Circuit Note
CN-0150
Devices Connected/Referenced
Circuits from the Lab™ reference circuits are engineered and
tested for quick and easy system integration to help solve today’s
analog, mixed-signal, and RF design challenges. For more
information and/or support, visit www.analog.com/CN0150.
AD8318
1 MHz to 8 GHz, 70 dB, Logarithmic
Detector/Controller
AD7887
2.7 V to 5.25 V, Micropower, 2-Channel,
125 kSPS, 12-Bit ADC in 8-Lead MSOP
ADR421
Precision, Low Noise, 2.5 V Reference
Software-Calibrated, 1 MHz to 8 GHz, 60 dB RF Power
Measurement System Using a Logarithmic Detector
A simple two-point system calibration is performed in the
digital domain.
EVALUATION AND DESIGN SUPPORT
Circuit Evaluation Boards
CN-0150 Circuit Evaluation Board (EVAL-CN0150A-SDPZ)
System Demonstration Platform (EVAL-SDP-CB1Z)
Design and Integration Files
Schematics, Layout Files, Bill of Materials
The AD8318 maintains accurate log conformance for signals of
1 MHz to 6 GHz and provides useful operation to 8 GHz.
The device provides a typical output voltage temperature
stability of ±0.5 dB.
CIRCUIT FUNCTION AND BENEFITS
This circuit measures RF power at any frequency from
1 MHz to 8 GHz over a range of approximately 60 dB. The
measurement result is provided as a digital code at the output of
a 12-bit ADC with serial interface and integrated reference. The
output of the RF detector has a glueless interface to the ADC and
uses most of the ADC’s input range without further adjustment.
The AD7887 ADC can be configured for either dual or single
channel operation via the on-chip control register. There is a
default single-channel mode that allows the AD7887 to be operated
as a read-only ADC, thereby simplifying the control logic.
Typical data is shown for the two devices operating over a
−40°C to +85°C temperature range.
+5V
VPOS
R4
499Ω
12
11
C5
0.1µF
10
9
10µF
0.1µF
C6
100pF
13 TEMP
PULSED RF
INPUT
C1 1nF
RFIN
R1
52.3Ω
C2 1nF
CMOP 8
14 INHI
15 INLO
16 ENBL
1
SEE
TEXT
VOUT 6
0.1µF
CLPF 5
CMIP CMIP
2
VPSI
VPSI
3
4
AD7887
VOUT
VSET 7
AD8318
SERIAL
INTERFACE
VDD
CMIP CMIP TADJ VPSO
C9
0.1µF
AIN0
SCLK
AIN1/
VREF
DOUT
GND
µC/µP
DIN
CS
C7
100pF
C8
0.1µF
08967-001
VPOS
Figure 1. Software-Calibrated RF Measurement System (Simplified Schematic: All Connections Not Shown)
Rev. C
Circuits from the Lab™ circuits from Analog Devices have been designed and built by Analog Devices
engineers. Standard engineering practices have been employed in the design and construction of
each circuit, and their function and performance have been tested and verified in a lab environment at
room temperature. However, you are solely responsible for testing the circuit and determining its
suitability and applicability for your use and application. Accordingly, in no event shall Analog Devices
be liable for direct, indirect, special, incidental, consequential or punitive damages due to any cause
whatsoever connected to the use of any Circuits from the Lab circuits. (Continued on last page)
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©2010–2012 Analog Devices, Inc. All rights reserved.
CN-0150
Circuit Note
CIRCUIT DESCRIPTION
The RF signal being measured is applied to the AD8318. The
device is configured in its so-called measurement mode, with
the VSET and VOUT pins connected together. In this mode,
the output voltage vs. the input signal level is linear-in-dB
(nominally −24 mV/dB) and has a typical output voltage range
of 0.5 V to 2.1 V.
The AD8318 output is connected directly to the AD7887, 12-bit
ADC. The ADC uses its internal reference and is configured for
a 0 V to 2.5 V input, resulting in an LSB size of 610 μV. With the RF
detector providing a nominal −24 mV/dB, the digital resolution
is 39.3 LSBs/dB. With this much resolution, there is little value
in trying to scale the 0.5 V to 2.1 V signal from the RF detector
to exactly fit the 0 V to 2.5 V range of the ADC.
The transfer function of the detector can be approximated by
the equation
Using the two known input power levels, PIN_1 and PIN_2,
and the corresponding observed ADC codes, CODE_1 and
CODE_2, SLOPE_ADC, and INTERCEPT can be calculated
using the following equations:
SLOPE_ADC = (CODE_2 − CODE_1)/(PIN_2 − PIN_1)
INTERCEPT = PIN_2 − (CODE_2/SLOPE_ADC)
Once SLOPE_ADC and INTERCEPT are calculated and stored (in
nonvolatile RAM) during factory calibration, they can be used
to calculate an unknown input power level, PIN, when the
equipment is in operation in the field using the equation
PIN = (CODE_OUT/SLOPE_ADC) + INTERCEPT
Figure 3 through Figure 8 show how the system transfer function
deviates from this straight line equation, particularly at the
endpoints of the transfer function. This deviation is expressed
in dB using the equation
Error (dB) = Measured Input Power − True Input Power =
(CODE_OUT/SLOPE_ADC) + INTERCEPT – PIN_TRUE
VOUT = SLOPE × (PIN − INTERCEPT)
where SLOPE is in mV/dB (−24 mV/dB nominal); INTERCEPT is
the x-axis intercept with a unit of dBm (20 dBm nominal);
and PIN is the input power expressed in dBm. A typical plot
of detector output voltage vs. input power is shown in Figure 2.
1.5
1.5
0.5
1.2
0
–0.5
0.9
0.6
0.3
RANGE OF
CALCULATION
OF SLOPE AND
INTERCEPT
0
–65 –60 –55 –50 –45 –40 –35 –30 –25 –20 –15 –10 –5
PIN (dBm)
–1.0
–1.5
0
5
10 15
INTERCEPT
Figure 2. Typical Output Voltage vs. Input Signal Level for the AD8318
The plots shown in Figure 3 through Figure 8 show the typical
system performance that can be obtained using the AD8318 and
AD7887BR in an RF power measurement system. The graphs
depict the RF input power in dBm vs. the ADC output code and
output error in dB (scaled on the axes on the right side of the
plots). They were generated from data taken with various input
power levels, frequencies, and temperatures and with both internal
and external ADC voltage references. The charts show improved
system performance and lower temperature drift with the use of
a low drift external ADC voltage reference. (See the Common
Variations section for more details about the use of an external
reference.
