DTV Converter Box Test Program-- Results and Lessons Learned October 9, 2009 Technical Research Branch Laboratory Division Office of Engineering and Technology Federal Communications Commission OET Report Prepared by: FCC/OET 9TR1003 Stephen R. Martin ACKNOWLEDGMENTS AND DISCLAIMER This report presents information gained from a test program conducted by the Federal Communications Commission (FCC) Laboratory on behalf of the National Telecommunications and Information Administration (NTIA). This data is being presented for informational purposes only. The findings and conclusions in this report are those of the author. This report does not represent and should not be construed to represent a formal determination or policy by the Federal Communications Commission, the Office of Engineering and Technology, or the National Telecommunications and Information Administration. The author gratefully acknowledges the following contributions to this work. • Anita Wallgren, Program Director of the Digital-To-Analog Converter Box Coupon Program, along with her team at the NTIA, provided the FCC Laboratory with the opportunity and funding to conduct the test program on which this report is based. Ms Wallgren, Jeff Wepman, and Charles Mellone of the NTIA provided valuable guidance during the project. • Scot Hudson, Leon Teat, Mark Besmen, Patrick Brown, and John Colmer conducted most of the 50,000 tests that formed the basis for this report while working on-site at the FCC Laboratory under contract through Computer Servants. • Jeff Wepman and Anita Wallgren of the NTIA, and Dr. Rashmi Doshi, William Hurst, John Gabrysch, Gordon Godfrey, and Doug Miller of the FCC reviewed drafts of this report and provided many suggestions that improved the final version. i This page is intentionally blank ii TABLE OF CONTENTS CHAPTER 1 INTRODUCTION............................................................................................................................... 1-1 Background........................................................................................................................................................... 1-2 Objectives ............................................................................................................................................................. 1-2 Overview............................................................................................................................................................... 1-3 CHAPTER 2 RF PERFORMANCE OF APPROVED CONVERTER BOXES....................................................... 2-1 Test Methodology and Terminology..................................................................................................................... 2-2 Minimum Input Signal (Sensitivity) ..................................................................................................................... 2-3 Maximum Input Signal (Overload)....................................................................................................................... 2-6 Phase-Noise And Burst-Noise Rejection .............................................................................................................. 2-6 NTSC Interference Susceptibility (Co-Channel or Adjacent-Channel) ................................................................ 2-7 Susceptibility to Interference from Single DTV Signals on Adjacent and Taboo Channels................................. 2-8 Susceptibility to Interference from A Pair of DTV Signals ................................................................................ 2-14 RF Pass-Through ................................................................................................................................................ 2-17 CHAPTER 3 MULTIPATH PERFORMANCE OF APPROVED CONVERTER BOXES..................................... 3-1 Background........................................................................................................................................................... 3-1 Single-Static-Echo Tests....................................................................................................................................... 3-2 Field-Ensemble Tests............................................................................................................................................ 3-3 Relationship Between Single-Static-Echo and Field-Ensemble Results............................................................... 3-5 CHAPTER 4 EFFECTS OF TUNER IMPLEMENTATION.................................................................................... 4-1 Background........................................................................................................................................................... 4-1 Susceptibility to Interference from Single DTV Signals on Adjacent and Taboo Channels................................. 4-2 Susceptibility to Interference from an Equal-Amplitude Pair of DTV Signals..................................................... 4-5 Susceptibility to Interference from an Unequal-Amplitude Pair of DTV Signals .............................................. 4-12 CHAPTER 5 EFFECTS OF RF-PASS-THROUGH IMPLEMENTATION ............................................................ 5-1 Background........................................................................................................................................................... 5-1 Sensitivity ............................................................................................................................................................. 5-2 Susceptibility to Interference from Single DTV Signals on Adjacent and Taboo Channels................................. 5-3 Susceptibility to Interference from a Pair of DTV Signals ................................................................................... 5-4 CHAPTER 6 POWER CONSUMPTION OF APPROVED CONVERTER BOXES............................................... 6-1 CHAPTER 7 FAILURES TO SATISFY NTIA REQUIREMENTS ........................................................................ 7-1 Overview of Failures to Satisfy NTIA Requirements........................................................................................... 7-1 Failures in Basic Functionality ............................................................................................................................. 7-3 Failures to Handle All Video Modes .................................................................................................................... 7-3 Failures in Information Display and Control ........................................................................................................ 7-5 Failures in Output Quality .................................................................................................................................. 7-13 Failures in RF DTV Reception Performance (Excluding Multipath) ................................................................. 7-14 Failures in Multipath Performance ..................................................................................................................... 7-20 Failures in RF Pass-Through Performance ......................................................................................................... 7-22 Failures in RF Emissions .................................................................................................................................... 7-23 Adding Channels to a Previous Channel-Scan.................................................................................................... 7-23 CHAPTER 8 ISSUES INVOLVING TECHNICAL REQUIREMENTS AND STANDARDS............................... 8-1 CHAPTER 9 LESSONS LEARNED FOR FUTURE DTV RECEIVER TESTING................................................ 9-1 Video Mode Testing ............................................................................................................................................. 9-1 Daylight Savings Time Testing ............................................................................................................................ 9-1 Parental Control Testing ....................................................................................................................................... 9-2 AGC Memory / Hysteresis.................................................................................................................................... 9-2 TOV Versus Signal Acquisition Levels................................................................................................................ 9-3 Channel-37 Interference........................................................................................................................................ 9-3 Double TOVs for some paired interferer tests ...................................................................................................... 9-3 Unexpected Channel Dependencies...................................................................................................................... 9-4 Intentional Phase Noise Vulnerability Tests......................................................................................................... 9-5 Unintended Phase Noise of Signal Sources in RF Performance Tests.................................................................. 9-5 Summary of Testing Lessons Learned...............................................................................................................