Capacity comparison of an OFDM based multiple access system using different dynamic resource allocation

A future mobile communication system must support not only the traditional speech service but also other services such as multimedia, circuit switched and packet based data. Though no “killer application” is known today the system design must be flexible enough to simultaneously handle different types of services (circuit switched and packet based), with different demands on quality of service (blocking, delay and throughput). Efficient handling of different mixtures of services must be a key issue, for a high capacity system. This work has been done in connection with the evaluation of candidates for the European, Universal Mobile Telecommunication System (UMTS). The paper studies what effects a mixed service scenario would give on the capacity of the cellular system, using different types of resource allocation. The different profiles of the services, in combination with the large amount of freedom regarding user behaviour, motivates scenario simulations. Two scenarios (speech and circuit switched data dominated) are studied. The performance is compared for different types of resource allocation schemes, in an OFDM based multiple access system. In OFDM, all resources are available in all cells as the FFT works on the total available bandwidth. This makes a multiple access system based on OFDM suitable for using together with dynamic resource allocation