A complete design support package for this circuit note can be
found at www.analog.com/CN0150-DesignSupport.
At the output of the ADC, the equation can be written as
CODE_OUT = SLOPE_ADC × (PIN − INTERCEPT)
4
4.0k
Because the slope and intercept of the system vary from device
to device, a system level calibration is required. A calibration is
performed by applying two known signal levels close to the
endpoints of the AD8318 linear input range and measuring the
corresponding output codes from the ADC. The calibration
points chosen should be well within the linear operating
range of the device (−10 dBm and −50 dBm in this case).
3.5k
3.0k
CODE_2
ADC CODE
where SLOPE_ADC is in codes/dB and PIN and INTERCEPT
are in dBm. Figure 3 shows a typical detector power sweep in
terms of input power and observed ADC codes.
+25°C CODE
–40°C CODE
+85°C CODE
+25°C ERROR
–40°C ERROR
+85°C ERROR
3
2
2.5k
1
2.0k
0
1.5k
–1
1.0k
–2
0.5k
–3
CODE_1
0
–70
OUTPUT ERROR (dBm)
1.0
–4
–60 –50
–40
–30
–20 –10
0
10
INPUT POWER (dBm)
PIN_2
PIN_1
Figure 3. Input = 900 MHz, ADC Using an Internal 2.5 V Reference
Rev. C | Page 2 of 5
08967-003
1.8
08967-002
VOUT (V)
2.1
2.0
VOUT 25°C
ERROR 25°C
ERROR (dB)
2.4
where:
CODE_OUT is the ADC output code.
SLOPE_ADC is the stored ADC slope in codes/dB.
INTERCEPT is the stored intercept.
PIN_TRUE is the exact (and unknown) input level.
Circuit Note
CN-0150
2
3.0k
2.0k
0
1.5k
–1
1.0k
–2
0.5k
–3
0
–70
–60
–50
–40
–30
–20
–10
0
10
–4
INPUT POWER (dBm)
–1
1.0k
–2
0.5k
–3
–20
–10
0
10
–4
ADC CODE
1.5k
–30
INPUT POWER (dBm)
ADC CODE
3.0k
2
0
1.5k
–1
1.0k
–2
0.5k
–3
–40
–30
–20
–10
0
10
–30
–20
–10
0
10
–4
4
+25°C CODE
–40°C CODE
+85°C CODE
+25°C ERROR
–40°C ERROR
+85°C ERROR
3
2
2.5k
1
2.0k
0
1.5k
–1
1.0k
–2
0.5k
–3
–60
–50
–40
–30
–20
–10
0
10
–4
INPUT POWER (dBm)
The AD7887 is a 2-channel, 12-bit ADC with an SPI interface.
The second input channel of this device can be connected to the
AD8318 TEMP pin. This provides a convenient measure of the
ambient temperature around the AD8318. Like the AD8318
power measurement output, the TEMP voltage output should
also be calibrated.
2.0k
–50
–40
COMMON VARIATIONS
1
–60
–50
3
2.5k
0
–70
–60
4
–4
INPUT POWER (dBm)
Figure 6. Input = 1.9 GHz, ADC Using an External 2.5 V Reference
OUTPUT ERROR (dBm)
3.5k
–3
Figure 8. Input = 2.2 GHz, ADC Using an External 2.5 V Reference
08967-006
+25°C CODE
–40°C CODE
+85°C CODE
+25°C ERROR
–40°C ERROR
+85°C ERROR
0.5k
0
–70
Figure 5. Input = 1.9 GHz, ADC Using an Internal 2.5 V Reference
4.0k
–2
3.0k
0
–40
1.0k
2
2.0k
–50
–1
3.5k
1
–60
1.5k
3
2.5k
0
–70
0
Figure 7. Input = 2.2 GHz, ADC Using an Internal 2.5 V Reference
OUTPUT ERROR (dBm)
ADC CODE
3.0k
2.0k
4.0k
08967-005
3.5k
1
INPUT POWER (dBm)
4
+25°C CODE
–40°C CODE
+85°C CODE
+25°C ERROR
–40°C ERROR
+85°C ERROR
2.5k
0
–70
Figure 4. Input = 900 MHz, ADC Using an External 2.5 V Reference
4.0k
2
OUTPUT ERROR (dBm)
1
3
08967-008
2.5k
+25°C CODE
–40°C CODE
+85°C CODE
+25°C ERROR
–40°C ERROR
+85°C ERROR
OUTPUT ERROR (dBm)
3.5k
ADC CODE
ADC CODE
3.0k
3
OUTPUT ERROR (dBm)
3.5k
4
4.0k
08967-004
+25°C CODE
–40°C CODE
+85°C CODE
+25°C ERROR
–40°C ERROR
+85°C ERROR
08967-007
4
4.0k
If the end application requires only a single channel, the 12-bit
AD7495 can be used. In multichannel applications that require
multiple ADCs and DAC channels, the AD7294 can be used.
In addition to providing four 12-bit DAC outputs, this subsystem
chip includes four uncommitted ADC channels, two high-side
current sense inputs, and three temperature sensors. Current
and temperature measurements are digitally converted and
available to read over the I2C-compatible interface.
The temperature stability of the circuit can be improved using an
external ADC reference. The AD7887 internal 2.5 V reference has
a 50 ppm/°C drift, which is approximately 15 mV over a 125°C
range. Because the detector has a slope of −24 mV/dB, the ADC
reference drift contributes approximately ±0.3 dB to the temperature
drift error budget. The AD8318 temperature drift is approximately
±0.5 dB over a similar temperature range. (This varies with
frequency. See the AD8318 data sheet for more details.)
Rev. C | Page 3 of 5
CN-0150
Circuit Note
If an external voltage reference is to be used, the ADR421 2.5 V
reference is recommended. Its 1 ppm/°C temperature drift results
in a reference voltage variation of only 312 μV from −40°C to
+85°C. This has a negligible effect on the overall temperature
stability of the system.
6 V wall wart can be connected to the barrel connector on the
board and used in place of the 6 V power supply. Connect the USB
cable supplied with the SDP board to the USB port on the PC.
Note: Do not connect the USB cable to the mini USB connector
on the SDP board at this time.
If a less dynamic range is required, the AD8317 (55 dB) or AD8319
(45 dB) log detector can be used. If a true rms responding power
measurement is required, the AD8363 (50 dB) or ADL5902
(65 dB) can be used.
Test
CIRCUIT EVALUATION AND TEST
Apply power to the 6 V supply (or wall wart) connected to
EVAL-CN0150A-SDPZ circuit board. Launch the evaluation
software and connect the USB cable from the PC to the USB
mini connector on the SDP board.
