Search

This paper analyses the behavior of two hybrid time-code division multiple-access (T/CDMA) architectures on the up-link of a macrocellular mobile radio system. For the examined schemes two categories of users-voice and data-share the domain of available resources, made up of time slots and codewords, through two alternative assignment strategies. Both solutions attribute voice users one single resource pair, i.e., one time slot and a single code to employ on that time slot, but differ in the way data users requests are accommodated: they are either simultaneously granted several codes over the same time slot or are assigned a single code over several distinct time slots. Call admission control is performed by a channel assignment algorithm which dynamically attributes resources only if specified levels of transmission quality are met on the radio channels. The blocking and the outage probability of the two classes of users are determined and compared, showing that one of the proposed schemes exhibits better performance and allows to satisfyingly serve a significant percentage of data users [ABSTRACT FROM PUBLISHER]

This letter determines the capacity of a TDD-TD/CDMA architecture which supports different classes of subscribers and adopts an interference-driven admission control policy. The blocking probabilities of the system users are evaluated under various traffic conditions for several uplink/downlink configurations of the time slots, demonstrating that the time division full duplex approach needs careful tuning in order to maximize system capacity [ABSTRACT FROM PUBLISHER]

This letter analyzes the behavior of two time-code division architectures serving voice and data applications on the uplink of a cellular radio system. Both solutions attribute speech users one code over a timeslot, whereas data users are granted several codes over the same timeslot or a single code over several time slots. Call admission control dynamically attributes resources if specified levels of transmission quality are met. The blocking probability of the two classes of users is determined, demonstrating that the multicode T/CDMA approach performs better than the multislot solution and than a pure CDMA system [ABSTRACT FROM PUBLISHER]