Transcript DTV Reception & Consumer Antennas

DTV Reception and
Consumer Antennas
2005 PBS Technology Conference
Kerry W. Cozad
Dielectric Communications
Raymond, Maine USA
Purpose for Study
> Document measured performance of typical
receive antennas
> Provide information to update “planning
factors”
> Assist station engineers in discussions with
viewers
ATSC PS/WP3
Receiver Planning Factors
Testing Methods
> CEA Guidelines
> Outdoor Range
> Computer Modeling
Antenna Parameters
> Principal plane patterns
> Azimuth
> Elevation
> Polarization Response
> Horizontal
> Vertical
Antenna Parameters
> Frequency Response
> Variations within design band
> Response out of design band
> Directivity
> Gain
Antenna Products Tested
> “Set Top”
>
>
>
>
Zenith Silver Sensor 
Megawave
Radio Shack 15-1864 loop 
Terk Antenna Pro
Antenna Products Tested
> Attic or Outdoor
>
>
>
>
RCA ANT3002 VHF/UHF
Winegard PR-8800
Channel Master 4228 
Winegard SS-1000 SquareShooter 
Test Range
Source Antenna
Antenna Under Test
Sample Test Results
Typical Receive Antennas
Remember: Choose your standard carefully.
Coat Hanger UHF Patterns
0
0
330
0.0
330
30
-10.0
270
-10.0
300
60
-15.0
-15.0
-20.0
-20.0
90
-25.0
240
120
210
150
180
Azimuth
30
-5.0
-5.0
300
0.0
270
60
90
-25.0
240
120
210
150
180
Elevation
Radio Shack 1864
Radio Shack 1864 UHF Patterns
0
330
0.0
0
30
330
-5.0
60
-10.0
300
-15.0
-20.0
90
-25.0
240
120
210
150
180
Azimuth
60
-15.0
-20.0
270
30
-5.0
-10.0
300
0.0
270
90
-25.0
240
120
210
150
180
Elevation
Radio Shack 1864 VSWR
CH1
RFL
1 U FS
1_: 20.618
24.24
8.2084 nH
470.000 000 MHz
1
PRm
2_: 62.477
-8.0352
545 MHz
Cor
3_: 28.424
17.364
611 MHz
3
4
4_: 26.878
3.6807
725 MHz
2
CH2
RFL
SWR
500 m /
REF 1
1_ 3.0828
470.000 000 MHz
PRm
2_ 1.3038
545 MHz
Cor
3_ 2.0531
611 MHz
1
4_ 1.8751
725 MHz
3
START 470.000 000 MHz
2
4
STOP 806.000 000 MHz
3:1
2:1
Zenith Silver Sensor
Zenith Silver Sensor UHF Patterns
0
0
330
0.0
330
30
-10.0
270
-10.0
300
60
-15.0
-15.0
-20.0
-20.0
90
-25.0
240
120
210
150
180
Azimuth
30
-5.0
-5.0
300
0.0
270
60
90
-25.0
240
120
210
150
180
Elevation
Zenith Silver Sensor VSWR
CH1
RFL
1.001 U F
1_ 18.216
11.035
3.7368 nH
470.000 000 MHz
PRm
2_ 82.438
30.254
545 MHz
1
Cor
3_ 40.816
-14.08
611 MHz
2
4
4_ 17.329
3.7559
725 MHz
3
CH2
RFL
SWR
500 m /
REF 1
1_: 2.8976
470.000 000 MHz
PRm
2_: 1.9697
545 MHz
Cor
3_: 1.4477
611 MHz
1
4_: 2.9037
725 MHz
3:1
4
2:1
2
START 470.000 000 MHz
3
STOP 806.000 000 MHz
NEC Model of Zenith Silver Sensor
NEC Model of Zenith
Silver Sensor AZ Pattern
NEC Model of Zenith Silver Sensor
AZ Pattern
0
330
0.0
30
-5.0
-10.0
300
60
-15.0
-20.0
270
90
-25.0
240
120
210
150
180
Channel Master 4228
Channel Master 4228 UHF
Patterns
0
0
330
330
30
300
60
270
300
90
240
120
210
150
180
Azimuth
30
60
270
90
240
120
210
150
180
Elevation
Comparison of Measured to
Calculated
0
330
30
300
60
270
90
240
120
210
150
180
Channel Master 4228 VSWR
CH1
RFL
1 U FS
1_ 18.403
-3.8379
88.233 pF
470.000 000 MHz
PRm
Cor
2_ 23.111
8.7373
545 MHz
3
3_ 21.503
27.289
611 MHz
1
2
4
4_ 123.64
40.734
725 MHz
CH2
RFL
SWR
500 m /
REF 1
1_: 2.7355
470.000 000 MHz
PRm
2_: 2.2464
545 MHz
Cor
SCALE
500 m /div
3_: 3.1281
611 MHz
4_: 2.7867
725 MHz
1
3:1
3
4
2
START 470.000 000 MHz
2:1
STOP 806.000 000 MHz
Winegard Square Shooter
Spec Sheet Data
Beamwidth
61°
Avg. VSWR across band
1.3:1
Avg. Front to Back
13db
Avg. gain across band 470-806
4.5db
Max. Width Housing
16" x 16" x 4"
© 2003 Winegard Company. All Rights Reserved
Winegard Square Shooter UHF
Patterns
0
330
0.0
0
30
330
-5.0
270
-10.0
300
60
-15.0
-15.0
-20.0
-20.0
90
-25.0
240
120
270
150
90
240
120
150
180
180
Azimuth
60
-25.0
210
210
30
-5.0
-10.0
300
0.0
Elevation
Winegard Square Shooter VSWR
CH1
RFL
1 U FS
1_ 20.871
56.131
1
19.007 nH
470.000 000 MHz
PRm
2_ 148.3
-88.375
545 MHz
Cor
3_ 73.242
5.4102
611 MHz
3
4_ 29.746
-44.066
725 MHz
2
4
CH2
RFL
SWR
1 /
REF 1
1_: 5.655
470.000 000 MHz
PRm
2_: 4.1132
545 MHz
Cor
3_: 1.4798
611 MHz
1
4_: 3.276
725 MHz
3:1
2
4
START 470.000 000 MHz
3
STOP 806.000 000 MHz
Planning Factor Review
Gain Comparisons
Gains
dBd
20
10
0
-10
2
8
14
20
26
32
38
44
50
56
Channel
Zenith Silver Sensor
RCA ANT3023 Yagi
TERK HDTV Indoor
WineGard
RCA Loop in one direction
Channel Master
RCA Loop on the peak
Planning Factor for UHF: 10 dBd
62
68
Front to Back Ratio
>
>
>
>
>
Planning Factor: -14 dB
Loop: N/A
Indoor LP: -10 dB to -15 dB
Outdoor Dipole Array: -17 dB to -25 dB
Custom Array: -12 dB to -15 dB
What About Using Vertical
Polarization?
> Average V-Pol/H-Pol Ratios
> Zenith:
> Channel Master:
> Radio Shack 1864:
-20 dB
-19 dB
- 5 dB
Summary
> Indoor Antennas typically have lower gain than
planning factor
> Use of vertical polarization is questionable
when using linear array, higher gain receive
antennas
> Reduction of multipath reception dependent on
antenna design