摘要 |
PCT No. PCT/FI92/00148 Sec. 371 Date Nov. 5, 1993 Sec. 102(e) Date Dec. 17, 1993 PCT Filed May 8, 1992 PCT Pub. No. WO92/20149 PCT Pub. Date Nov. 12, 1992.A frequency adjustment method for an RF bandpass filter, especially a combiner filter, wherein the center frequency of the passband of the RF bandpass filter is adjusted in response to the RF power reflected from the input of the bandpass filter or passed through the bandpass filter. A sample signal proportional to the RF power reflected from the input of the bandpass filter or passed through the bandpass filter is mixed with a signal of substantially the transmitting frequency. The mixing result is lowpass-filtered and the bandpass filter is adjusted in response to the lowpass-filtered mixing result. |