Computer Science – Information Theory
Scientific paper
2007-05-23
Computer Science
Information Theory
To be published on IEEE Transactions on Information Theory
Scientific paper
In random-access communication systems, the number of active users varies with time, and has considerable bearing on receiver's performance. Thus, techniques aimed at identifying not only the information transmitted, but also that number, play a central role in those systems. An example of application of these techniques can be found in multiuser detection (MUD). In typical MUD analyses, receivers are based on the assumption that the number of active users is constant and known at the receiver, and coincides with the maximum number of users entitled to access the system. This assumption is often overly pessimistic, since many users might be inactive at any given time, and detection under the assumption of a number of users larger than the real one may impair performance. The main goal of this paper is to introduce a general approach to the problem of identifying active users and estimating their parameters and data in a random-access system where users are continuously entering and leaving the system. The tool whose use we advocate is Random-Set Theory: applying this, we derive optimum receivers in an environment where the set of transmitters comprises an unknown number of elements. In addition, we can derive Bayesian-filter equations which describe the evolution with time of the a posteriori probability density of the unknown user parameters, and use this density to derive optimum detectors. In this paper we restrict ourselves to interferer identification and data detection, while in a companion paper we shall examine the more complex problem of estimating users' parameters.
Biglieri Ezio
Lops Marco
No associations
LandOfFree
Multiuser detection in a dynamic environment Part I: User identification and data detection does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Multiuser detection in a dynamic environment Part I: User identification and data detection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multiuser detection in a dynamic environment Part I: User identification and data detection will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-401751