The first option - one favoured by Virgin 1215 - is to advertise the band width 105- 108 MHz (FM) as a fourth national radio network, available to 90 per cent of the population.
This would finally allow a commercial operator to set up a popular music channel on the last coveted FM freqeuncy likely to be freed for the private sector. It would be licensed to the highest bidder.
Virgin thinks its chances of success are hampered, with weekly audiences of around 3 million, because it does not have the right frequency to attract music lovers. Under a quirk of the Broadcasting Act the most desirable FM commercial frequency to come under the hammer so far went to a non-pop channel, Classic FM.
The Radio Authority says that UK listeners' choice would be enhanced, but by only one service. National advertisers might value the service, and it would redress the balance with the BBC.
However, it might impoverish existing independent local radio. The Radio Authority last year published a study showing how, in the short term, an advertising-financed Radio 1 would hit the development of commercial radio.
Other, more complicated options, include dividing up the frequencies to match existing commercial radio franchises, a move favoured by the industry, keen to protect its existing services. This means companies such as Capital Radio would be able to switch their 'classic gold' services from AM to the new FM frequency, provided the Government changed the ownership rules to comply.
A third option would carve up the national frequency into a lattice of small-scale services, ranging from community radio stations covering a radius of 10 kilometres to wider regional franchises.
A fourth option would provide a more diverse mixture of different sized stations, including three new ones around most cities, a chain of medium stations, and a number of small community stations.
The Radio Authority, which says it has a genuinely open mind, is inviting submissions by 22 April, and wants to make a decision this autumn.
Future Use of 105-108 MHz: A Consultative Document; the Press Office, The Radio Authority, Holbrook House, 14 Great Queen Street, London WC2B 5DG; Free.