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Rensselaer County Radio System Propagation Predictions
Rensselaer County Radio System
Rensselaer County, NY
Engineering
September 13, 2019
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
Engineering 2 Blue Wing Services
Table of Contents
1 Introduction .......................................................................................................................................... 5
2 Audio Test Data .................................................................................................................................... 6
2.1 Area 1 - Hoosick/Route 7 ......................................................................................................... 6
2.2 Area 2 - Nassau Village ........................................................................................................... 7
2.3 Area 3 - Berkshire Spur ........................................................................................................... 7
2.4 Area 4 - North Greenbush........................................................................................................ 8
3 Drive Test Data ..................................................................................................................................... 9
3.1 Frequencies Tested ................................................................................................................. 9
3.2 Sites and Parameters .............................................................................................................. 9
3.3 Drive Test Results .................................................................................................................. 11
4 Propagation Predictions ................................................................................................................... 19
4.1 Sites and Parameters ............................................................................................................ 19
4.2 Motorola Test Results versus EDX Coverage Prediction ...................................................... 21
4.3 Propagation Prediction Maps ................................................................................................. 27
5 Antenna Adjustments ........................................................................................................................ 29
5.1 Propagation Prediction Maps ................................................................................................. 29
5.2 Propagation Comparison ....................................................................................................... 31
5.3 Portable Coverage Area Comparison .................................................................................... 32
6 Conclusion and Recommendations ................................................................................................. 37
List of Figures
Figure 3-1: Eagle Bridge CH 3 - RSSI ...................................................................................................... 12
Figure 3-2: Eagle Bridge Ch 3 - RSSI Area 1 - Hoosick/Route 7 .......................................................... 13
Figure 3-3: Main Simulcast Ch 4 - RSSI .................................................................................................. 14
Figure 3-4: Main Simulcast Ch 4 - RSSI Area 1 - Hoosick/Route 7 ...................................................... 15
Figure 3-5: Main Simulcast Ch 4 – RSSI - Area 2 - Nassau Village Area ............................................. 16
Figure 3-6: Main Simulcast Ch 4 – RSSI - Area 3 - Berkshire Spur ...................................................... 17
Figure 3-7: Main Simulcast Ch 4 - RSSI Area 4 - North Greenbush Area ............................................ 18
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 4-1: Motorola Portable Audio Talk Out Test Results ................................................................ 23
Figure 4-2: EDX Coverage Prediction Method 1 .................................................................................... 25
Figure 4-3: EDX Coverage Prediction Method 2 .................................................................................... 26
Figure 4-4: Mobile Talk Out Coverage .................................................................................................... 27
Figure 4-5: Portable Talk Out Coverage ................................................................................................. 28
Figure 5-1: Adjusted Mobile Talk Out Coverage .................................................................................... 30
Figure 5-2: Adjusted Portable Talk Out Coverage ................................................................................. 31
Figure 5-3: Area 1 - Hoosick/Route 7 Present Portable Talk Out ......................................................... 33
Figure 5-4: Area 1 - Hoosick/Route 7 Adjusted Portable Talk Out ....................................................... 33
Figure 5-5: Area 2 - Nassau Area, Present Portable Talk Out .............................................................. 34
Figure 5-6: Area 2 - Nassau Area, Adjusted Portable Talk Out ............................................................ 34
Figure 5-7: Area 3 - Berkshire Spur, Present Portable Talk Out .......................................................... 35
Figure 5-8: Area 3 - Berkshire Spur, Adjusted Portable Talk Out ........................................................ 35
Figure 5-9: Area 4 - North Greenbush Present Portable Talk Out........................................................ 36
Figure 5-10: Area 4 - North Greenbush Adjusted Portable Talk Out ................................................... 36
Figure 6-1: Mobile Radio Antenna - 3 dB ............................................................................................... 38
Figure 6-2: Mobile Radio Antenna - 3 dB Elevated Feed ..................................................................... 39
List of Tables
Table 2-1: Area 1 - Hoosick/Route 7 ......................................................................................................... 6
Table 2-2: Area 2 - Nassau ........................................................................................................................ 7
Table 2-3: Area 3 - Berkshire Spur ........................................................................................................... 7
Table 2-4: Area 4 - North Greenbush ....................................................................................................... 8
Table 3-1: Drive Test Frequencies ............................................................................................................ 9
Table 3-2: Eagle Bridge Parameters .......................................................................................................... 9
Table 3-3: County Simulcast System Site Locations ............................................................................ 10
Table 3-4: County Simulcast System Site Parameters .......................................................................... 10
Table 4-1: Major Propagation Parameters .............................................................................................. 20
Table 4-2: Coverage Percentage Based on Method 1 ........................................................................... 22
Table 4-3: Coverage Percentage Based on Method 2 ........................................................................... 22
Table 4-4: Motorola Coverage Percentage ............................................................................................. 22
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Table 5-1: County Simulcast System Site Parameters .......................................................................... 29
Table 5-2: Coverage Comparison ............................................................................................................ 32
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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1 Introduction
Rensselaer County's new P25 public safety radio system provides very good mobile coverage throughout the County and meets the contract requirements of 95% portable on-street coverage. This conclusion is substantiated by the coverage acceptance test plan that was performed by the County's radio system vendor, Motorola. The results of the coverage testing showed that the coverage exceeded the contractual requirement of 95%, from both the perspective of radio signal and audio quality.
