摘要:

The equilibrium behaviour of store-and-forward packet-switched networks is studied under realistic conditions via a network of queues. A network with a general mesh topology is considered. Switching nodes have a finite number of store-and-forward buffers, and communication channels are not perfect. A node-node protocol with positive acknowledgment and retransmission is modelled, and consumes part of the channel buffers. A new approach is employed to obtain buffer overflow probabilities using a truncated multiserver queue with channel buffers being both the servers and the storage places. The developed model accounts explicitly for the acknowledgment delays and interactions among adjacent queues. The principal results are mean buffer size and overflow probability, retransmission probability and the mean delays as functions of the number of buffers, traffic levels and the error rate of data transfer. The developed model is validated by comparison with simulation results.

DOI:10.1049/ip-f-1.1987.0014

出版商:IEE    

年代:1987

数据来源: IET

摘要:

A cellular hand-off treatment based on cell membership degrees is presented. The proposed method permits the systematic incorporation of a variety of different weight criteria. An example of application is given, and it is shown that the procedure leads to a low number of handoffs without excessive cell coverage overlapping. If one of the criteria is derived from traffic levels, then traffic imbalance may be reduced without recourse to channel borrowing.

DOI:10.1049/ip-f-1.1987.0015

出版商:IEE    

年代:1987

数据来源: IET

摘要:

The paper presents a new approach to improve the detection and tracking performance of a track-while-scan (TWS) radar. The contribution consists of three parts. In Part 1 the scope of various papers in this field is reviewed. In Part 2, a new approach for integrating the detection and tracking functions is presented. It shows howa prioriinformation from the TWS computer can be used to improve detection. A new multitarget tracking algorithm has also been developed. It is specifically oriented towards solving the combinatorial problems in multitarget tracking. In Part 3, analytical derivations are presented for quantitatively assessing,a priori, the performance of a track-while-scan radar system (true track initiation, false track initiation, true track continuation and false track deletion characteristics). Simulation results are also shown.

DOI:10.1049/ip-f-1.1987.0016

出版商:IEE    

年代:1987

数据来源: IET

摘要:

The paper presents, in three parts, a new approach to improve the detection and tracking performance of a track-while-scan (TWS) radar. Part 1 presents a review of current status. In this part, Part 2, it is shown how the detection can be improved by utilising information from tracker. A new multitarget tracking algorithm, capable of tracking manoeuvring targets in clutter, is then presented. The algorithm is specifically tailored so that the solution to the combinatorial problem presented in a companion paper can be applied. The implementation aspects are discussed and a multiprocessor architecture identified to realise the full potential of the algorithm. Part 3 presents analytical derivations for quantitative assessment of the performance of the TWS radar system. It also shows how the performance can be optimised.

DOI:10.1049/ip-f-1.1987.0017

出版商:IEE    

年代:1987

数据来源: IET

摘要:

The paper presents, in three parts, a new approach to improve the detection and tracking performance of a track-while-scan radar. Part 1 presents a review of the current status of the subject. Part 2 details the new approach. It shows howa prioriinformation provided by the tracker can be used to improve detection. It also presents a new multitarget tracking algorithm. In the present Part, analytical derivations are presented for assessing,a priori, the performance of the TWS radar system. True track initiation, false track initiation, true track continuation and false track deletion characteristics have been studied. It indicates how the various thresholds can be chosen by the designer to optimise performance. Simulation results are also presented.

DOI:10.1049/ip-f-1.1987.0018

出版商:IEE    

年代:1987

数据来源: IET

摘要:

The paper presents a new solution to the combinatorial problems that arise when multiple targets are to be tracked simultaneously. In multitarget situations, the correspondence between targets and observations may be lost because of crossing trajectories, close-by targets, false alarms, missed detections etc. The number of data association hypotheses that are feasible and for which probabilities have to be calculated is extremely large in any but the smallest of such problems. We present a new algorithm for locating theNglobally best hypotheses using a simple search method instead of extensive enumeration or integer programming methods.

DOI:10.1049/ip-f-1.1987.0019

出版商:IEE    

年代:1987

数据来源: IET