UHF FM quasi-synchronous transmission system using site located atomic references

Abstract

When a quasi-synchronous transmission scheme, employing the use of aged, temperature controlled high stability crystal oscillators for RF carrier control, is used to provide large area radio coverage, one of the more demanding maintenance items is the periodic netting of the RF carriers; the period of such maintenance decreasing with increasing channel operating frequency. A technique is discussed which substantially reduces periodic netting of the RF carriers of a quasi-synchronous transmission system by the use of site located atomic references. The effect on voice communications integrity as a result of this technique is discussed, along with recommendations based on system performance during the initial 6 months of operation.