| 摘要 |
PCT No. PCT/FI93/00129 Sec. 371 Date Nov. 30, 1994 Sec. 102(e) Date Nov. 30, 1994 PCT Filed Mar. 30, 1993 PCT Pub. No. WO93/20619 PCT Pub. Date Oct. 14, 1993.An oscillator unit for a base station or the like in a digital cellular radio network. The oscillator unit includes an adjustable oven stabilized crystal oscillator (21). The oscillator unit additionally includes a non-volatile memory (27), in which is stored a control information defining the frequency of the oven stabilized crystal oscillator (21) at the start of the oscillator unit, apparatus (30, 31, 32) for deriving a reference frequency from a fixed digital transmission connection, such as a PCM connection, between the base station and the remaining cellular radio network, a frequency control loop (21, 22, 23, 24) for maintaining a long-term stability for the oven stabilized crystal oscillator (21) on the basis of a long-term average of the difference between the frequency of the oven stabilized crystal oscillator and the reference frequency. |