However, after a year of use, a number of areas have been identified that still may require additional coverage. The County currently has identified four (4) areas in which they desire to have the coverage reviewed.
After the review of the coverage, site parameters were reviewed to determine if any changes in site transmit power or antenna configuration could improve the areas lacking in coverage. Further, additional candidate sites where reviewed to determine if currently used sites for microwave could improve coverage, specifically the Public Safety Building in Troy.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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2 Audio Test Data
Blue Wing completed audio two-way tests to measure audio quality in the areas of poor signal coverage and reportedly problematic coverage. The following are the results of the test and confirm areas of weak portable coverage. The areas of weak coverage tend to be fairly isolated and are generally still useable for mobile communications.
2.1 Area 1 - Hoosick/Route 7
Date Location CH4 RSSI Level
CH3 RSSI Level
DAQ Score (DAQ1 - DAQ5)
Scored By (CS or Portable)
7/16/2019 Hoosick Cumberland Farms -100 -94 4.5 M. Hoppe
7/16/2019 3rd St and Rt67 -100 -102 4.5 M. Hoppe
7/16/2019 Hoosick Area Bowling -91 -105 4.0 M. Hoppe
7/16/2019 Rt67 & Rt7 -96 -101 3.4 M. Hoppe
7/16/2019 Rt7 & Rt22 Stewart’s -108 -113 1.5 M. Hoppe
7/16/2019 Rt 7 Parking area down the street from Stewart’s
-114 -123 3.4 M. Hoppe
7/16/2019 Man of Kent Tavern on Rt7 -98 -116 4.0 M. Hoppe
7/16/2019 4271 Rt 7 residence -85 -120 4.0 M. Hoppe
7/16/2019 Rt7 & Lebarron Rd -85 -130 4.5 M. Hoppe
7/16/2019 Rt7 Hobson’s Choice Greenhouse
-94 -100 4.5 M. Hoppe
7/16/2019 Rt7 Sunnyside Up Farm -97 -100 4.0 M. Hoppe
7/16/2019 Rt7 Hoosick Valley Outdoor Products
-94 -91 3.4 M. Hoppe
7/16/2019 Rt7 Creative Custom Woodworking
-96 -94 4.0 M. Hoppe
7/16/2019 Hossick Falls FD -93 -105 4.0 M. Hoppe
7/16/2019 Hoosick Falls TOPS Grocery Store
-95 -106 4.5 M. Hoppe
7/16/2019 Hoosick Falls Family Resource Center
-92 -97 4.5 M. Hoppe
7/16/2019 Hoosick FD -96 -95 4.5 M. Hoppe
Table 2-1: Area 1 - Hoosick/Route 7
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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2.2 Area 2 - Nassau Village
Date Location CH 4 RSSI Level
CH 3 RSSI Level
DAQ Score (DAQ1 - DAQ5)
Scored By (CS or Portable)
7/16/2019 North edge of village -110 -129 2.0 M. Hoppe
7/16/2019 Rosecrans St & Columbia Ave -106 -129 2.0 M. Hoppe
7/16/2019 Rensselaer St and Lake Shore St
-92 -131 3.4 M. Hoppe
7/16/2019 Elm St and Kathleen St -111 -127 2.0 M. Hoppe
7/16/2019 Nassau FD -108 -130 3.0 M. Hoppe
7/16/2019 Rt90 and Berkshire Rd -95 -129 4.0 M. Hoppe
Table 2-2: Area 2 - Nassau
2.3 Area 3 - Berkshire Spur
Date Location CH 4 RSSI Level
CH 4 RSSI Level
DAQ Score (DAQ1 - DAQ5)
Scored By (CS or Portable)
7/16/2019 Rt90 & Rt203 -115 -130 1.0 M. Hoppe
