| 摘要 |
PCT No. PCT/FI92/00176 Sec. 371 Date Feb. 5, 1993 Sec. 102(e) Date Feb. 5, 1993 PCT Filed Jun. 5, 1992 PCT Pub. No. WO92/22963 PCT Pub. Date Dec. 23, 1992.The base station includes for monitoring the quality of a radio link between the base station and mobile stations, a generator (1, 2, 3) for generating a square wave signal (CK) having a monitoring signal frequency; and a filter (4) for generating a monitoring signal (CS) from the square wave signal (CK). The frequency of the monitoring signal is set by a control (12) having two modes of operation; in the first mode of operation, the control controls the generator to transmit an analog monitoring signal by maintaining the frequency of the square wave signal (CK) at a constant value throughout the duration of the monitored radio link, and in the second mode of operation, the control controls the generator (1, 2, 3) to transmit a digital monitoring signal by varying the frequency during the monitored radio link in response to changes in the logical state of the monitoring signal between a first frequency corresponding to the first logical state and a second frequency corresponding to the second logical state. |