This circuit uses the EVAL-CN0150A-SDPZ circuit board and
the EVAL-SDP-CB1Z System Demonstration Platform (SDP)
evaluation board. The two boards have 120-pin mating connectors,
allowing for the quick setup and evaluation of the circuit’s
performance. The EVAL-CN0150A-SDPZ board contains the
circuit to be evaluated, as described in this note, and the SDP
evaluation board is used with the CN0150A evaluation software to
capture the data from the EVAL-CN0150A-SDPZ circuit board.
Once USB communications are established, the SDP board can
now be used to send, receive, and capture serial data from the
EVAL-CN0150A-SDPZ board.
Equipment Needed
Temperature testing was performed using a Test Equity Model 107
environmental chamber. The EVAL-CN0150A-SDPZ evaluation
board was placed in the chamber via a slot in the test chamber
door, with the SDP evaluation board extending outside.
• PC with a USB port and Windows® XP or Windows Vista®
(32-bit), or Windows 7 (32-bit)
• EVAL-CN0150A-SDPZ Circuit Evaluation Board
The data in this circuit note were generated using a Rohde &
Schwarz SMT-03 RF signal source and an Agilent E3631A power
supply. The signal source was set to the frequencies indicated in
the graphs, and the input power was stepped and data recorded
in 1 dB increments.
Information and details regarding how to use the evaluation
software for data capture can be found in the CN0150A
evaluation software readme file.
• EVAL-SDP-CB1Z SDP Evaluation Board
• CN0150A Evaluation Software
• Power supply: 6 V or 6 V wall wart
Information regarding the SDP board can be found in the SDP
User Guide.
• Environmental chamber
• RF signal source
LEARN MORE
• Coaxial RF cable with SMA connectors
CN0150 Design Support Package:
http://www.analog.com/CN0150-DesignSupport
Getting Started
SDP User Guide
Load the evaluation software by placing the CN0150A evaluation
software CD in the CD drive of the PC. Using My Computer,
locate the drive that contains the evaluation software CD and
open the readme file. Follow the instructions contained in the
readme file for installing and using the evaluation software.
MT-031 Tutorial, Grounding Data Converters and Solving the
Mystery of “AGND” and “DGND,” Analog Devices.
MT-077 Tutorial, Log Amp Basics, Analog Devices.
MT-078 Tutorial, High Speed Log Amps, Analog Devices.
Functional Block Diagram
MT-101 Tutorial, Decoupling Techniques, Analog Devices.
See Figure 1 of this circuit note for the circuit block diagram
and the EVAL-CN150A-SDPZ-SCH-Rev0.pdf file for the
circuit schematics. This file is contained in the CN0150
Design Support Package.
Whitlow, Dana. Design and Operation of Automatic Gain
Control Loops for Receivers in Modern Communications
Systems. Chapter 8. Analog Devices Wireless Seminar. 2006.
Setup
Connect the 120-pin connector on the EVAL-CN0150A-SDPZ
circuit board to the CON A connector on the EVAL-SDP-CB1Z
evaluation (SDP) board. Use nylon hardware to firmly secure
the two boards, using the holes provided at the ends of the 120-pin
connectors. Using an appropriate RF cable, connect the RF signal
source to the EVAL-CN0150A-SDPZ board via the SMA RF
input connector. With power to the supply off, connect a 6 V power
supply to the +6V and GND pins on the board. If available, a
Data Sheets and Evaluation Boards
CN-0150 Circuit Evaluation Board (EVAL-CN0150A-SDPZ)
System Demonstration Platform (EVAL-SDP-CB1Z)
AD7887 Data Sheet
AD7887 Evaluation Board
AD8318 Data Sheet
AD8318 Evaluation Board
ADR421 Data Sheet
Rev. C | Page 4 of 5
Circuit Note
CN-0150
REVISION HISTORY
2/12—Rev. B to Rev. C
Changed 70 dB to 60 dB in Circuit Note Title ..............................1
3/11—Rev. A to Rev. B
Added Evaluation and Design Support Section............................1
Added Circuit Evaluation and Test Section...................................4
8/10— Rev. 0 to Rev. A
Changes to the Circuit Function and Benefits Section ................1
Changes to the Circuit Description Section ..................................2
Changes to the Common Variations Section ................................4
4/10—Revision 0: Initial Version
I2C refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors).
(Continued from first page) Circuits from the Lab circuits are intended only for use with Analog Devices products and are the intellectual property of Analog Devices or its licensors. While you
may use the Circuits from the Lab circuits in the design of your product, no other license is granted by implication or otherwise under any patents or other intellectual property by
application or use of the Circuits from the Lab circuits. Information furnished by Analog Devices is believed to be accurate and reliable. However, Circuits from the Lab circuits are supplied
"as is" and without warranties of any kind, express, implied, or statutory including, but not limited to, any implied warranty of merchantability, noninfringement or fitness for a particular
purpose and no responsibility is assumed by Analog Devices for their use, nor for any infringements of patents or other rights of third parties that may result from their use. Analog Devices
reserves the right to change any Circuits from the Lab circuits at any time without notice but is under no obligation to do so.
©2010–2012 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
CN08967-0-2/12(C)
Rev. C | Page 5 of 5
Circuit Note
CN-0178
Circuits from the Lab™ reference circuits are engineered and
tested for quick and easy system integration to help solve today’s
analog, mixed-signal, and RF design challenges. For more
information and/or support, visit www.analog.com/CN0178.
Devices Connected/Referenced
ADL5902
50 MHz to 9 GHz, 65 dB TruPwr™ Detector
AD7466
Micropower, 12-Bit, 200 kSPS SAR ADC
Software-Calibrated, 50 MHz to 9 GHz, RF Power Measurement System
EVALUATION AND DESIGN SUPPORT
The measurement result is provided as serial data at the output
of a 12-bit ADC (AD7466). A simple 4-point system calibration
at ambient temperature is performed in the digital domain.
Circuit Evaluation Boards
CN-0178 Circuit Evaluation Board (EVAL-CN0178-SDPZ)
System Demonstration Platform (EVAL-SDP-CB1Z)
Design and Integration Files
Schematics, Layout Files, Bill of Materials
The interface between the RF detector and the ADC is
straightforward, consisting of two signal scaling resistors and
no active components. In addition, the ADL5902 internal 2.3 V
reference voltage provides the supply and reference voltage for
the micropower ADC. The AD7466 has no pipeline delay and
is operated as a read-only SAR ADC.
