| 摘要 |
The method includes the use of two base signals (S0, S90), mutually in quadrature and susceptible to the quadrature error, to obtain two pairs of retarded signals, (SR0, SR180) and SR90, SR270), where the signals in each pair are mutually in opposition. The value of each delay is continually adjusted on the basis of two differential signals (SIS1, SIS2) obtained by direct or indirect crossed mixing of two pairs of retarded signals in order to obtain four retarded signals almost in quadrature independently of the quadrature error. The method also includes a low-pass filtering by filters (FA, FB) and a summation of two pairs of differential signals to obtain one pair of differential signals (SDFS1, SDFS2), and a continual adjustment of the value of first delay on the basis of one differential signals while adjusting the value of second delay on the basis of other differential signal so to increase the value of one delay and decrease the value of other delay in order to obtain the four retarded signals almost in quadrature. The method also includes a form modification of signals before mixing by circuits (MFA, MFB), and an integration by a filter-integrator (FI) of two differential signals after filtering and summation. The device comprises a local oscillator (LO) as the base signals generator, and a differential In-phase/Quadrature Phase-Locked Loop (IQPLL) comprising two delay lines (DLA, DLB) and means for differential adjustment including form-modifying circuits (MFA, MFB), passive mixers (MPA, MPB), low-pass filters (FA, FB), an active filter-integrator (FI) in common control mode, and an insulation block (BI) for insulating the filter-integrator from the noise generated by the delay lines. Each delay line (DLA, DLB) contains a differential comparator with variable load. Each passive mixer (MPA, MPB) contains four transistors connected in a ring. The device is integrated on silicon. A receiver for digital television signals via satellite comprises a tuner which incorporates the proposed device.
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