A 1 V RF front -end for both HIPERLAN2 and 802.11a
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Transcript of A 1 V RF front -end for both HIPERLAN2 and 802.11a
A 1 V RF front-end for both HIPERLAN2 and
802.11a
A 1 V RF front-end for both HIPERLAN2 and
802.11a
T. Taris, JB. Begueret, H. Lapuyade, Y. Deval
IXL laboratory, University of Bordeaux 1, 33405 Talence, France
OUTLINEOUTLINE
• HIPERLAN2 and 802.11a requirements
• Wireless mass market design constrains
• LNA
• MIXER
• RF Front-end
• Measurement results
• Conclusions
HIPERLAN2 and 802.11a requirementsHIPERLAN2 and 802.11a requirements
LNA VGA
PBF PBF
Mixer
LO
Communication standard
HiperLAN2 and 802.11a
gain 10 dB
Noise Figure 10 dB
ICP1 -21 dBm
IIP3 -10 dBm
Frequency band 5.15-5.35 GHz
Wireless mass market constrainsWireless mass market constrains
Wireless applications + Mass market
CMOS VLSI
analog design
Low Power / Low Voltage
Power aware systems
<10 mW / ~1V
LNALNA
Gain
Input matching Low noise figure
Ftot = FLNA+(Fmixer-1)/GLNA
Maximum signal collected
Ftot = FLNA+(Fmixer-1)/GLNA
Low power
&
Low voltage
LNALNA
RF
bias
out
MLNA
Lg
Ls
Inductive Degeneration
Tuned Load
50 input matchingLow Noise Figure
)²1.(...5
21 cF
T
sgs
m LC
gZin .
Good Linearity
Reduce Miller Effect
MixerMixer
Gain
Linearity
Mixing
operation Low power
&
Low voltageVoltage dynamic range trade-off
Mixing principle brought into play
Principle efficiency
MixerMixer
VLO
VFI
VRF
Low-pass filter
behavior
High-pass filter
behavior bias
)²(2
..TGS
oxnD VV
LWCµ
I )cos()cos( tVtVVV RFRFLOLObiasGS
tVVL
WCµi LORFLORF
oxnD )cos(...
2
..
In saturation region: Assuming:
RF Front-EndRF Front-End
LNA Mixer
Mmix
MLNA
Rconv
Cd1
Cd2
RF
LO
FI
R R
Measurement resultsMeasurement results
• Inductive degeneration matching
S11 = -26 dB Isolation LO>RF = -34 dB
• Due to closeness of RF and LO port
Measurement resultsMeasurement results
0.8 0.9 1 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8Supply Voltage (V)
1
2
3
4
5
6
7
8
9
10
Gain (dB)
Gain = 10 dB @ 1 V ICP1=-9 dBm & IIP3=0 dBm
• Good input matching
• Architecture well suited to low voltage
• Efficiency of resistor load
• Bypass filter behavior
-20-25 -15 -10 Pin(dBm)
-15
-10
-5
0
Pout(dBm)
0
ICP1
IIP3
-20-25 -15 -10 Pin(dBm)
-15
-10
-5
0
Pout(dBm)
0
ICP1
IIP3
Measurement resultsMeasurement results
Measurment results
Requirements
Frequency band
5.15-5.35 GHz 5.15-5.35 GHz
Supply 1 V NC
Gain 10 dB 10 dB
Noise Figure 8 dB 10 dB
Current consumption
6 mA NC
ICP1 -9 dBm -21 dBm
IIP3 0 dBm -10 dBm
Isolation LO>RF
-34 dBm > -30 dBm
ConclusionsConclusions
Fulfill successfully both HIPERLAN2 and
802.11a requirements
Operating under 1V and consuming only 6
mA, it is well suited to low power/low voltage
applications
implemented in CMOS VLSI technologie its
weak bulkiness (750µm500µm ) dedicates it to
System On a Chip (SOC) applications
PerspectivesPerspectives
Improve isolation between LO and RF port
Architecture without inductance (matching
trade-off)
Enhance the conversion gain (linearity trade-
off)