7/16/2019 Rt 90 & Bunker Hill Rd -100 -129 2.5 M. Hoppe
7/16/2019 Rt 90 & Woodward Rd -107 -129 2.5 M. Hoppe
7/16/2019 Rt90 & Rt9 -83 -129 4.0 M. Hoppe
7/16/2019 Rt 90 & Schodack Rd -73 -129 4.5 M. Hoppe
7/16/2019 Rd 90 & Muitzeskill Rd (Rt1) -98 -127 4.5 M. Hoppe
7/16/2019 Rt 90 & River Rd -65 -125 4.5 M. Hoppe
7/16/2019 Rt 90 & Rt 87 -78 -127 4.5 M. Hoppe
Table 2-3: Area 3 - Berkshire Spur
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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2.4 Area 4 - North Greenbush
Date Location CH 4 RSSI Level
CH 4 RSSI Level
DAQ Score (DAQ1 - DAQ5)
Scored By (CS or Portable)
7/16/2019 Rt150 & Rt66 -93 -129 5.0 M. Hoppe
7/16/2019 Main Ave & Douglas St -110 -130 2.0 M. Hoppe
7/16/2019 Main Ave and Rhodes St -114 -125 2.0 M. Hoppe
7/16/2019 Main Ave & Van Woert Court -99 -129 3.5 M. Hoppe
7/16/2019 Main Ave and Mountain View Ave
-105 -128 2.0 M. Hoppe
7/16/2019 Mountain View Fire House -95 -129 5.0 M. Hoppe
7/16/2019 Sharpe St and Woodbury Hill Rd -95 -129 4.5 M. Hoppe
7/16/2019 Lake View Ave and Main St -104 -130 4.5 M. Hoppe
7/16/2019 St Jude Catholic Church -91 -128 4.0 M. Hoppe
Table 2-4: Area 4 - North Greenbush
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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3 Drive Test Data
Blue Wing completed received signal strength indication (RSSI) tests to measure signal levels in the areas of weak coverage. As with the audio coverage tests, the signal strength reading confirmed the areas of poor coverage.
Below are summaries of the identified coverage areas:
• Area 1 - Hoosick/Route 7 is most isolated and caused by a topographic depression.
• Areas 2, 3 - The lack of coverage is more widespread with the area in Nassau and the Berkshire Spur.
• Area 4 - North Greenbush coverage issues are mainly located on about a 2 mile stretch in the heart of town. In addition, coverage is also marginal in areas just south of town.
3.1 Frequencies Tested
The tested 800 MHz frequencies are shown in Table 3-1.
Channel # Frequency (MHz) Site
3 854.6125 Eagle Bridge ASR Site, P25 control channel
4 858.9625 County Simulcast System, P25 control channel
Table 3-1: Drive Test Frequencies
3.2 Sites and Parameters
Site parameters for Eagle Bridge are from Motorola and coordinates from license WQYY310. The parameters for Eagle Bridge are provided in Table 3-2. Site parameters for the County simulcast system are from Motorola and coordinates from Pathfinders and license WQWR282. The parameters are given in Table 3-3 and Table 3-4.
Site Latitude Longitude Antenna Antenna Hgt. (m)
Azimuth (deg)
ERP (w)
Eagle Bridge 42-57-21.5 N 073-23-20.0 W WPA-700120-4CF-EDIN-6-850 29 110 355
Table 3-2: Eagle Bridge Parameters
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Table 3-3 identifies the site locations for the County’s main simulcast cell, which covers the vast majority of the service area.
