LG -A230 Service Manual page 36

3. TECHNICAL BRIEF
3.5.2 FUNCTIONAL DESCRIPTION
Receiver
The X-GOLD™215 dual-band receiver is based on a Direct Conversion Receiver (DCR) architecture. Input
impedance of the LNAs is optimized to achieve a matching without (external) high quality inductors. By use of
frequency dividers (by 2/4) the LO frequency is derived from the RF frequency synthesizer.
The receive path is fully differential to suppress the on-chip interferences and reduce DC-offsets. The analog
chain of the receiver contains two LNAs (low/high band), a quadrature mixer followed by an analog baseband
filter and 14-bit continuous-time delta-sigma analog-to-digital converter. The filtered and digitized signal is fed
into the digital signal processing chain, which provides decimation, DC offset removal and programmable gain
control.
Figure. 3.5.2 RECEIVER CHAIN BLOCK DIAGRAM
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