Public Safety Communication over 3GPP LTE

The 3rd Generation Partnership Project (3GPP) is ready to present a new cellular network standard; Long Term Evolution (LTE). LTE improves communication for public safety users like police, medical, and rescue workers in cellular networks. This creates a need to examine whether LTE can satisfy public safety users requirements. This thesis has a focus on group communication with a voice service. Using the LTE cellular network simulator we find the cell capacity and examine the performance at the capacity limit. We show that LTE can serve large groups for communication and by examining different voice activities we show there is only a small effect on capacity. With a study of optimization techniques we show that combining a low codec bit-rate with two bundled speech frames per IP packet gives a significant increase in capacity. By improving the scheduler algorithm by increasing the priority to old packets in the sending queue, we increase the capacity further. Based on the results from the evaluation we determine that LTE can satisfy the public safety users requirements, making LTE an option for public safety communication.