Site City/Town Latitude Longitude Coordinate Source
Bald Mountain Brunswick 42-47-07.7 N 73-37-44.3 W Pathfinders
Buck Mountain Berlin 42-39-08.4 N 73-23-37.9 W Pathfinders
Grafton Grafton 42-44-44.6 N 73-26-45.6 W Pathfinders
LeBarron Hoosick 42-51-27.8 N 73-23-22.7 W Pathfinders
Petersburg Petersburg 42-44-23.6 N 73-19-39.4 W Pathfinders
Ridge Road East Greenbush
42-36-01.6 N 73-43-59.5 W Pathfinders
Schodack Schodack 42-33-30.9 N 73-40-24.5 W Pathfinders
Tinley Road Stephentown 42-33-26.3 N 73-26-39.6 W Pathfinders
Tsatsawassa Nassau 42-29-40.4 N 73-30-47.7 W WQWR282
Table 3-3: County Simulcast System Site Locations
Table 3-4 identifies the antenna system details in use for each site in the main simulcast cell.
Site Antenna Height (m)
Antenna Azimuth (Deg.)
ERP (W) ERP (dBm)
Bald Mountain 84.4 SC479-HF1LDF(D04-E6085) 0 174 52.4
Buck Mountain 75 SC479-HF1LDF(D04-E6085) 0 251 54
Grafton 48.8 SC479-HF1LDF(D02-E6085) 0 251 54
LeBarron 65.5 SC479-HF1LDF(D02-E6085) 0 204 53.1
Petersburg 41.1 SC479-HF1LDF(D02-E6085) 0 251 54
Ridge Road 53.6 WPA-700120-4CF-EDIN-6 190 251 54
Schodack 35.1 SC479-HF1LDF(D02-E6085) 0 407 56.1
Tinley Road 52.1 SC479-HF1LDF(D02-E6085) 0 251 54
Tsatsawassa 36.6 WPA-700120-4CF-EDIN-6-850 5 178 52.5
Table 3-4: County Simulcast System Site Parameters
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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3.3 Drive Test Results
Using Excel, the drive test data is adjusted for 2 dB cable loss and duplicate measurement locations are eliminated. The adjusted drive data is imported into ArcMap for analysis.
The results of the drive test are shown in the Figures that follow.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 3-1: Eagle Bridge CH 3 - RSSI
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 3-2: Eagle Bridge Ch 3 - RSSI Area 1 - Hoosick/Route 7
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 3-3: Main Simulcast Ch 4 - RSSI
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 3-4: Main Simulcast Ch 4 - RSSI Area 1 - Hoosick/Route 7
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 3-5: Main Simulcast Ch 4 – RSSI - Area 2 - Nassau Village Area
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 3-6: Main Simulcast Ch 4 – RSSI - Area 3 - Berkshire Spur
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 3-7: Main Simulcast Ch 4 - RSSI Area 4 - North Greenbush Area
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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4 Propagation Predictions
Mobile and portable talk out propagation predictions are created and detailed in this Section. Predictions are adjusted to reflect predictions created by the system vendor, Motorola, and the propagation data collected. The maps were created to review the potential enhancements by ERP increase and antenna adjustments
4.1 Sites and Parameters
The site and antenna details used in the propagation predictions may be found in Section 3 of this report.
The propagation parameters for the 800 MHz P25 Phase 1 LSM radio system are given in Table 4-1.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Parameter Value
Propagation Model Longley-Rice v1.2.2
Mode Mobile
Location, Time, Situation 50%
Land Use Land Clutter TSB-88
Study Point Spacing ≈300 Feet
Technology P25 Phase 1 LSM
Capture Ratio 10 dB
TDI 66 µsec
Mobile Antenna Height 2 Meters
Mobile Antenna System Gain -1.8 dB
Portable Antenna Height 1 Meter
Portable Antenna System Gain -15.4 dB 1/4 lambda whip, hip swivel case
Delivered Audio Quality (DAQ) 3.4
Reliability 95%
Mobile/Portable Area Study Type Received power at remote (Talk Out)
Mobile/Portable Faded Signal Level Threshold (Talk Out)
-110 dBm
Reliability Margin1 5 dB
Model Adjustment Portable (Loss)2 -2 dB
Model Adjustment Mobile (Loss)3 -13 dB
Table 4-1: Major Propagation Parameters
1 For 95% reliability plus 1.5 dB uncertainty margin. 2 Model adjustment considers environmental noise, antenna system, adjustments based on empirical data, and miscellaneous adjustments. 3 Model adjustment considers environmental noise, antenna system, adjustments based on empirical data, and miscellaneous adjustments.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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4.2 Motorola Test Results versus EDX Coverage Prediction
Motorola's audio portable talk out test results are compared against EDX's portable talk out coverage prediction. Motorola's test results are compared against EDX's coverage prediction using two methodologies.
