The WMP evaluates wireless coverage throughout the nine study areas by:
•
Identifying, assessing, cataloguing and mapping exiting transmission equipment; and
•
Designing an engineered search radii template and applying it over the jurisdictional boundary of the City and County to evaluate theoretical build-out conditions; and
•
Forecasting future infrastructure needs based on the status of the existing deployments’ population trends and gaps in network coverage.
(Ord. 4703, 6-1-16)
Prior to the granting of the cellular licenses in 1980 for the first phase of deployment, the United States was divided into 51 regions by Rand McNally and Company. These regions are described as Metropolitan Trading Areas (MTA). The spectrum auction conducted by the Federal Government for the 1,900 MHz bands for 2G (PCS) further divided the United States into 493 geographic areas called Basic Trading Areas (BTA). Mesa County (including all incorporated and unincorporated areas) is located in the “Denver” MTA (a.k.a. MTA 22) and the “Grand Junction, CO” BTA (a.k.a. BTA 168). Service providers acquire the rights to deploy their networks by service area and range of spectrum frequency.
Per Section 704 of the Telecommunications Act of 1996, all service providers will require uninterrupted and continuous handoff service throughout the City and County. There are 11 known service providers that will each want to compete for the subscriber base in and around the City of Grand Junction and Mesa County. Each of these wireless voice and data providers will need towers and/or elevated antenna mounting locations to improve network coverage and capacity that will result in an ongoing need to deploy more infrastructure, especially in areas of greater residential density.
The following service providers have purchased licenses to serve all incorporated and unincorporated areas of Mesa County in the lower frequency ranges of 700 – 900 MHz: AT&T; Access 700, LLC, Dish, T-Mobile, Union Telephone (Union Cellular) and Verizon Wireless. Personal Communications Services (PCS) licensees and service providers for wireless phone and broadband operating in the higher frequencies of 1,700 – 2,700 MHz bands include: AT&T Wireless, Atlantic Wireless, Cleartalk, Clearwire Spectrum Holdings III, LLC, Commnet Wireless, LLC, Leaco Rural Telephone Cooperative, Inc., Sprint, T-Mobile and Verizon Wireless.
Most network service providers do not own the antenna mounting structure on which they attach their equipment. Tower companies typically construct and own the monopole, lattice or guyed towers and lease space on the towers to service providers. A service provider may also contract with a tower builder to construct a tower in a particular location and once the facility is constructed lease space on the newly constructed tower from the tower owner. Throughout Mesa County there are a number of tower companies who own and lease their vertical real estate to the service providers including American Tower Corporation (ATC), Crown Castle International (CCI), The Leasing Company, SBA and others.
(Ord. 4703, 6-1-16)
(a) 
Tasks A and B of the scope of services include research to gather antenna and tower location data in order to develop initial transmission equipment location base maps. The City and County GIS Departments provided some existing facility locations to CityScape. Additional infrastructure locations were obtained by CityScape from tower owners and various databases including the FCC’s database. Once the sites were mapped, each site was individually assessed and validated for:
(1) 
Physical location of existing telecommunications facilities currently within the defined study areas;
(2) 
Type of infrastructure;
(3) 
Ownership of the infrastructure; and
(4) 
Potential for future provider equipment co-location on the existing structures.
(b) 
The assessment included an in-person visit to each of the transmission equipment locations. While there are many types of antennas used for a variety of communication purposes throughout the defined study areas (dispatch, wifi hot spots, broadcast etc.), CityScape generally only included infrastructure sites in the inventory that met the following criteria:
(1) 
Towers and base stations that currently support wireless and/or cell coverage and broadband infrastructure as referenced in the EDP;
(i) 
Personal wireless service facilities (PWSF) meaning any staffed or unstaffed location for the transmission and/or reception of radio frequency signals or other wireless communications, including commercial mobile services, unlicensed wireless services, wireless broadband services, and common carrier wireless exchange access services as defined in the Telecommunications Act of 1996, and usually consisting of an antenna or group of antennas, transmission cables, feed lines, equipment cabinets or shelters, and may include a tower. The following developments shall be deemed a PWSF: new, replacement, or existing towers, public towers, replacement towers, co-location on existing towers, base station attached concealed and nonconcealed antenna, concealed towers, and nonconcealed towers (monopoles, lattice and guyed);
(2) 
Towers and base stations with microwave dish antenna because of their potential to promote co-location;
(3) 
Broadcast towers because of their potential to promote co-location; and
(4) 
Towers in remote locations because of their potential to either promote co-location or to be reconstructed to accommodate future co-locations.
(c) 
The wireless infrastructure assessment identified 142 existing transmission equipment sites that meet the prescribed criteria within the nine study areas. Also included in the assessment are 10 sites within a 1.5 mile perimeter of the County boundary. These locations were included because their signals may affect service within the defined study area. Fifteen sites contain multiple towers so the number of towers exceeds the total number of sites.
