Document Revision No.: 3 Revised 05/11/2012 Jared Burdick
RIT SENIOR DESIGN PROJECTSingle-Balanced Mixer
Final Test Plan
Jared P. Burdick
5/11/2012
Single-Balanced Mixer Project
Test Plan & Test Results
Table of Contents
1. PRELIMINARY TEST PLAN 3
1.1. Sub-Systems / Functions / Features 3
1.2. Template 4
1.3. Test Equipment 4
2. TEST PLAN 5
2.1. Data Collection 5
2.1.1. Data Collection Structure 5
2.1.2. Sampling Techniques 5
2.1.2.1. Test 1 – Conversions Loss Measurements 5
2.1.2.1.1. Test Description – Conversion Loss 5
2.1.2.1.2. Test Set-up – Conversion Loss 6
2.1.2.1.3. Test Conditions – Conversion Loss 8
2.1.2.2. Test 2 – RF to IF Isolation Measurements 8
2.1.2.2.1. Test Description – RF to IF Isolation 8
2.1.2.2.2. Test Set-up – RF to IF Isolation 8
2.1.2.2.3. Test Conditions – RF to IF Isolation 9
2.1.2.3. Test 3 – LO to IF Isolation Measurements 9
2.1.2.3.1. Test Description – LO to IF Isolation 9
2.1.2.3.2. Test Set-up – LO to IF Isolation 10
2.1.2.3.3. Test Conditions – LO to IF Isolation 10
2.1.2.4. Test 4 – 1dB Compression Point Measurements 11
2.1.2.4.1. Test Description – 1dB Compression Point 11
2.1.2.4.2. Test Set-up – 1dB Compression Point 11
2.1.2.4.3. Test Conditions – 1dB Compression Point 12
2.1.2.5. Test 5 – VSWR (Return Loss) Measurements 12
2.1.2.5.1. Test Description – Return Loss (VSWR) 12
2.1.2.5.2. Test Set-up – Return Loss (VSWR) 12
2.1.2.5.3. Test Conditions – Return Loss (VSWR) 13
2.1.2.6. Test 6 – Spurious Output Measurements 13
2.1.2.6.1. Test Description – Spurious Output 14
2.1.2.6.2. Test Set-up – Spurious Output 14
2.1.2.6.3. Test Conditions – Spurious Output 14
2.1.3. Sample Size 15
2.1.4. Reporting Problems - Corrective Action 15
2.2. Test Procedure & Timeline 15
3. DESIGN VERIFICATION 15
3.1. Logistics 15
3.2. Analysis of Data - Design Summary 15
3.3. Conclusion / Design Summary 16
3.3.1. Lab Demo 16
3.3.2. Meeting with Sponsor 16
APPENDIX 1: Test Data Templates 17
1. PRELIMINARY TEST PLAN
1.1. Sub-Systems / Functions / Features
This test plan document provides structure to the overall evaluation and verification of the prototype Single-Balanced Mixer design. The plan considers the lower-level elements (e.g. Functions or sub-circuits) as well as the top-level “system” which is the final mixer itself. The plan will incorporate element simulations, element evaluations (measurements), top-level (system) simulations and final product measurements. The goal is to develop an approach for analyzing (simulating) and/or measuring lower –level blocks and the complete system that is practical to implement given the constraints of the project. The major constraints are time, cost, and availability of test equipment. These will limit the ability to measure all sub-circuits as in many cases custom test fixtures would have to be designed, fabricated and built, or access to specific test equipment may not be readily available. The plan will identify what alternate approaches have been taken as well as any associated risk. Ultimately, the final unit will be tested for the specified parameters, however, should the final unit not meet any performance requirements the lower-level evaluations would be helpful in identifying the cause, and eventually, the corrective actions.
The block diagram for the single-balanced mixer is shown in the figure below. Each major element (function) is identified and has a reference designation number that will be used later.
All of the major sub-systems (elements) are listed in the table below with the reference designation from the block diagram.
1.2. Template
The preliminary test data template is included in Appendix A. This format is subject to change prior or after measurements. It is anticipated that modifications will be minor and performed only to clarify presented results.
1.3. Test Equipment
Testing of the completed mixer prototype will take place at Anaren. It has been verified that Anaren has all of the equipment required and will make them available when needed.