CIRCUIT FUNCTION AND BENEFITS
This circuit uses the ADL5902 TruPwr™ detector to measure the
rms signal strength of RF signals with varying crest factors
(peak-to-average ratio) over a dynamic range of approximately
65 dB and operates at frequencies from 50 MHz up to 9 GHz.
+5V
+5V
C3
0.1µF
C7
0.1µF
C4
100pF
C5
100pF
VPOS
VPOS
3
10
TEMPERATURE
SENSOR
ADL5902
RFIN
R3
60.4Ω
C10
100pF
The overall circuit achieves temperature stability of
approximately ±0.5 dB.
C9A
0.1µF
8
TEMP
C10A
10µF
VDD
1
INHI
INLO
14
X2
C12
100pF
NC
IDET
VIN
R10
3
1.21kΩ
15
LINEAR-IN-dB VGA
(NEGATIVE SLOPE)
7
X2
VSET
G=5
6
R11
2kΩ
VOUT
BIAS AND POWERDOWN CONTROL
5
11
1
R9
1430Ω
12
9
VTGT
R10
3.74kΩ
CS
DGND
C9
0.1µF
AD7466
2
4
COMM
DATA
CS
GND
COMM
R11
2kΩ
09331-001
R12
301Ω
VREF
CLK
SDATA
5
6
CLPF
26pF
SCLK
4
CONTROL
LOGIC
VREF
2.3V
NC 13
TADJ
12-BIT
SUCCESSIVE
APPROXIMATION
ADC
ITGT
2
NC 16
T/H
Figure 1. Software-Calibrated RF Power Measurement System
Rev.A
Circuits from the Lab™ circuits from Analog Devices have been designed and built by Analog Devices
engineers. Standard engineering practices have been employed in the design and construction of
each circuit, and their function and performance have been tested and verified in a lab environment at
room temperature. However, you are solely responsible for testing the circuit and determining its
suitability and applicability for your use and application. Accordingly, in no event shall Analog Devices
be liable for direct, indirect, special, incidental, consequential or punitive damages due to any cause
whatsoever connected to the use of any Circuits from the Lab circuits. (Continued on last page)
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©2010–2011 Analog Devices, Inc. All rights reserved.
CN-0178
Circuit Note
Data is shown for the two devices operating over a −40°C to
+85°C temperature range.
The transfer function of the detector can be approximated by
the equation
VOUT = SLOPE_DETECTOR × (PIN − INTERCEPT)
CIRCUIT DESCRIPTION
CODE = SLOPE × (PIN − INTERCEPT)
where SLOPE is the combined slope of the detector, the scaling
resistors, and the ADC, and has the unit of counts/dB; PIN and
INTERCEPT still have the unit of dBm.
Figure 3 shows a typical detector power sweep in terms of input
power and observed ADC output codes for a 700 MHz input
signal.
4096
6
+85°C CODE
–40°C CODE
+25°C CODE
+25°C ERROR 4-POINT CAL @ 0dBm,
–20dBm, –45dBm, AND, –58dBm
+85°C ERROR 4-POINT CAL
–40°C ERROR 4-POINT CAL
3755
3413
3072
5
4
3
2731
2
2389
1
2048
0
1707
–1
1365
–2
1024
–3
683
–4
341
–5
A typical plot of detector output voltage vs. input power is
shown in Figure 2 (without output scaling).
0
–70
–6
–60
–50
–40
–30
PIN (dBm)
–20
–10
0
10
ERROR (dB)
The ADC full-scale voltage is equal to 2.3 V. The maximum
detector output voltage (when operating in its linear input
range) is approximately 3.5 V (see ADL5902 data sheet figures
6, 7, 8, 12, 13, and 14) and must, therefore, be scaled down by a
factor of 0.657 before driving the AD7466. This scaling is
implemented using a simple resistor divider R10 and R11
(1.21 kΩ and 2.0 kΩ). These values provide an actual scaling
factor of 0.623, which ensures that the ADL5902 RF detector
does not overdrive the ADC by building in some room for
resistor tolerance.
At the output of the ADC, VOUT is replaced by the ADC’s
output code, and the equation can be rewritten as
09331-003
The power supply voltage and reference voltage for the AD7466
12-bit ADC are provided by the ADL5902 internal 2.3 V
reference. Because the AD7466 consumes so little current
(16 µA when sampling at 10 kSPS), the ADL5902’s reference
voltage output can supply the ADC, as well as the temperature
compensating and rms accuracy-scaling network consisting of
R9, R10, R11, and R12.
where SLOPE_DETECTOR is in mV/dB; INTERCEPT is the
x-axis intercept with a unit of dBm; PIN is the input power
in dBm.
ADC CODE
The RF signal being measured is applied to the input of the
ADL5902, a linear-in-dB rms-responding rms detector. The
external 60.4 Ω resistor, R3, combined with the relatively high
input impedance of the ADL5902 ensures a broadband 50 Ω
match to the RF input. The ADL5902 is configured in its
so-called “measurement mode,” with the VSET and VOUT
pins connected together. In this mode the output voltage is
proportional to the logarithm of the rms value of the input. In
other words, the reading is presented directly in decibels and is
scaled to 1.06 V per decade, or 53 mV/dB.
Figure 3. ADC Output Code and Error vs. RF Input Power @ 700 MHz
4.0
3.5
Overall SLOPE and INTERCEPT will vary from system to
system. This variation is caused by part to part variations in the
transfer function of the RF detector, the scaling resistors, and
the ADC. As a result, a system level calibration is required to
determine the complete system SLOPE and INTERCEPT. In this
application, a 4-point calibration is used to correct for some
nonlinearity in the RF detector’s transfer function, particularly
at the low end. This 4-point calibration scheme yields three
SLOPE and three INTERCEPT calibration coefficients, which
should be stored in nonvolatile RAM (NVM) after calibration.
3.0
VOUT (V)
2.5
2.0
1.5
1.0
0
–70
–60
–50
INTERCEPT
–40
–30
PIN (dBm)
–20
–10
0
10
09331-002
0.5
Figure 2. ADL5902 RMS Detector, Output Voltage vs. Input Power @ 900 MHz
Rev. A| Page 2 of 5
Circuit Note
CN-0178
Figure 4 and Figure 5 show the performance of the circuit at
1 GHz and 2.2 GHz, respectively.
4096
6
+85°C CODE
–40°C CODE
+25°C CODE
+25°C ERROR 4-POINT CAL @ 0dBm,
–20dBm, –45dBm, AND, –58dBm
+85°C ERROR 4-POINT CAL
–40°C ERROR 4-POINT CAL
The SLOPE and INTERCEPT calibration coefficients are
calculated using the equations
ADC CODE
3072
INTERCEPT1= CODE_1/(SLOPE_ADC × PIN_1)
This calculation is then repeated using CODE_2/CODE_3
and CODE_3/CODE_4 to calculate SLOPE2/INTERCEPT2
and SLOPE3/INTERCEPT3, respectively. The six calibration
coefficients should then be stored in NVM along with CODE_1,
CODE_2, CODE_3, and CODE_4.
