Method for and apparatus to extract a frequency reference, a time reference and data from a single information system

A frequency reference, a time reference and data may be provided on, and subsequently extracted from, a single information stream. To achieve this a modulator 102 generates the single information stream by modulating the data on the frequency reference and pre-empting the data modulation to modulate the time reference on the frequency reference. This single information stream is then provided on a single bus 106 which is coupled to a plurality of base stations 103-105. The base stations 103-105 each include a demodulator 107-109, which recovers the frequency reference 117, the time reference 118, and/or the data 116, from the single information stream.