I am aware of the Iridium satellite communications system and of a number of other similar systems which are being developed. I understand the Iridium satellite communications system has been licensed by the Director of Telecommunications Regulation to provide services in Ireland. While such systems are capable of providing global coverage, it is not expected that demand for their services would be such as to render current terrestrial mobile phone systems or the masts associated with them redundant. Currently, calls made on satellite communications services are, in general, more expensive. In addition, while the technology is improving, the phone handsets associated with these systems are larger and heavier and are also more expensive. One of the features of these systems is that the frequencies at which they operate are higher than the terrestrial mobile telephony frequencies. Consequently, penetration of the signal through buildings is less successful and indoor coverage equivalent to what is achieved by terrestrial mobile systems may be difficult to match.
Another point is that the amount of radio frequency spectrum available to these services is not sufficient to accommodate all of the day-to-day traffic requirements of mobile phone users in developed urban areas. Because of this limited amount of spectrum, it is envisaged that satellite operators will negotiate roaming agreements with terrestrial mobile operators so that many calls made to or from a satellite communications system will be carried at least partly on a terrestrial system.