2
2389
1
2048
0
1707
–1
1365
–2
1024
–3
683
–4
341
–5
0
–70
–6
–60
–20
–10
0
10
6
+85°C CODE
–40°C CODE
+25°C CODE
+25°C ERROR 4-POINT CAL @ 0dBm,
–20dBm, –45dBm, AND, –58dBm
+85°C ERROR 4-POINT CAL
–40°C ERROR 4-POINT CAL
ADC CODE
3072
Figure 3 also includes plots of error vs. temperature. In this case
the measured ADC codes at +85°C and −40°C are compared to
the straight line equations at ambient. This is consistent with a
real world system where system calibration is generally only
practical at ambient temperature.
–30
4096
PIN = (CODE/SLOPE) + INTERCEPT
= (CODE/SLOPE) + INTERCEPT – PIN_TRUE
–40
Figure 4. ADC Output Code and Error vs. RF Input Power @ 1 GHz
3413
Error (dB) = Calculated RF Power − True Input Power
–50
PIN (dBm)
3755
Figure 3 also shows the transfer function variation of the circuit
vs. the above straight line equations. This error function is
caused by bending at the edges of the transfer function, small
ripple in the linear operating range, and drift over temperature.
The error is expressed in dB using the equation
3
2731
When the circuit is in operation in the field, these calibration
coefficients are used to calculate an unknown input power level,
PIN, using the equation
In order to retrieve the appropriate SLOPE and INTERCEPT
calibration coefficients during circuit operation, the observed
CODE from the ADC must be compared to CODE_1, CODE_2,
CODE_3, and CODE_4. For example if the CODE from the
ADC is between CODE_1 and CODE_2, then the SLOPE1 and
INTERCEPT1 should be used. This step can also be used to
provide an underrange or overrange warning. For example, if
the CODE from the ADC is greater than CODE_1 or less than
CODE_4, it indicates that the measured power is outside of the
calibration range
4
5
4
3
2731
2
2389
1
2048
0
1707
–1
1365
–2
1024
–3
683
–4
341
–5
0
–70
–6
–60
–50
–40
–30
–20
–10
0
10
PIN (dBm)
ERROR (dB)
SLOPE1 = ( CODE _1 – CODE_2)/(PIN_1 − PIN_2)
5
ERROR (dB)
3413
09331-004
3755
09331-005
The calibration is performed by applying four known signal
levels to the ADL5902 and measuring the corresponding output
codes from the ADC. The calibration points chosen should be
within the linear operating range of the device. In this example,
calibration points at 0 dBm, −20 dBm, −45 dBm, and −58 dBm
were used.
Figure 5. ADC Output Code and Error vs. RF Input Power @ 2.2 GHz
The performance of this or any high speed circuit is highly
dependent on proper PCB layout. This includes, but is not
limited to, power supply bypassing, controlled impedance lines
(where required), component placement, signal routing, and
power and ground planes. (See MT-031 Tutorial, MT-101 Tutorial,
and article, A Practical Guide to High-Speed Printed-CircuitBoard Layout, for more detailed information regarding PCB
layout.)
A complete design support package for this circuit note can be
found at www.analog.com/CN0178-DesignSupport.
Rev. A| Page 3 of 5
CN-0178
Circuit Note
COMMON VARIATIONS
Functional Block Diagram
For applications that require less RF detection range, the
AD8363 rms detector can be used. The AD8363 has a detection
range of 50 dB and operates at frequencies up to 6 GHz. For
non-rms detection applications, the AD8317/AD8318/AD8319
or ADL5513 can be used. These devices offer varying detection
ranges and have varying input frequency ranges up to 10 GHz
(see CN-0150 for more details).
See Figure 1 of this circuit note for the circuit block diagram,
and the file “EVAL-CN0178-SDPZ-SCH-Rev0.pdf ” for the
circuit schematics. This file is contained in the CN0178 Design
Support Package.
The AD7466 is a single channel, 12-bit ADC with SPI interface.
If the end application requires a multichannel ADC, the dual
12-bit AD7887 can be used. In multichannel applications that
require multiple ADC and DAC channels, the AD7294 can be
used. In addition to providing four 12-bit DAC outputs, this
subsystem chip includes four uncommitted ADC channels,
two high-side current sense inputs, and three temperature
sensors. Current and temperature measurements are digitally
converted and available to read over the I2C-compatible
interface.
CIRCUIT EVALUATION AND TEST
This circuit uses the EVAL-CN0178-SDPZ circuit board and
the EVAL-SDP-CB1Z System Demonstration Platform (SDP)
evaluation board. The two boards have 120-pin mating
connectors, allowing for the quick setup and evaluation of the
circuit’s performance. The EVAL-CN0178-SDPZ board contains
the circuit to be evaluated, as described in this note, and the
SDP evaluation board is used with the CN0178 evaluation
software to capture the data from the EVAL-CN0178-SDPZ
circuit board.
Equipment Needed
• PC with a USB port and Windows® XP or Windows Vista®
(32-bit), or Windows® 7 (32-bit)
• EVAL-CN0178-SDPZ Circuit Evaluation Board
Setup
Connect the 120-pin connector on the EVAL-CN0178-SDPZ
circuit board to the connector marked “CON A” on the
EVAL-SDP-CB1Z evaluation (SDP) board. Nylon hardware
should be used to firmly secure the two boards, using the holes
provided at the ends of the 120-pin connectors. Using an
appropriate RF cable, connect the RF signal source to the
EVAL-CN0178-SDPZ board via the SMA RF input connector.
With power to the supply off, connect a +6 V power supply to
the pins marked “+6 V” and “GND” on the board. If available, a
+6 V "wall wart" can be connected to the barrel connector on
the board and used in place of the +6 V power supply. Connect
the USB cable supplied with the SDP board to the USB port on
the PC. Note: Do not connect the USB cable to the mini USB
connector on the SDP board at this time.
Test
Apply power to the +6 V supply (or “wall wart”) connected to
EVAL-CN0178-SDPZ circuit board. Launch the Evaluation
software, and connect the USB cable from the PC to the USB
mini-connector on the SDP board.
Once USB communications are established, the SDP board can
now be used to send, receive, and capture serial data from the
EVAL-CN0178-SDPZ board.
