ISSN:1124-318X    

DOI:10.1002/ett.4460050102

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

ISSN:1124-318X    

DOI:10.1002/ett.4460050103

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

ISSN:1124-318X    

DOI:10.1002/ett.4460050104

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

ISSN:1124-318X    

DOI:10.1002/ett.4460050105

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

ISSN:1124-318X    

DOI:10.1002/ett.4460050106

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractMobile wireless communications, which includes cellular telephones, land mobile radio, and personal communication systems, have experienced enormous growth over the last decade. Data services represent a critical component of future wireless communications, but have received little attention. While some attention has been given to specialized mobile data networks, less has been directed at the ongoing design of data services in evolving digital cellular networks. In this paper we report on the results of a simulation study which explores voice‐data integration performance in third generation wireless communication networks. These networks are designed to provide access to broadband ISDN networks for large numbers of mobile voice and data users. The primary goal of the paper is the development of multiple access transmission protocols that will enable the voice and data terminals to efficiently share the terminal to base station wireless channel. Reservation Random Access (RRA) protocols are used for voice traffic, and multiple random access contention protocols are used for data traffic. The RRA protocols used enable the data terminals to precisely determine the end of voice packet contention periods, therefore providing a natural separation between voice and data contention. Such voice data integration mechanisms allow the voice contending terminals to resolve their contention without any interference from the data terminals. Data contention resolution does not degrade the voice performance, since it follows the voice contention resolution. The above approach is a promising alternative to other existing proposals due to its superior data packet throughput‐delay performance under steady state, and voice performance under transient conditions. Our results show that dispersed voice and data terminals can efficiently share a wireless chan

ISSN:1124-318X    

DOI:10.1002/ett.4460050107

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractIn this paper we study the performance of tree‐like splitting collision resolution algorithms in channels with markovian capture. In particular, we assume that in each slot the channel can be in one of two states ‐b(for “bad”) andg(for “good”). When the channel is in stateb, a capture can never occur. When the channel is in stategandnnodes (n ≥ 2) are transmitting, a capture occurs with probability πn. The sequence of channel states is assumed to be a homogeneous Markov chain. We derive the throughput of a splitting tree‐like multiple access algorithm for this channel. We also provide simulation results for t

ISSN:1124-318X    

DOI:10.1002/ett.4460050108

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractDirect‐Sequence Spread Spectrum Multiple Access (DS‐SSMA) techniques are being proposed for modern personal and mobile radio communication networks. Fast and accurate acquisition of synchronism between the received code sequence and the locally generated sequence plays a fundamental role in the successful utilization of any code division multiple access technique. In this paper, the performance of the code acquisition sub‐system is analysed in the presence of multiple access interference, data modulation and noise. The effect of interference from other codes is analysed without resorting to a Gaussian approximation; this approach allows the evaluation of the properties of different families of codes. Results of the analysis are presented for Maximal Length Shift Register (MLSR), Gold and Kasami sequences, with and without verification mode, with absorbing and non absorbing false alarm

ISSN:1124-318X    

DOI:10.1002/ett.4460050109

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractIn the present paper, channel estimation in the uplink of CDMA mobile radio systems with burst transmission applying joint detection is considered. The different radio channels are estimated at the receiver using known midamble codes. Either maximum‐likelihood, i.e. optimum, or suboptimum channel estimation can be realized at the receiver. Several methods for constructing code sets for the simultaneously active users are proposed. It is shown that the structure of the channel estimator for a multi‐user synchronous CDMA mobile radio system is the same as for a single‐user system when the mid amble codes of the users are segments derived from a single basic code. Furthermore, it is shown that the channel estimator can be implemented as a correlator when the midamble codes are constructed from a periodic basic code. Finally, the effect of noisy channel estimation, i.e. the presence of channel estimation errors, on the detected data is exa

ISSN:1124-318X    

DOI:10.1002/ett.4460050110

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY

摘要:

AbstractSome different packet protocols, based on a Reservation ALOHA protocol, have been proposed in literature for use in mobile radio systems, even though their performance have been fully evaluated only in interference free environments. The paper focuses on Packet Reservation Multiple Access (PRMA) and extends the evaluation of its performance to a cellular environment, first by characterising its performance when loaded by a Poisson traffic distribution and then assessing the impact of interference from other cells.

ISSN:1124-318X    

DOI:10.1002/ett.4460050111

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1994

数据来源: WILEY