llocated to the fixed, mobile, and radio- stations of other services are protected. determination services and the corresponding satellite services. It may be found expedient to allot whole bands, or sub-bands, to major civil users of radio. Thus the recognised providers of public telecommunications services may be authorised to use, Efficient spectrum utilisation and required to use efficiently, specified bands allocated to the fixed service. Other fixed service bands would be managed by 26.6.1 General measures the administration to provide frequency assignments for private fixed links. There are wise general principles of spectrum management, built Some bands allocated nationally for the land mobile service into the ITU Radio Regulations, supported by the recommendations may be designated for private mobile radio systems; others and reports of the International Radio Consultative Committee would be designated for radio telephones giving access to the (CCIR) and applied by administrations everywhere. These prin- Efficient spectrum utilisation 26/15 ciples enhance the value of radio as a communications medium, plan agreed in 1988 for the fixed satellite service (see Section increasing the information transmission capacity of the spectrum as 26.4.2.6). a whole and minimising link degradations due to interference. However, no rational and acceptable basis has ever been devised Attention is given to certain broad technical principles of spec- for sharing out a band between the nations. The actual requirements trum conserving system engineering. There are international stand- for which these reserved parcels of spectrum might ultimately be ards for the suppression of spurious emissions (ITU, 1990, assigned are not known at the time of planning and many may never Appendix 8). The bandwidth occupied by emissions is required to arise. And the systems, possibly few, that are established within the be limited to what is necessary. Frequency tolerances are applied to terms of such plans may be made more costly by the high 