The data in this circuit note were generated using a Rohde &
Schwarz SMT-03 RF signal source, and an Agilent E3631A
power supply. The signal source was set to the frequencies
indicated in the graphs, and the input power was stepped and
data recorded in 1 dB increments.
Temperature testing was performed using a Test Equity Model
107 environmental chamber. The CN0178-SDPZ evaluation
board was placed in the chamber via a slot in the test chamber
door, with the SDP evaluation board extending outside.
• EVAL-SDP-CB1Z SDP Evaluation Board
• CN0178 Evaluation Software
• Power supply: +6 V, or +6 V “wall wart”
Information and details regarding how to use the evaluation
software for data capture can be found in the CN0178
Evaluation Software ReadMe file.
• Environmental chamber
• RF signal source
• Coaxial RF cable with SMA connectors
Information regarding the SDP board can be found in the
SDP User Guide.
Getting Started
Load the evaluation software by placing the CN0178 Evaluation
Software disc in the CD drive of the PC. Using "My Computer,"
locate the drive that contains the evaluation software disc and
open the Readme file. Follow the instructions contained in the
Readme file for installing and using the evaluation software.
Rev. A| Page 4 of 5
Circuit Note
CN-0178
LEARN MORE
Data Sheets and Evaluation Boards
CN0178 Design Support Package:
http://www.analog.com/CN0178-DesignSupport
CN-0178 Circuit Evaluation Board (EVAL-CN0178-SDPZ)
System Demonstration Platform (EVAL-SDP-CB1Z)
SDP User Guide
ADL5902 Data Sheet
Ardizzoni, John. A Practical Guide to High-Speed PrintedCircuit-Board Layout, Analog Dialogue 39-09, September
2005.
ADL5902 Evaluation Board
AD7466 Data Sheet
CN-0150 Circuit Note, Software-Calibrated, 1 MHz to 8 GHz,
70 dB RF Power Measurement System Using the AD8318
Logarithmic Detector , Analog Devices.
AD7466 Evaluation Board
MT-031 Tutorial, Grounding Data Converters and Solving the
Mystery of “AGND” and “DGND”, Analog Devices.
3/11—Rev. 0 to Rev. A
REVISION HISTORY
MT-073 Tutorial, High Speed Variable Gain Amplifiers (VGAs),
Analog Devices.
MT-077 Tutorial, Log Amp Basics, Analog Devices.
Added Evaluation and Design Support Section ............................ 1
Added Circuit Evaluation and Test Section ................................... 4
10/10—Rev. 0: Initial Version
MT-078 Tutorial, High Speed Log Amps, Analog Devices.
MT-081 Tutorial, RMS-to-DC Converters, Analog Devices.
MT-101 Tutorial, Decoupling Techniques, Analog Devices.
Whitlow, Dana. Design and Operation of Automatic Gain
Control Loops for Receivers in Modern Communications
Systems. Chapter 8. Analog Devices Wireless Seminar. 2006.
I2C refers to a communications protocol originally developed by Philips Semiconductors (now NXP Semiconductors).
(Continued from first page) Circuits from the Lab circuits are intended only for use with Analog Devices products and are the intellectual property of Analog Devices or its licensors. While you
may use the Circuits from the Lab circuits in the design of your product, no other license is granted by implication or otherwise under any patents or other intellectual property by
application or use of the Circuits from the Lab circuits. Information furnished by Analog Devices is believed to be accurate and reliable. However, "Circuits from the Lab" are supplied "as is"
and without warranties of any kind, express, implied, or statutory including, but not limited to, any implied warranty of merchantability, noninfringement or fitness for a particular
purpose and no responsibility is assumed by Analog Devices for their use, nor for any infringements of patents or other rights of third parties that may result from their use. Analog Devices
reserves the right to change any Circuits from the Lab circuits at any time without notice but is under no obligation to do so.
©2010–2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
CN09331-0-3/11(A)
Rev. A| Page 5 of 5
1
2
3
4
5
6
7
8
9
+5V_RF
C7
100pF
+5V_RF
C6
100pF
A
+5V_RF
C5
C3
0.1uF
10uF
+3.3V
C4
0.1uF
A
C8 0.1uF
C9
0.1uF
8
CMIP
CMIP
CMIP
CMIP
1
2
11
12
PAD
TADJ
17
10
C10
GND GND 1
VIN VOUT
GND TRIM
6
5
NIC
NIC
3
7
TP
TP
8
1
3
TP5
3
Q3
BSN20
2
DOUT
Q5
BSN20
2
DIN
3
2
SCLK
3
2
SPI_SEL_A_1
2
SPI_MOSI_1
SPI_MISO_1
Q6
BSN20
3
TP3
GND GND
2
Q4
BSN20
3
TP4
AD7887
0.1uF
+5V_RF U3
2
4
3
2
CS
1
CLPF
5
1
7
6
8
CS
DOUT
AIN0
AIN1/VREF DIN
SCLK
GND
R16
4.7K
1
7
VDD
R13
4.7K
Q1
BSN20
1
VSET
