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RF65
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ADVANCED COMMUNICATIONS & SENSING
DATASHEET
The following figure illustrates the AGC behavior:
:
Towards
-125 dBm
16dB
7dB
11dB
9dB
11dB
Pin [dBm]
G1
G2
G3
G4
G5
G6
Higher Sensitivity
Lower Linearity
Lower Noise Figure
Lower Sensitivity
Higher Linearity
Higher Noise Figure
Figure 6. AGC Thresholds Settings
The following table summarizes the performance (typical figures) of the complete receiver:
Table 9
Receiver Performance Summary
Input Power
Pin
Gain
Setting
Receiver Performance (typ)
P
-1dB
[dBm]
NF
[dB]
IIP3
[dBm]
IIP2
[dBm]
Pin < AgcThresh1
G1
-37
7
-18
+35
AgcThresh1 < Pin < AgcThresh2
G2
-31
13
-15
+40
AgcThresh2 < Pin < AgcThresh3
G3
-26
18
-8
+48
AgcThresh3 < Pin < AgcThresh4
G4
-14
27
-1
+62
AgcThresh4 < Pin < AgcThresh5
G5
>-6
36
+13
+68
AgcThresh5 < Pin
G6
>0
44
+20
+75
3.4.3.1. RssiThreshold Setting
For correct operation of the AGC,
RssiThreshold
in
RegRssiThresh
must be set to the sensitivity of the receiver. The
receiver will remain in WAIT mode until
RssiThreshold
is exceeded.
Note
When AFC is enabled and performed automatically at the receiver startup, the channel filter used by the receiver
during the AFC and the AGC is RxBwAfc instead of the standard RxBw setting. This may impact the sensitivity of
the receiver, and the setting of RssiThreshold accordingly
3.4.3.2. AGC Reference
The AGC reference level is automatically computed in the RF65, according to:
AGC Reference [dBm] = -174 + NF + De10.log(2*
RxBw
) + FadingMargin [dBm]