates the path bandwidth hop by hop. Our simulation results show that using the proposed method in a multihop mobile wireless network produces significantly lower call blocking ratio than the method which calculates the path bandwidth hop by hop.
{"title":"Finding available bandwidth in multihop mobile wireless networks","authors":"Hwa-Chun Lin, Ping-Chin Fung","doi":"10.1109/VETECS.2000.851257","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851257","url":null,"abstract":"This paper proposes a new method for finding the available bandwidth of a path in multihop mobile wireless networks. The proposed method finds the link with the minimum current bandwidth and increases its bandwidth. This process is repeated until the bandwidth of the link with the smallest current bandwidth cannot be increased. Then the available bandwidth of the path is found to be the minimum of the current bandwidths of the links along the path. Extensive simulations are performed to compare the performance of the proposed method and that of the method which calculates the path bandwidth hop by hop. Our simulation results show that using the proposed method in a multihop mobile wireless network produces significantly lower call blocking ratio than the method which calculates the path bandwidth hop by hop.","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":"115728973","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.2000.851368
B. Cho, H. Lim, Jae-chul Song, Dae-Jin Kim
We propose a method using coherent detection with a time division multiple pilot signal for each user in the reverse CDMA channel as the structure of reverse CDMA channel to apply CDMA to the upstream channel of bidirectional LMDS. By using coherent detection with a pilot signal in the reverse CDMA channel, the capacity can be improved when compared with noncoherent detection, but it is required to allocate a pilot signal for all users. Also, the interference is increased due to the need to continuously allocate the pilot signals. In this case the channel capacity is decreased. A method of pilot allocation is needed that reduce this interference and keep the synchronization effect using coherent detection. In the reverse link, where the pilot is allocated to each user at a different time and not overlapped is possible solution. This pilot is proposed, and its performance and capacity analyzed. The result is that the proposed method has a greater increased capacity compared with others.
{"title":"A new upstream channel structure for asymmetric LMDS with CDMA","authors":"B. Cho, H. Lim, Jae-chul Song, Dae-Jin Kim","doi":"10.1109/VETECS.2000.851368","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851368","url":null,"abstract":"We propose a method using coherent detection with a time division multiple pilot signal for each user in the reverse CDMA channel as the structure of reverse CDMA channel to apply CDMA to the upstream channel of bidirectional LMDS. By using coherent detection with a pilot signal in the reverse CDMA channel, the capacity can be improved when compared with noncoherent detection, but it is required to allocate a pilot signal for all users. Also, the interference is increased due to the need to continuously allocate the pilot signals. In this case the channel capacity is decreased. A method of pilot allocation is needed that reduce this interference and keep the synchronization effect using coherent detection. In the reverse link, where the pilot is allocated to each user at a different time and not overlapped is possible solution. This pilot is proposed, and its performance and capacity analyzed. The result is that the proposed method has a greater increased capacity compared with others.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"23 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":"125234615","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.2000.851643
A. Sadri, T. Eyceoz, W. Alexander
This paper proposes novel adaptive power control and rate change schemes and investigates the performance of a wideband code division multiple access (W-CDMA) system in conjunction with these adaptive techniques. In these schemes, the power and rate are adapted to the variations of the fading channel as forecasted by a novel long-range prediction algorithm. This algorithm characterizes the channel as an autoregressive model with lower channel sampling rate compared to the conventional data rate methods of fading estimations. The performance of this scheme is evaluated using a detailed block diagram simulation of a W-CDMA system. All major components of the system are modeled and simulated, including an accurate model for realistic mobile channels. The performance of these systems is compared to that of a system without adaptive power and rate control. The proposed novel scheme is superior to the traditional approach of transmitter power control and rate change based on the channel estimation and signal to interference calculation at the receiver.
{"title":"Novel adaptive transmitter power and rate control schemes for W-CDMA systems","authors":"A. Sadri, T. Eyceoz, W. Alexander","doi":"10.1109/VETECS.2000.851643","DOIUrl":"https://doi.org/10.1109/VETECS.2000.851643","url":null,"abstract":"This paper proposes novel adaptive power control and rate change schemes and investigates the performance of a wideband code division multiple access (W-CDMA) system in conjunction with these adaptive techniques. In these schemes, the power and rate are adapted to the variations of the fading channel as forecasted by a novel long-range prediction algorithm. This algorithm characterizes the channel as an autoregressive model with lower channel sampling rate compared to the conventional data rate methods of fading estimations. The performance of this scheme is evaluated using a detailed block diagram simulation of a W-CDMA system. All major components of the system are modeled and simulated, including an accurate model for realistic mobile channels. The performance of these systems is compared to that of a system without adaptive power and rate control. The proposed novel scheme is superior to the traditional approach of transmitter power control and rate change based on the channel estimation and signal to interference calculation at the receiver.","PeriodicalId":318880,"journal":{"name":"VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026)","volume":"112 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":"116639503","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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