(d) 
Table 2 provides a summary of the total number of types of antenna mounting structures found throughout the study areas and Table 3 identifies the ownership of the infrastructure as of January 2016.
Table 2: Type of Infrastructure Summary
TYPE OF INFRASTRUCTURE
TOTAL
Lattice Tower
69
Guyed Tower (includes 2 guyed monopoles)
47
Base Station (rooftop or water tank)
16
Monopole Tower
14
Concealed
6
Self Support
5
Wood Pole
4
Approved But Not Constructed
4
TOTAL
165
Table 3: Owner of Infrastructure
INFRASTRUCTURE OWNER
TOTAL
Others (independent tower owners and/or local businesses)
46
Other Government Agencies (City, County, State, BLM, DOI)
17
Broadcast Companies
20
SBA
19
Unknown
19
American Tower Corporation
7
Crown Castle International
5
Verizon Wireless
5
The Leasing Company
3
AT&T
2
TOTAL
142
(Ord. 4703, 6-1-16)
Wireless location search rings are usually calculated to be circles approximately one-quarter of the radius of the proposed cell. In practice it is fairly simple to determine whether the calculated search ring radius is reasonable. The distance from the closest existing site is determined then halved and a handoff overlap of about 20 percent is added. One fourth of this distance is the search ring radius. Generally, in areas where signal coverage is the objective, taller towers allow the antenna to service a larger geographic coverage area and provide more potential for equipment co-locations by other service providers. Shorter tower heights limit the geographic coverage area and reduce the number of possible co-locations resulting in a greater number of towers required within each search ring.
The search area or search ring for new wireless infrastructure is part of a package provided to a site search consultant who looks for property that can be leased to accommodate the required wireless antenna and related infrastructure, whether that be a new tower, a rooftop or other existing structure. From an engineering perspective, any location within the search ring is considered to be acceptable to the provider after considerations are made for terrain and sometimes population distribution. The relative location of the selected property to the ideal location within the search ring will dictate the required antenna height.
(Ord. 4703, 6-1-16)
Search ring calculations for the low and high band frequencies are shown in Tables 4 and 5. The tables utilize the “Okumura-Hata” propagation path loss formula for low band, and the “COST-231” formula for high band. Maximum coverage radii for typical in-vehicle coverage is calculated for various tower heights, reduced by 20 percent to account for a reasonable handoff zone, then divided by four to obtain a search ring radius for each tower height. For example, according to the information in the following tables, a low band antenna mounted at the 100-foot elevation would have a search ring radius of 0.72 miles, and a radius of 0.36 miles for high band antennas.
Table 4: Okumura-Hata Coverage Predictions for 700 – 900 MHz
ANTENNA MOUNTING HEIGHT
50'
100'
115'
150'
Radius, miles
2.53
3.6
3.88
3.91
Allow for handoff
2.03
2.88
3.1
3.6
Search ring, miles
0.51
0.72
0.78
0.9
Table 5: COST 231 Coverage Predictions for 1,700 – 2,100 MHz
ANTENNA MOUNTING HEIGHT
50'
100'
115'
150'
Radius, miles
1.33
1.82
1.95
2.32
Allow for handoff
1.07
1.46
1.56
1.79
Search ring, miles
0.27
0.36
0.39
0.45
Tables 4 and 5 represent theoretical predictions and each facility will vary somewhat from these estimates.
(Ord. 4703, 6-1-16)
Taller structures (towers, rooftops, and water tanks) may offer more opportunity for co-location which could theoretically decrease the number of additional towers and antennas required in an area, but capacity issues may overcome the advantage of the taller structure. Each potential structure must be subjected to a radio frequency (RF) engineering review to determine the extent to which height will increase co-location opportunities. In geographic areas where there is a large wireless phone subscriber base or terrain concerns, build-out plans may require lower antenna mounting elevations. Antennas located at higher points on the support facility are more common in rural areas. In some cases, wireless providers limit the antenna placement height in more populous geographic areas because they need multiple antennas installed at differing heights on a single tower to target specific locations or to reduce the potential for interference with other equipment on the structure.
CityScape is often asked to estimate how many towers and base stations it will take to cover a particular geographic area. Because of the number of factors that might affect the coverage for a given service provider, CityScape uses theoretical root mean square (RMS) maps to help the client visualize the number of antenna locations that may be necessary to provide wireless communications coverage for a given geographic study area. This hypothetical network identifies the minimum number of tower or base station locations required for one service provider to provide complete coverage without any considerations for terrain, vegetative cover or subscriber base.
One of the key variables affecting the theoretical coverage analysis is the assumed height of the antenna on the tower or structure. CityScape reviewed the existing tower inventory and applicable height regulations for the City and County and determined the average tower height of the towers used for wireless telecommunications purposes to be around 118 feet. Therefore, the antenna mounting elevation of 118 feet was chosen for the development of the theoretical RMS coverage maps.
