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Television Receiving Antenna System Component Measurements

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NTIA-REPORT-79-22 Television Receiving Antenna System Component Measurements R.G. FitzGerrel R.D. Jennings J.R. Juroshek us, DEPARTMENT OF COMMERCE Juanita M. Kreps, Secretary Henry Geller, Assistant Secretary for Communications and Information June 1979 TABLE OF CONTENTS 1. LIST OF FIGURES iv 2. LIST OF TABLES x 3. ABSTRACT 1 4. INTRODUCTION 1 5. DEFINITIONS AND TERMINOLOGY 2 2.1 Voltage Standing Wave Ratio (VSWR) and Mismatch Loss 2 2.2 Insertion Loss 3 2.3 System Loss 4 2.4 Antenna Gain 4 6. ANTENNA CONSTANT 6 7. ANTENNA GAIN MEASUREMENTS 8 8. BALUN INSERTION LOSS 24 9. SIGNAL SPLITTER INSERTION LOSS 24 10. VSWRtS OF ANT$NNAS, BALUNS, AND SPLITTERS 28 11. TRANSMISSION LINE LOSS 32 12. DISCUSSION-CONCLUSIONS 37 13.' REFERENCES 41 APPENDIX. MEASURED RELATIVE GAIN PATTERNS 43 iii, LIST OF FIGUIm~ Figure 1. Typical single-set, single-antenna TV installations 5 A. Indoor antenna on receiver, VHF or UHF. B. Antenna to receiver with "twin lead" trans­ mission line, VHF or UHF. C. Antenna to receiver ·with "twin lead" trans- mission line, VHF and UHF. D. Antenna to receiver with coaxial cable trans­ mission line, VHF and UHF. Figure 2. Dipole antenna constant versus frequency. 7 Figure 3. Typical VHF antenna gain pattern measured at 183 MHz 10 {channel 8). The gain increments are 5 dB and the reference dipole gain level is shown by the circle on the 180 deg - 0 deg axis. Figure 3. Typical UHF antenna gain pattern measured at 641 MHz 11 (channel 42). The gain increments are 5 dB and the reference dipole gain le·vel is shown by the circle on the 180 deg - 0 deg axis. Figure 5. Typical half-wave dipole reference antenna gain 12 pat.tern. The gain increments are 5 dB. Figure 6. Schematic drawing of insertion loss ·measure.ment system. 26 Figure 7. Schematic drawing of splitter insertion lossmeasure- 27 ment system. Connections shown are for the UHF tests. Figure 8. Schematic drawing of VSWR measurement system. 31 Figure 9. Attenuat.ion bounds (best and worst case) versus 33 frequency for new, dry 300-ohm balanced transmission line, derived from manufacturers' data. Figure 10. Attenuation bounds (best and worst case) versus 35 frequency for new, dry RG-6 type coaxial cable, derived from manufacturers' data. Figure 11. Attenuation bounds (best and worst case) versus 36 frequency for new, dry RG-59 type coaxial cable, derived from manufacturers' data. iv LIST OF FIGURES (cont.) Page Figure 12. Increase in line loss because of standing waves (SWR 38 value at the load). To determine the total loss in decibels in a line having an SWR greater than 1, f i.rst; determine the loss for the particular type of line, length and frequency, on the assumption that the line is perfectly matched. Locate this point on the horizontal axis and move up to the curve corresponding to the actual SWR. The corresponding value on the vertical axis gives the additional loss in decibels caused by the standing waves. Figure 13. Graphical presentation of the range of the power budget 40 equation versus frequency for the four systems considered. To convert the P scale to dB relative to 10-6V rec at the 300 ohm receiver terminals with a field strength of 60 dB relative to 10-6V/ m at the antenna, add 59 dB. Figure 14. Measured ant.enna gain versus frequency. 42 Figure A-1 ~ Relative gain pattern in the azimuthal plane at 63 MHz 44 for antenna No. 1. Figure A-2. Relative gain pattern in the azimuthal plane at 79 MHz 45 for antenna No. 1. Figure A-3. Relative gain pattern in the azimuthal plane at 183 r-1Hz 46 for antenna No. 1. Figure A-4. Relative gain pattern in the azimuthal plane at 213 MHz 47 for antenna No. 1. Figure A-S. Relative gain pattern in the azimuthal plane at 63 MHz 48 for antenna No. 2. Figure A-6. Relative gain pattern in the azimuthal plane at 79 MHz 49 for antenna No. 2. Figure A-7. Relative gain pattern in the azimuthal plane at 183 MHz 50 for antenna No. 2. Figure A-8. Relative gain pattern in the azimuthal plane at 213 MHz 51 for antenna No. 2. Figure A-9. Relative gain pattern in the azimuthal plane at 63 r1Hz 52 for antenna No. 3. Figure A-10. Relative gain pattern in the azimuthal plane at 79 MHz 53 for antenna No. 3. V LIST OF FIGURES (cont.) Figure 1\-11. Re,lative gain pattern in the azimuthal plane at18J MHz 54 for antenna No.3. Figure A-12. Relative gain pa.ttern in the azimuthal plane at 213 MHz 55 fot' antenna No.3. Figure A-13. Relative gain pat,t,ern in the azimuthal plane at 63 MHz 56 for antenna No •. 