5
4
VOUT
Q2
BSN20
1
6
TEMP
U1
AD8318
GND
VOUT
R20
3.3K
R15
4.7K
1
INLO
C2
13
1000pF
TP9
2
R14
4.7K
1
R17
3.3K
R19
3.3K
1
15
B
GND
TP2
R1
52.3
GND
GND
TP1
CMOP
INHI
VPSO
ENBL
C1
1000pF
14
GND
GND
9
16
GND
U2
VPSI
VPSI
J3
142-0701-801
Coax, Board Edge
3
4
GND
R18
3.3K
3
3
Q7
BSN20
2
SPI_CLK_1
B
Q8
BSN20
ADR421
R2
499
GND
GND
J4
FX8-120S-SV(21)
F
+5V_SDP
+5V_SDP
6
SCL_0
SDA_0
4
24LC32A
Y
GND
R21
20.0
GND
SCL_0
SDA_0
SPI_CLK
SPI_MISO
SPI_MOSI
SPI_SEL_A
GND
SPI_MISO_1
VIN
7
8
IN
IN
6
SD
SPI_SEL_A_1
F1
1210L035YR
350mA - Hold
700mA - Trip
6V
PGND
J2
1
3
2
U4
BNX016-01
1
+6V
PJ-002A
2.1mm X 2.5mm OD
OUT
OUT
OUT
D1
6.8V
1.2V@1A
SMBJ5342B-TP
C11
4.7uF
3
PGND
FB
5
ADP3336
R10
64.9K
7
8
OUT
OUT
OUT
IN
IN
C14
6
1.0uF
TP8
TP6
GND
PGND
+5V_RF
1
2
3
+5V_RF
C15
R11
210K
SD
FB
1.0uF
E
D3
SML-LX15GC
2.2V@20mA
5
ADP3336
R12
64.9K
GND
TP21 TP20 TP19 TP7
1.0uF
TP15
GND
FID1 FID2 FID3
D
C17
U8
VIN
4
5
6
+5V_SDP
GND
D2
TP16
400mV@2A
SBR2U30P1-7
2
+5V_SDP
1
2
3
R9
210K
4
1
2
R8
78.7K
TP14
C16
1.0uF
R24
20.0
J1
ADP3336
U6
SPI_MOSI_1
R23
20.0
1.0uF
5
GND
SPI_CLK_1
R22
20.0
FB
C
C13
74HC1G125
GND
TP10
TP11
TP12
TP13
+3.3V
R7
140K
GND
2
1
TP17
TP18
GND GND GND GND GND
GND
A
OE
1
2
3
SD
GND
GND
OUT
OUT
OUT
IN
IN
4
A0 VCC
WP
A1
SCL
A2
VSS SDA
1.0uF
5
U9
8
7
6
5
VCC
U5
1
2
3
4
R5
100K
7
8
C12
R6
OPEN
R4
100K
VIN
+5V_SDP
+3.3V
GND
E
61
62
63
64
65
66
67
68
69
70
71
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73
74
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104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
4
D
BMODE1
RESET_IN
UART_TX
UART_RX
GND
GND
NC
NC
NC
EEPROM_A0
NC
NC
NC
NC
NC
NC
GND
GND
NC
NC
NC
NC
TMR_D
TMR_C
TIMERS
TMR_B
TMR_A
GPIO7
GPIO6
GND
GND
GENERAL
GPIO5
GPIO4
INPUT/OUTPUT
GPIO3
GPIO2
GPIO1
GPIO0
SCL_0
SCL_1
I2C
SDA_0
SDA_1
GND
GND
SPI_CLK
SPI_SEL1/SPI_SS
SPI_MISO
SPI_SEL_C
SPI
SPI_MOSI
SPI_SEL_B
SPI_SEL_A
GND
GND
SPORT_INT
SPORT_TSCLK
SPORT_DT3
SPORT_DT0
SPORT_DT2
SPORT
SPORT_TFS
SPORT_DT1
SPORT_RFS
SPORT_DR1
SPORT_DR0
SPORT_DR2
SPORT_RSCLK
SPORT_DR3
GND
GND
PAR_CLK
PAR_FS1
PAR_FS2
PAR_FS3
PAR_A0
PAR_A1
PAR_A2
PAR_A3
GND
GND
PAR_INT
PAR_CS
PAR_WR
PAR_RD
PAR_D0
PAR_D1
PAR_D2
PAR_D3
PAR_D4
PAR_D5
GND
GND
PARALLEL
PAR_D6
PAR_D7
PAR_D8
PAR_D9
PORT
PAR_D10
PAR_D11
PAR_D12
PAR_D13
GND
PAR_D14
PAR_D15
GND
PAR_D16
PAR_D17
PAR_D18
PAR_D19
PAR_D20
PAR_D21
PAR_D22
PAR_D23
GND
GND
VIO(+3.3V)
USB_VBUS
GND
GND
GND
GND
NC
NC
NC
VIN
3
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
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25
24
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22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
C
+3.3V
TP22
U7
+3.3V
R3
165
GND
F
1
2
3
+2.3V
VCC2 VCC1
1
5
Y
3
2
3
C14 10uF
.020kGND
R11
C18 .1uF
VCC1 VCC2
6
3
A
5
+3.3V_EEPROM
Y
C22 10uF
.020k GND
1
OE
2
A
R10
F
+5V_SDP
GND
1uF
U10
8
7
6
5
IC_ADG3231
GND C19
10uF
U5
6
VCC2 VCC1
1
5
3
Y
A
GND
6
SD
1
2
3
OUT
OUT
OUT
C27
1uF
4
GND
GND
R22
GND
.020k
GND
R9
GND
C
C28
5
FB
1uF
4
2
24LC32A
C24 10uF
IN
IN
+3.3V
TP6
GND
7
8
R21
GND
A0 VCC
A1
WP
A2
SCL
VSS SDA
R23
1uF
C23 .1uF
GND
NC
Open
R5
R6
100.0k
R4
1
2
3
4
C30
5
FB
B
+3.3V
GND
C20 .1uF
U6
TP19
4
TP17
TP18
GND
TP14
IN
IN
6
SD
SPI_SEL_A
GND
1uF
PGND
3
U8
4
5
6
C2
GND
IN
IN
6
SD
OUT
OUT
OUT
FB
E
1
2
3
5
C3
1uF
GND
GND
GND
D3
SML-LX15GC
2.2V@20mA
1uF
+3.3V_EEPROM
+5V_ANALOG
TP4
GND
7
8
R2
GND GND
6.8V
1.2V@1A
SMBJ53428B-TP
400mV@2A TP3
SBR2U30P1-7
2
165
C1
D1
4.7uF
PGND
U7
BNX016-01
1
R3
PJ-002A
2.1mm X 2.5mm OD
R13
4
1 VIN_JACK
3
2
210k
TP24 TP25
J2
R1
GND GND GND GND
6V
700mA - Trip
350mA - Hold
1210LO35YR
F1
TP2
PGND
GND
1
2
ID1 ID2 ID3
C16
5
FB
1uF
J1
TP20 TP21 TP22 TP23
D
1
2
3
OUT
OUT
OUT
C15
TP1
+5V_SDP
TP5
7
8
210k
TP16
64.9k
SPI_CLK
SPI_MISO
U9
R12
TP15
64.9k
SCL_0
SDA_0
4
E
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
C29
Y
R24
1
2
4
D
SD
GND
GND C17
10uF
GND
+2.3V
100.0k
C
6
1
2
3
OUT
OUT
OUT
4
GND
J4
RESET_IN
BMODE1
UART_RX
UART_TX
GND
GND
NC
NC
EEPROM_A0
NC
NC
NC
NC
NC
NC
NC
GND
GND
NC
NC
NC
NC
TMR_C
TMR_D
TIMERS
TMR_A
TMR_B
GPIO6
GPIO7
GND
GND
GENERAL
GPIO4
GPIO5
INPUT/OUTPUT
GPIO2
GPIO3
GPIO0
GPIO1
SCL_1
SCL_0
I2C
SDA_1
SDA_0
GND
GND
SPI_SEL1/SPI_SS
SPI_CLK
SPI_SEL_C
SPI_MISO
SPI
SPI_SEL_B
SPI_MOSI
GND
SPI_SEL_A
SPORT_INT
GND
SPORT_DT3
SPORT_TSCLK
SPORT_DT2
SPORT_DT0
SPORT
SPORT_DT1
SPORT_TFS
SPORT_DR1
SPORT_RFS
SPORT_DR2
SPORT_DR0
SPORT_DR3
SPORT_RSCLK
GND
GND
PAR_FS1
PAR_CLK
PAR_FS3
PAR_FS2
PAR_A1
PAR_A0
PAR_A3
PAR_A2
GND
GND
PAR_CS
PAR_INT
PAR_RD
PAR_WR
PAR_D1