The list of Test equipment to be utilized is listed in the Table below.
2. TEST PLAN
2.1. Data Collection
2.1.1. Data Collection Structure
2.1.2. Sampling Techniques
2.1.2.1. Test 1 – Conversions Loss Measurements
2.1.2.1.1. Test Description – Conversion Loss
Conversion Loss is the measurement of the drop in power level of the RF Input signal to the converted corresponding IF Output signal. This will be measured by connecting the Mixer (Unit Under Test or UUT) as shown in 2.2.1.2 (Figure 1). The UUT will be supplied with the LO drive input (Signal Generator 2) and RF input signal (Signal Generator 1) and the IF output signal will be connected to the Spectrum Analyzer as shown. Calibration of the set-up will need to be performed prior to measuring the UUT. After calibration, the RF Input signal will be stepped through frequencies and the fundamental IF output power will be measured with the Spectrum Analyzer. Final loss numbers will be corrected with the calibrated correction factors as described below. This test will be performed with the maximum RF power level and the minimum LO input drive level as specified. Additionally, 2 full swept-frequency plots (0.8 to 1.0 GHz and 1.0 to 1.2 GHz) will be recorded from the spectrum analyzer to verify that no unusual frequency response points exist in-between the discrete measured points.
2.1.2.1.2. Test Set-up – Conversion Loss
The test set-up is as shown below in Figure 1.
Equipment Required: As shown in Figure 1 using the equipment listed in 1.3. Three suitable test cables will also be required to connect the RF Signal Generators and Network Analyzer to the UUT as well as appropriate test adapters. A DC block will be incorporated at the input to the Spectrum Analyzer to avoid damage to the equipment.
Calibration: First the RF Input level will be calibrated for the level specified in 2.1.2.1.3. The Power Meter will be first calibrated and zeroed by connecting it to its internal RF source and running its embedded routine. Once zeroed, the meter will be connected to the cable at the end of RF Signal Generator 1 (RF). The RF Generator will then be stepped through the test frequencies per 2.1.2.1.3 and the output level of the Signal Generator will be adjusted to produce a -10.0 dBm level as measured with the Power Meter. The output power setting of the Signal Generator will then be recorded in the Conversion Loss table of Appendix 1 in the "RF Gen Setting" section, under the “RF Gen Level” column next to the appropriate frequency. This will be repeated for all test frequencies listed.
Next the Spectrum Analyzer will be calibrated for measuring power levels over the IF band. For this calibration, RF Signal Generator 1 (RF) will again be connected to the Power Meter with its cable. The frequency will be stepped through the first 9 points listed in the table of Appendix 1 (Test Steps 1-9) in the IF Power Level Calibration section. The output power level of the generator will be set to -10 dBm nominal and not changed during the calibration. The power level reading from the power meter will be recorded under the “Pwr Mtr Level” column. Once all of the test frequencies are completed, the cable will then be connected to the Spectrum Analyzer (with the DC Block connected to its input). The Spectrum Analyzer will be set for an IF band from its lowest frequency (9 KHz) to 250 MHz. Resolution and Video BW’s will be automatically set. The Reference Level will be set to -5 dBm and the scale to 1dB/division. The signal generator will again be stepped through the same frequencies (without touching the amplitude level) and the power level will be read off the Spectrum Analyzer by using the Peak Search Marker function and recorded in the “Sp An Level” column.
These values collected will then be entered into an Excel workbook and the correction factors will be calculated and filled into the spreadsheet (as well as the IF data from Test Steps 10-17). Calibration/Correction is now complete.
Measurements: First the RF Signal Generator 2 (LO) will be connected to the Power Meter with its cable, the frequency set per 2.1.2.1.3 and at the specified power level. The signal generator will be adjusted to produce the specified output level and then connected to the LO Input port of the UUT.
Next, RF Signal Generator 1 (RF) will be connected to the RF Input port and the IF Output port will be connected to the Spectrum Analyzer (DC Block included). The RF Input frequency will be stepped through the test frequencies listed in Appendix 1 with the output level being adjusted to the corrected setting listed for each frequency (to produce a known -10 dBm signal). The Spectrum Analyzer (with the same settings specified in the calibration section, except the Reference Level will be set to -10 dBm) will be used to measure the fundamental output (IF) power level using the Peak Search Marker function. The level read will be recorded in the "Conversion Loss Calculation Section" of Appendix 1 under the “Sp An Level” column.
