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Over the past three decades, the scientific and industrial communities have injected considerable resources into perfecting Orthogonal Frequency Division Multiplex (OFDM) — the driving technology behind many applications used today (such as IEEE 802.11g. Asymmetric Digital Subscriber Line (ADSL), and Digital Terrestrial Television). In 1997, OFDM was officially sanctioned for use in the European Telecommunications Standards Institute (ETSI) EN 300 744 standard known as Digital Video Broadcasting — Terrestrial (DVB-T). As OFDM is such a popular technology, there has been limited research over the years into alternatives. This paper will propose a novel approach to transmit parallel information through a terrestrial channel that could render it a more flexible alternative to OFDM in the future. Investigations have shown that this technique could provide a highly flexible, channel optimized modulation technique based on time-frequency multiplexing and this paper presents the preliminary phase of investigations into this new technique. [ABSTRACT FROM AUTHOR]

In 2002, the commercial digital terrestrial television service in the United Kingdom had a technological revival Since its first broadcast in 1998, there have been a number of reception issues concerning Digital Video Broadcasting - Terrestrial (DVB-T). As a result, the modulation method has changed in order to maximize the coverage and minimize errors. The consequence of changing the modulation method to a more robust system is that the overall throughput must suffer. Therefore, a trade-off between throughput and robustness must be made. This paper will detail the results of experiments performed to ascertain the justification of changing the modulation method in a DVB-T compliant system from 64-QAM to 16- QAM when transmitted at Radio Frequencies (RF) when subjected to multipath with long path delays as is normal in a Single Frequency Network (SFN). [ABSTRACT FROM AUTHOR]