4., Figure A-14. Relative gain pattern in the aziimut.hal. plane at. 79 MHz 57 f ell" antenna No.4. Figure A-15. Relativeqain pattern in the azimuthal plane at 183 MHz 58 for antenna No.4. Figure A-16. Relative ga,inpatternin the azimuthal plane at 213 MHz 59 f or antenna No.. 4. Figure 1\-1'. Relative gain pattern in the azimuthal plane at 63 MHz 60 for antenna No. S. Antenna. was mounted on test stand 90 deg off Q,ptical If:boresight'' to tra.nsmltting; a,!l,tenna. Fig:ure A-18. Relative gain patter'n in the azimuthal plane at 79' MHz 61 for an,tenna No .. 5. A,n,tenna was mounted on test stand 90 deq off opt..leal 'Jbo;r'esight. tt to tra,nsmitting a.ntenna. Figure A~t9. Relative 9'ain pattern in the azimuthal plane at 183 MHz 62 for a.ntenna No.5. Antenna was mounted on test sta.nd 90 deg off optical "boresight" to· transmit,ting an,tenna.. Relative gain pat.t,ern in the azimuthal plan.e at 213 MHz 63 for antenna No.5. Ant.enna was mounted on te,s;t stand 90 deg off opt.ical ·'bore·sight" to transmitting ancerma, Fi.g'ure A-21. Rela,tive gain. pattern in·t.he 'azimuthal pIa.ne at, 63 MHz 64 for antenna No'. 6. Relative gain pattern in, the azimuthal plane. at 79 MHz for antenna NQ.. 6.• Figure A-23. Relative gain pattern in theazimu'thal plane at 18'3 MHz 66 for anten,na' No.6. Figure A-24. Relat"ive gain pattern in the azimuthal plane at 213 MHz 67 for antenna No.· 6. vi LIST OF FIGURES (cont.) Figure A-2S. Relative gain pattern in the azimuthal plane at 413 MHz 68 for antenna No.6. Figure A-26. Relative gain pattern in the azimuthal plane at 641 MHz 69 for antenna NQ. 6. Figure A-27. Relative gain pattern in the azimuthal plane at 803 MHz 70 for antenna No.6. Beam splitting can be noted. Figure A-2S. Relative gain pattern in the azimuthal plane at 63 MHz 71 for antenna No.7. Figure A-29. Relative gain pattern in the azimuthal plane at 79 MHz 72' for antenna No.7. Figure A-30. Relative gain pattern in the azimuthal plane at 183 MHz 73 for antenna No.7. Figure A-31. Relative gain pattern in the azimuthal plane at 213 MHz 74 for antenna No.7. Figure A-32. Relative gain pattern in the azimuthal plane at 473 MHz 75 for antenna No.7. Figure A-33. Relative gain pattern in the azimuthal plane at 641 MHz 76 for antenna No.7. Figure A-34. Relative gain pattern in the azimuthal plane at 803 MHz 77 for antenna No.7. Figure A-3S. Relative gain pattern in the azimuthal plane at 63 MHz 78 for antenna No. B. Figure A-36. Relative gain pattern in the azimuthal plane at 79 MHz 79 for antenna No.8. Figure A-37. Relative gain pattern in the azimuthal plane at 183 MHz 80 for antenna No.8. Figure A-38. Relative gain pattern in the azimuthal plane at 213 MHz 81 for antenna No.8. Figure A-39. Relative gain pattern in the azimuthal plane at 473 MHz 82 for antenna No.8. Figure A-40. Relative gain pattern in the azimuthal plane at 641 MHz 83 for antenna No.8. Figure A-41. Relative gain pattern in the azimuthal plane at 803 Mhz 84 for antenna No.8. vii LIST OF FIGURES (cont.) Page Figure A-42. Relative gain pattern in the azimuthal plane at 63 MHz 85 for antenna No. 9. Figure A-43. Relative gain pattern in the azimuthal plane at 79 MHz 86 for antenna No. 9. Figure A-44. Relative gain pattern in the azimuthal plane at 183 r~Hz 87 for antenna No. 9. Figure A-45. Relative gain pattern in the azi.mut.haL plane at 213 MHz 88 for antenna No. 9. Figure A-46. Relative gain pattern in the azimuthal plane at 473 MHz 89 for antenna No. 9. Figure A-47. Relative gain pattern in the azimuthal plane at 641 MHz 90 for antenna No.9. Figure A-48. Relative gain pattern in the azimuthal plane at 803 MHz 91 for antenna No. 9. Figure A-49. Relative gain pattern in the azimuthal plane at 473 MHz 92 for antenna No. 10. Figure A-50. Relative gain pattern in the azimuthal plane at 641 MHz 93 for antenna No. 10. Figure A-51. Relative gain pattern in the azimuthal plane at 803 MHz 94 for antenna No.
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