| 摘要 |
The invention concerns a method for producing a mobile telephone system dual band transmitter with one single voltage-controlled oscillator (24), which consists in modulating a reference signal with a modulating signal. The modulated reference signal is introduced as set point input in a loop (1) adjusting a single voltage-controlled oscillator of the transmitter. Downstream of said loop, a halving unit (2) is arranged to perform halving on request (C). When a halving is being carried out, in order to prevent the modulation index to be affected by said halving, the method consists in multiplying the modulating signal by two (8, 39). Thus, said multiplication by two of the modulating signal amplitude results in restoring and increasing the spectral occupancy of said modulating signal in the transposed frequency band. |