PAR_D0
PAR_D3
PAR_D2
PAR_D5
PAR_D4
GND
GND
PARALLEL
PAR_D7
PAR_D6
PAR_D9
PAR_D8
PORT
PAR_D11
PAR_D10
PAR_D13
PAR_D12
PAR_D14
GND
GND
PAR_D15
PAR_D17
PAR_D16
PAR_D19
PAR_D18
PAR_D21
PAR_D20
PAR_D23
PAR_D22
GND
GND
USB_VBUS
VIO(+3.3V)
GND
GND
GND
GND
NC
NC
VIN
NC
IN
IN
GND
GND
D2
GND
IC_ADG3231
+2.3V
TP7
7
8
5
GND
U4
+3.3V_EEPROM
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
U11
+3.3V
C21 .1uF
97.6k
+3.3V
102.5k
+2.3V
GND VCC
GND
A
140k
4
5
R16
U3
6
78.7k
NC
NC
GND
R8
1.43k
A
3
GND
9
4
2
VIN
CS
SDATA
SCLK
GND C12
10uF
GND
NC
8
VDD
6
2k
7
IC_ADG3231
TP13
TP12
1TP11
NC
GND
GND
8
C13 .1uF
U1
IC_ADL5902_LFCSP_VQ
GND
7
+3.3V
C11 .1uF
IC_AD7466_TSSOP8
TP9
1.21k
R14
6
U2
GND
TP8
R17
1
VSET
C26
10uF
GND
3.74k
11
VOUT
C25
.1uF
7
R18
2k
10
VPOS2
NC
NC
NC
.1uF
VTGT
12
2
13
16
100pF
8
TADJ/PWDN
COMM
COMM
COMM
C6
TEMP
301
CLPF
C5
GND
R15
INLO
5
6
GND
GND
VREF
15
5
TP10
C8
3
INHI
VPOS1
14
4
9
17
B
60.4
R7
C4
J3
100pF
GND
100pF
C9
A
.1uF
C10
C7
.1uF
GND
4
+5V_ANALOG
100pF
+5V_ANALOG
F
GUIA DE USO DEL ANALIZADOR DE CAMPOS ELECTROMAGNÉTICOS SRM-3006
DEL NARDA SAFETY TEST SOLUTIONS
A continuación se describirán los pasos realizados a la hora de analizar los puntos
medidos por el equipo SRM-3006.
1. El equipo viene con el software SRM-3006_Tools, el cual te permite realizar
operaciones básicas como la de configurar el equipo según la medición a realizar,
descargar y visualizar los datos almacenados en el equipo, entre otras opciones
básicas. Como se necesita trabajar con los datos almacenados, se necesita
descargar el software SRM-3006_TS, el cual te permite una evaluación de los
datos, para el caso de la presente tesis, te permite realizar la integración del todo
el rango medido.
2. Una vez descargo el software e importado todos los puntos medidos almacenados
en el equipo (en formato .CSV), se procederá a trabajar con las mediciones.
Para ello se debe crear una database en formato .srmdb, realizando los siguientes
pasos: File>New>Database como se observa en la figura 1.
Figura 1: Creación de una database en el software SRM-3006_TS
3. Luego de haber creado la database, se procederá a almacenar toda la data
importada del analizador dentro del archivo .srmdb creado. Para ello en la pestaña
Database debajo del pestaña Import/Export se encuentra la opción Data. Luego de
darle clic, se abrirá el cuadro de la figura 2. Allí se selecciona Folder, ya que en mi
caso importe una gran cantidad de datos y los almacené una carpeta (folder),
luego seleccionas la ubicación del folder y finalmente te aparecerá la figura 3, con
todos los datos que se encontraron en tu folder. Seleccionas lo que se requieren,
en mi caso todo, y le das a la opción Save.
Figura 2: Cuadro de importación de datos
Figura 3: Cuadra de selección de datos a analizar
4. Luego se empezaran a importar toda la data seleccionada (figura 4) y se podrá
visualizar cada punto medido en la parte inferior izquierda, en el cuadra Database.
Finalmente se selecciona el dato y en la esquina derecha inferior se encuentra
habilitada el cuadro de Evaluation, en donde se encuentra la opción Integration. Se
puede realizar la integración de manera manual en la misma grafica o bien
seleccionando una frecuencia de integración mínima o máxima (figura 5).
Figura 4: Importación de los datos en la archivo database creado
Figura 5: Evaluación de uno de los datos importados
Elaborado por Giancarlo Villena Prado
RESULTADOS DE LAS PRUEBAS DEL SISTEMA
Como se mencionó en el documento de tesis, los resultados fueron analizados a través de
la herramienta API de Google Maps. A continuación se escribirán los URL’s donde se
puede analizar con mayor detalle cada punto analizado según la prueba realizada:
1. Pruebas realizadas a nivel del suelo:

Prueba con la antena de retorno de 850 MHz
https://www.google.com/fusiontables/DataSource?docid=1vIPyIPD416j_5FfYPz_-rczxCwhib-JDq4x2bUX#map:id=3

Prueba con la antena de retorno de 1900 MHz
https://www.google.com/fusiontables/DataSource?docid=1xHSgUc9fNnzYJ
-eid7jwPIHdhL7ScaOS0_4vcYsO&pli=1#map:id=3
2. Pruebas realizadas en el drone alrededor de la antena de telefonía celular:

Prueba con la antena de retorno de 850 MHz
https://www.google.com/fusiontables/DataSource?docid=1bcI5O7JUrGrXqTD2Pyfwg5di53QpBS6n-0CMVR6#map:id=3

Prueba con la antena de retorno de 1900 MHz
https://www.google.com/fusiontables/DataSource?docid=1tgQ1_rEmwQhw
8svLCCdyuGjq7zc1UV2Z2-RNrD57&pli=1#map:id=3