The first method is referred to as Method 1 and the steps are the following:
• Import into ArcMap EDX predicted signal levels ≥ -110 dBm.
• In ArcMap create half mile tiles that cover the County.
• Using the Spatial Join tool, join the EDX predicted signal levels to the half mile tiles. If more than one EDX signal level value falls within a half mile tile take the median value and assign it to the half mile tile.
• Within the joined shapefile determine the number of tiles containing an EDX signal level and divide that number by the total number of half mile tiles to arrive at a coverage percentage.
The second method is identical to the first method except that all EDX signal levels are imported into ArcMap, the mean value is assigned to a half mile tile if more than one EDX value falls with it, and tiles that are ≥ -110 dBm are used to determine coverage.
The second method is referred to as Method 2 and the steps are the following:
• Import into ArcMap EDX all predicted signal levels.
• In ArcMap create half mile tiles that cover the County.
• Using the Spatial Join tool, join the EDX predicted signal levels to the half mile tiles. If more than one EDX signal level value falls within a half mile tile take the mean value and assign it to the half mile tile.
• Within the joined shapefile determine the number of tiles that have a signal level ≥ -110 dBm and divide that number by the total number of half mile tiles to arrive at a coverage percentage.
The results of the coverage calculations are given in the Tables that follow.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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County EDX 3 Sec. Tiles
County Half Mile Tiles
# of Tiles ≥ -110 dBm
Coverage %
184096 2776 2768 99.71
Table 4-2: Coverage Percentage Based on Method 1
County EDX 3 Sec. Tiles
County Half Mile Tiles
# of Tiles ≥ -110 dBm
Coverage %
207004 2776 2653 95.57
Table 4-3: Coverage Percentage Based on Method 2
Motorola's test results are given in Table 4-4 and shown in Figure 4-1.
County Half Mile Tiles
Passing Tiles
Coverage %
2057 2042 99.27
Table 4-4: Motorola Coverage Percentage
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 4-1: Motorola Portable Audio Talk Out Test Results
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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EDX coverage images are shown in the Figures that follow. Red indicates tiles with a signal level < -110 dBm and green indicates signal levels ≥ -110 dBm.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 4-2: EDX Coverage Prediction Method 1
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 4-3: EDX Coverage Prediction Method 2
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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4.3 Propagation Prediction Maps
The propagation predictions are shown in the Figures that follow. Predictions are for DAQ 3.4 with 95% reliability.
For mobile coverage areas of blue show predicted coverage and areas of purple show areas of possible time domain interference (TDI).
Figure 4-4: Mobile Talk Out Coverage
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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For portable coverage areas of green show predicted coverage and areas of dark green show areas of possible time domain interference (TDI).
Figure 4-5: Portable Talk Out Coverage
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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5 Antenna Adjustments
The following adjustments were made to understand if the areas of lower signal level could be improved by greater ERP and use of omni directional antennas. Only the sites around affected areas were adjusted. The propagation maps where adjusted and the results for both mobile and portable are shown. No other propagation changes were made to the parameters.
The results of this exercise show that ERP or antenna adjustments will provide marginal benefits to coverage.
Site Antenna Height (m)
Antenna Azimuth (Deg.)
