cy DVB-T network. Although the LTE MBSFN is described as a single frequency network, it could be deployed as a cluster of SFN enhanced node B base stations with frequency reuse from cluster to cluster. Present standards work is focused on either FDD or TDD implementation, known as down- link optimised broadcasting within existing cellular allocations, for example the TDD bands within Band I at 2 GHz. Making Telecoms Work 15.18.2 MBSFN Investment Incentive - Cost Saving and Revenue Opportunities This, however, fails to capitalise on some potential major cost saving and enhanced revenue opportunities that together could provide the required incentives for MBSFN investment. These can be identified by analysing the problems that the broadcasting and cellular industry have to solve, some of which we have identified earlier. As can be seen from the table, the 8-k subcarrier OFDM used in DVB-T allows large cells to be deployed. This means that DVB-T broadcast networks can be very cost economic. However, to provide adequate coverage, low-power infill sites have to be deployed that add capital cost and running cost and reduce broadcast spectral efficiency. Although this provides adequate coverage at an adequate link budget for TVs (including high-definition TVs) with a roof-top aerial, there is generally not enough signal strength to support portable receivers. Portable TV receivers have been the Cinderella of the TV industry for many years but the availability of lap tops with DVB or ATSC modems will potentially result in a much broader market reach. The top of the range high-definition Sony Vaio 16 is one example. However, the signal levels in most countries are not sufficient to deliver a sufficiently consistent user experience to support mass-market adoption. Deployment of high-density SFNs based on existing cellular infrastructure would overcome this problem. The difficulty is that portable DVB devices do not work well unless connected to an outdoor aerial or a satellite dish or cable. These limit the portability of 