| 摘要 |
<p>A self-tuning circuit for quadrature signal amplitude matching in a low intermediate frequency receiver comprising
- a poly-phase filter (40) for filtering a received signal (300) and generating two filtered signals (402, 404) being in quadrature
- a frequency down-conversion mixer (50) for shifting the two filtered signals (402, 404) to a low intermediate frequency (IF) and generating an in-phase (520) and a quadrature (540) down-converted signal
- an amplifying stage (60) comprising an in-phase amplifier (64) for amplifying the in-phase down-converted signal (540) and a quadrature amplifier (62) for amplifying the quadrature down-converted signal (520) characterised in that
the poly-phase filter (40) is a single-stage poly-phase filter comprising integrated passive components (R, C), wherein the values of these integrated passive components (R, C) deviate from the corresponding design values (Ro, Co) by the deviation factors (k r , k c ) due to the manufacturing process of the self-tuning circuit,
the in-phase amplifier (64) has a first transconductance (gm i ) and the quadrature amplifier has a second transconductance (gm q ) different from the first transconductance (gm i ), the first and second transconductances depending on the deviation factors (k r , k c ) so as to obtain amplitude matching between the output signals (640, 620) of the in-phase amplifier (64) and the quadrature amplifier (62), despite said deviation factors (k r , k c ).</p> |
