Mobile devices and their applications are continuing to develop and the more advanced they are, the more they require high data ranges and the more they demand of the available wireless communication networks. At present, LTE (Long Term Evolution) is a good solution as it provides the users of mobile devices with a good throughput and a low latency. In the future, the two most important aspects for end users will be system spectral efficiency and system power controlling. This thesis deals with LTE downlink spectral efficiency and power controlling. The thesis will show how, by using IP multicasting for the LTE downlink, the base station is able to provide the necessary data through a significantly smaller spectrum and, additionally, how cooperative diversity, i.e. the cooperation between several base stations, can improve or even maximise the total network channel capacity, regardless of bandwidth size. A Packet and Resource Plan Scheduling algorithm (PARPS) is used to schedule the transmissions, and the results are calculated in MATLAB. By this means it is possible to analyse the efficiency of the spectrum management, the coverage probability and the power controlling for the different transmitters used for the LTE downlink.The LTE downlink scheme is simulated in Matlab for different numbers of transmitters (2-3). IP multicasting over the LTE downlink manages to transmit the same amount of data using less transmission power (50- 66.6%) with a better system spectral efficiency.

In today’s DVB-T/H (Digital Video Broadcasting-Terrestrial/Handheld) systems, broadcasting is employed, meaning that TV programs are sent over all transmitters, also where there are no viewers. This is inefficient utilization of spectrum and transmitter equipment. IP multicasting is increasingly used for IP-TV over fixed broadband access. In this thesis, IP multicasting is proposed to also be used for terrestrial and mobile TV, meaning that TV programs are only transmitted where viewers have sent join messages over an interaction channel. This would substantially improve the system spectral efficiency (SSE) in (bit/s)/Hz/site, allowing reduced spectrum for the same amount of TV programs. It would even further improve the multiuser system spectral efficiency (MSSE – a measure defined in this study), allowing increased number of TV programs to be transmitted over a given spectrum. Further efficiency or coverage improvement, may be achieved by forming single-frequency networks (SFN), i.e. groups of adjacent transmitters sending the same signal simultaneously, on the same carrier frequency. The combination of multicasting and SFNs is also the principle of eMBMS (evolved Multicast Broadcast Multimedia Service) for cellular mobile TV over 4G LTE. PARPS (packet and resource plan scheduling) is an optimized approach to dynamically forming SFNs that is employed in this study. The target applications are DVB-T/H and eMBMS. Combining SFNs with non-continuous transmission (switching transmitters on and off dynamically) may give even further gain, and is used in LTE, but is difficult to achieve in DVB-T/H. Seven schemes are suggested and analyzed, in view to compare unicasting, multicasting and broadcasting, with or without SFN, with or without PARPS, and with or without continuous transmission. The schemes are evaluated in terms of coverage probability, SSE and MSSE. The schemes are simulated in MATLAB for a system of 4 transmitters, with random viewer positions. Zipf-law TV program selection is employed, using both a homogeneous and heterogeneous user behavior model. The SFN schemes provide substantially better system spectral efficiency compared to the multi-frequency networks (MFN) schemes. IP multicasting over non-continuous transmission dynamic SFN achieves as much as 905% and 1054% gain respectively in system spectral efficiency and multiuser system  spectral efficiency, from broadcasting over MFN, and 425% and 442% gain respectively from  IP multicasting over MFN, for heterogeneous fading case. Additionally, the SFN schemes gives a diversity gain of 3 dB over MFN, that may be utilized to increase the coverage probability by 4.35% for the same data rate, or to increase the data rate by 27 % for the same coverage as MFN.   Keywords: IP multicasting, broadcasting, coverage probability, system spectral efficiency, multiuser system spectral efficiency, DVB-T/H, eMBMS, mobile TV, IP-TV, SFN, MFN, Dynamic SFN, PARPS, homogeneous, heterogeneous, zipf-law