The Telecommunications Handbook: Engineering Guidelines for Fixed, Mobile and Satellite Systems

11.11 DLDC

11.11.1 Installation Aspects

The DLDC feature of offers a possibility to enhance the data rates of DLDC-capable MSs by increasing the number of radio timeslots that can be allocated for the downlink TBFs of such mobiles. This is achieved by assigning the resources of an EGPRS downlink TBF on two TRXs. The MS receives both radio frequency channels, thus doubling downlink throughput. An uplink TBF, on the other hand, is assigned on one TRX only. However, the UL TBF can be dynamically reallocated between the two TRXs to maximize utilization of uplink resources. This feature doubles downlink peak throughput, bringing rates of up to 592 kb/s. The average throughput can exceed 300 kb/s, enabling for example, the streaming of high quality video.

Typically, DLDC activation is done per BTS. In order to enable DLDC in a BTS, EGPRS must be enabled, and the DLDC license must have enough capacity available. The DLDC functionality might require update to the PCU version. The default EGPRS capacity must be configured on two TRXs which are in the same EDAP in order to serve DLDC-capable mobile stations with a DLDC configuration. Depending on the vendor solutions, DLDC might require the activation of also other features in order to exploit the extended multislot capabilities of MSs with multislot classes 30–45 for DLDC.

11.11.2 Time Slot Allocation

The time slot territory changes due to the increasing and decreasing of the voice and other data users. The territory strategy depends ...