ERP (W) ERP (dBm)
Bald Mountain 84.4 SC479-HF1LDF(D04-E6085) 0 174 52.4
Buck Mountain 75 SC479-HF1LDF(D04-E6085) 0 251 54
Grafton 48.8 SC479-HF1LDF(D02-E6085) 0 400* 56
LeBarron 65.5 SC479-HF1LDF(D02-E6085) 0 400* 56
Petersburg 41.1 SC479-HF1LDF(D02-E6085) 0 251 54
Ridge Road 53.6 SC479-HF1LDF(D02-E6085)* 0* 400* 56
Schodack 35.1 SC479-HF1LDF(D02-E6085) 0 407 56.1
Tinley Road 52.1 SC479-HF1LDF(D02-E6085) 0 251 54
Tsatsawassa 36.6 WPA-700120-4CF-EDIN-6-850 5 178 52.5
Table 5-1: County Simulcast System Site Parameters
5.1 Propagation Prediction Maps
The propagation predictions are shown in the Figures that follow. Predictions are for DAQ 3.4 with 95% reliability.
For mobile coverage areas of blue show predicted coverage and areas of purple show areas of possible time domain interference (TDI).
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 5-1: Adjusted Mobile Talk Out Coverage
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 5-2: Adjusted Portable Talk Out Coverage
5.2 Propagation Comparison
A comparison of the percentage of the County covered for the present system and with the ERP and antenna adjustments is calculated. The results are given in Table 5-2.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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System Coverage (%)
Present Mobile Talk Out 89.8
Present Portable Talk Out 82.0
Adjusted Mobile Talk Out 90.3
Adjusted Portable Talk Out 83.3
Table 5-2: Coverage Comparison
5.3 Portable Coverage Area Comparison
Coverage maps for portable talk out for specific areas of the County are shown in the Figures that follow.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 5-3: Area 1 - Hoosick/Route 7 Present Portable Talk Out
Figure 5-4: Area 1 - Hoosick/Route 7 Adjusted Portable Talk Out
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Figure 5-5: Area 2 - Nassau Area, Present Portable Talk Out
Figure 5-6: Area 2 - Nassau Area, Adjusted Portable Talk Out
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 5-7: Area 3 - Berkshire Spur, Present Portable Talk Out
Figure 5-8: Area 3 - Berkshire Spur, Adjusted Portable Talk Out
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 5-9: Area 4 - North Greenbush Present Portable Talk Out
Figure 5-10: Area 4 - North Greenbush Adjusted Portable Talk Out
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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6 Conclusion and Recommendations
The testing confirmed that the four areas of marginal coverage have low coverage levels for portable communications. In addition, further analysis indicates the issues would not be solved by changes in ERP or adjustments in antennas. Blue Wing recommends that the County explore additional potential sites to solve the coverage issues.
Blue Wing recommends against trying to use Vehicular Repeaters to provide additional coverage due to the operational complications many users have experienced. Users could benefit greatest from an additional site in the Nassau/Berkshire Spur area. It would be anticipated that one site could solve both areas coverage issues.
Coverage issues may need to be addressed through the use of more than just the County's radio system. As an example, the coverage issue identified in North Greenbush can be partially solved by using coverage from the Albany County P25 radio system. However, Albany County's radio system does not provide all the necessary coverage in North Greenbush. Therefore, we recommend options be explored on methods to leverage Rensselaer County's, and Albany County's radio system coverage in North Greenbush. Options for this approach may include sharing system IDs in radios and/or the integration of an Inter Subsystem Interface (ISSI) between them.
Mobile antennas play a significant part in coverage and system performance. Blue Wing recommends the use of standard 3 dB mobile antennas, standard or elevated feed, such as the ones shown in Figure 6-1 and Figure 6-2.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 6-1: Mobile Radio Antenna - 3 dB
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Figure 6-2: Mobile Radio Antenna - 3 dB Elevated Feed
Further, Blue Wing recommends performing inspections of mobile installations, and alignment checks on all radios. Motorola recommends conducting preventative maintenance inspections and tests on all their mobile and portable radios. At the very least, a quality sampling of radios should be performed to ensure reliable operation and optimal performance.
Finally, coverage in the northern portion of the County is dependent upon the proper roaming from the main simulcast cell to the Eagle Bridge ASR site. Blue Wing recommends a review of system management tools to verify this roaming is performing as intended. We also recommend performing field tests to confirm roaming and handoff from the simulcast cell to Eagle Bridge.
Rensselaer County, NY Rensselaer County Radio System Propagation Predictions Rensselaer County Radio System
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Recommended