Finally, 2 swept plots will be generated to show the continuous shape of the IF output fundamental level. For this, the RF Generator 1 (RF) will be set to sweep from 0.7 GHz to 1.3 GHz (100 MHz beyond the operating range). Note the “sweep” will be manual as the generator used does not have automatic swept capability. The Spectrum Analyzer will be set to for a range of 9 kHz to 300 MHz. The Max Hold function will be selected and the signal generator will be slowly varied from 0.7 to 1.0 GHz and the resulting plot will be saved to disk. This will be repeated over the RF frequency range of 1.0 to 1.3 GHz.
Data Formats: Once the data has been recorded it will be entered into the Excel worksheet and the data will automatically be corrected. The workbook will also produce several plotted graphs. The plots taken will also be included.
2.1.2.1.3. Test Conditions – Conversion Loss
The test conditions for the conversion loss measurements areas indicated in the table below.
2.1.2.2. Test 2 – RF to IF Isolation Measurements
2.1.2.2.1. Test Description – RF to IF Isolation
RF to IF Isolation is a measure of the RF signal “leakage” present at the IF Output port. This will be measured by connecting the Mixer (Unit Under Test or UUT) as shown in 2.1.2.2.2 (Figure 2). The UUT will be supplied with the LO drive input (Signal Generator 2) with the IF output signal connected to the Spectrum Analyzer as shown. Calibration of the set-up will need to be performed prior to measuring the UUT. After calibration, the level of RF signal present at the IF output port will be measured and compared against the RF input level.
2.1.2.2.2. Test Set-up – RF to IF Isolation
The test set-up is as shown below in Figure 2.
Equipment Required: As shown in Figure 2 using the equipment listed in 1.3. Three suitable test cables will also be required to connect the RF Signal Generators and Network Analyzer to the UUT as well as appropriate test adapters. A DC block will be incorporated at the input to the Spectrum Analyzer to avoid damage to the equipment.
Calibration: The RF input from RF Input Signal Generator 1 (RF) will use the same corrected output power settings as determined in the Calibration section of the Conversion Loss Measurement (2.1.2.1.2), assuming the measurements are performed within a reasonable time after the calibration (within 6 hours). If not, the calibration should be repeated.
Measurements: The LO Input will be connected to RF Signal Generator 2 (LO) set per 2.1.2.2.3. The IF Output port will be connected to the Spectrum Analyzer and the Signal Generator 1(RF) will be connected to the UUT RF Input port. Signal Generator 1 (RF) will be stepped through the test frequencies as defined in 2.1.2.2.3 with the output power corrected for -10 dBm for each frequency. The Spectrum Analyzer will be set for a band of 750 MHz to 1250 MHz with a reference level of -10 dBm and 1 dB per division. The level of the RF signal at the IF output will be measured using the Marker function set to the test frequency and recorded in Appendix 1 under the “RF Level at IF Out”.
Data Formats: Data will be hand recorded into a table as shown in Appendix 1 and then transferred into the Excel workbook where the Isolation figure will be calculated automatically (RF Input Level minus the RF Level at the IF Output).
2.1.2.2.3. Test Conditions – RF to IF Isolation
The test conditions for the LO to RF Isolation measurement is as indicated in the table below.
2.1.2.3. Test 3 – LO to IF Isolation Measurements
2.1.2.3.1. Test Description – LO to IF Isolation
LO to IF Isolation is the LO signal “leakage” present at the IF Output port. This will be measured by connecting the Mixer (Unit Under Test or UUT) as shown in 2.1.2.2.2 (Figure 3). The UUT will be supplied with the LO drive input (Signal Generator 2) with the IF output signal connected to the Spectrum Analyzer as shown. Calibration of the set-up will need to be performed prior to measuring the UUT. After calibration, the level of LO signal present at the IF output port will be measured and compared against the LO input level.
2.1.2.3.2. Test Set-up – LO to IF Isolation