Method and apparatus for auto gain control in radio receiver
View Patent ↗The present invention relates to the field of communication technologies and discloses a method and an apparatus for auto gain control (AGC) in a radio receiver, which can ensure that a radio frequency device, an analog device, and various nodes in a digital domain are non-saturated and that useful signal power is adjusted to a certain power level. According to the present invention, total signal power on an air interface is subtracted from a preset first target power to obtain an analog auto gain control (AAGC) gain, and then a second target power is subtracted from an interference signal power in a digital baseband to obtain a digital auto gain control (DAGC) gain.
1. A method for auto gain control (AGC) in a radio receiver, comprising:
subtracting a total signal power on an air interface from a preset first target power to obtain an analog auto gain control (AAGC) gain;
subtracting a second target power from an interference signal power in a digital baseband to obtain a digital auto gain control (DAGC) gain;
performing analog processing and analog-to-digital conversion on an analog signal of the radio receiver to obtain a digital signal, wherein in the analog processing, the AAGC gain is used to perform gain control over the analog signal; and
performing digital processing on the digital signal to obtain a processing result, wherein in the digital processing, the DAGC gain is used to perform gain control over the digital signal.
2. The AGC method in the radio receiver according to claim 1 , further comprising adding an interference signal power on the air interface to a non-interference signal power on the air interface to obtain the total signal power on the air interface.
3. The AGC method according to claim 2 , further comprising:
determining the interference signal power on the air interface according to
W
=
A
-
10
log
10
(
1
-
10
Y
10
)
+
X
;
and
determining the non-interference signal power on the air interface according to
P
=
B
-
(
A
-
10
log
10
(
1
-
10
Y
10
)
)
,
wherein W is the interference signal power on the air interface,
wherein P is the non-interference signal power on the air interface,
wherein A is the interference signal power in the digital baseband,
wherein B is signal power of a current wideband RSSI,
wherein X is a capability of a radio frequency filter to suppress preset interference, and
wherein Y is a capability of a baseband filter to suppress the preset interference.
4. The AGC method in the radio receiver according to claim 1 , wherein the second target power is obtained by subtracting Tb from Ta, wherein Ta is a target power for a wideband RSSI, and Tb is a target power for a narrowband RSSI.
5. The AGC method in the radio receiver according to claim 1 , wherein the interference signal power in the digital baseband is obtained by subtracting a signal power of a current narrowband RSSI from a signal power of a current wideband RSSI.
6. An apparatus for auto gain control (AGC) in a radio receiver, comprising:
a processor configured to:
subtract total signal power on an air interface from preset first target power to obtain an analog auto gain control (AAGC) gain; and
subtract second target power from interference signal power in a digital baseband to obtain a digital auto gain control (DAGC) gain;
an analog signal processing unit configured to perform analog processing and analog-to-digital conversion on an analog signal of the radio receiver to obtain a digital signal, wherein in the analog processing, the AAGC gain is used to perform gain control over the analog signal; and
a digital signal processing unit coupled to the analog signal processing unit,
wherein the digital signal processing unit is configured to perform digital processing on the digital signal to obtain a processing result, and
wherein in the digital processing, the DAGC gain is used to perform gain control over the digital signal.
7. The apparatus according to claim 6 , further comprising a first calculating unit configured to add an interference signal power on the air interface to a non-interference signal power on the air interface to obtain the total signal power on the air interface.
8. The apparatus according to claim 7 , wherein the first calculating unit is further configured to:
determine the interference signal power on the air interface according to
W
=
A
-
10
log
10
(
1
-
10
Y
10
)
+
X
;
and
determine the non-interference signal power on the air interface according to
P
=
B
-
(
A
-
10
log
10
(
1
-
10
Y
10
)
)
,
wherein W is the interference signal power on the air interface,
wherein P is the non-interference signal power on the air interface,
wherein A is the interference signal power in the digital baseband,
wherein B is signal power of a current wideband RSSI (WB-RSSI),
wherein X is a capability of a radio frequency filter to suppress preset interference, and
wherein Y is a capability of a baseband filter to suppress the preset interference.
9. The apparatus according to claim 6 , further comprising a second calculating unit configured to obtain the second target power by subtracting Tb from Ta, wherein Ta is a target power of a WB-RSSI, and Tb is a target power of a narrowband RSSI.
10. The apparatus according to claim 6 , further comprising a third calculating unit, configured to subtract a signal power of a current narrowband RSSI from a signal power of the current wideband RSSI to obtain the interference signal power in the digital baseband.