According to the Okumura-Hata propagation path loss formula coverage for low frequency (i.e, 800 MHz), a reasonable coverage area for an antenna mounted for cellular deployment at 118 feet on flat terrain is about 3.88 miles from the antenna. Referring to the “COST-231” formula for 1,900 MHz a reasonable coverage area for an antenna mounted at 118 feet for a high band site on flat terrain is approximately 1.95 miles. The coverage reduction from 3.88 miles to 1.95 miles reflects the variable change from low to high band frequency.
Figures containing the theoretical maps for both low and high band frequencies, for each study area, can be found in Article III of this chapter, Study Areas.
(Ord. 4703, 6-1-16)
Mapping the existing antenna sites creates a base map from which observations and analysis can be derived relative to current and future deployment patterns. Generally, most of the wireless infrastructure in Mesa County is located within and around the more urban study areas, particularly the City of Grand Junction, Lower Valley, Palisade, DeBeque and the I-70 corridor. Whitewater is the only rural study area with a larger concentration of infrastructure because of the Highway 50 corridor and the larger subscriber base in that area. Minimal or no wireless network coverage was found for the undeveloped areas within the County’s zoning jurisdiction.
Maps of the existing and proposed tower infrastructure and a site data table are provided in Article III of this chapter, Study Areas, for each individual study area. A complete listing including photographs of the verified infrastructure is provided in the January 16, 2016, inventory document.
(Ord. 4703, 6-1-16)
The next step in the network evaluation process is to examine the coverage from all known antenna locations to identify gaps in network coverage. For the purposes of this WMP, CityScape has chosen to use theoretical composite propagation modeling.
Propagation modeling is a process that uses mapping techniques to illustrate the expected level of cellular coverage theoretically provided from one or more antenna sites, based on reliable service factor most of the time. Relative signal strength is displayed in color bands to illustrate the anticipated coverage provided by each antenna. Signal strength, in this application, is a term used to approximate the level of operability and quality of service of a wireless device. The stronger the signal at the mobile device the better functionality it will have. A reduced signal lessens the quality of the call or data usage and can result in dropped calls, lack of or slow connectivity or frozen video. Distance between the mobile device and facility, intervening obstructions such as trees or buildings, and whether or not the subscriber is indoors or outside are all significant factors that affect signal strength and quality of service.
The level of propagation signal strength is shown for low band services in yellow and high band services in blue. These colors represent a generally acceptable and reliable signal level for indoor use for both low and high bands of service. Indoor usage is used as the lowest acceptable service threshold due to the signal loss that occurs from building penetration when compared to in-vehicle or outdoor pedestrian usage. Generally, the closer the mobile device is to the antenna, the more reliable and acceptable the service. The further the mobile device is from the antenna, and the closer it is to the edge of coverage, the more prone it is to service degradation when cellular usage on the tower becomes saturated or environmental conditions vary.
Theoretical composite propagation maps include terrain, vegetative cover, and current population density variables in the coverage calculations. The antenna mounting elevation is assumed to be at the highest mounting elevation of towers and base stations where the heights are known and at the average height of 118 feet for structures of unknown height. The resulting composite maps are included in the analysis provided in Article III of this chapter, Study Areas.
(Ord. 4703, 6-1-16)
Service providers use base population estimates and subscriber data to design their network, to decide how many antennas are needed and to determine how far apart antennas should be located. Depending on the number of wireless subscribers connected to a given antenna (i.e., the local wireless penetration rate) and each device’s usage, a given site has the capacity to provide service to between 1,750 and 2,500 devices. As the number of wireless devices increases and/or usage increases (particularly for more data intensive applications like social media, music and video streaming), the geographic area covered by the antenna decreases and the number of subscribers served by the facility must be reduced into order to avoid overloading the system and impacting data transfer speeds. Based on the expected increases to both subscriber rates and usage over the next 10 years, the current facility design model of 1,750 to 2,500 devices per site will shrink to between 500 to 1,200 devices per site, depending on the provider, services offered, and the number of overall subscribers. Because of this shrinkage, the number of towers and base stations needed to provide coverage to the same geographic area will increase dramatically over the 10-year period covered by this study.
The shrinkage in propagation signal pattern resulting from projected technology changes, increases in subscribers, and the usage demand caused by new applications is shown in a second set of composite maps included in Article III of this chapter, Study Areas. These maps illustrate how the network coverage patterns for a single high frequency service provider are expected to shrink over the next 10 to 15 years.
The resulting areas with no service, gaps in service, and average/acceptable service are also areas of particular planning interest in the coming years. Comparing the current coverage maps with the 10-year projection in undeveloped areas shows minimal change in future demand. However, comparing maps in more urban areas shows that coverage gaps will become larger if the network infrastructure is not expanded. The resulting geographic areas with marginal to no service are of particular planning concern over the next 10 to 15 years.
(Ord. 4703, 6-1-16)
CityScape has estimated, by study area, the number of sites that may be needed for planning purposes over the next 10 to 15 years. The estimates are based on calculations taking into account expected changes in population density, subscriber base and usage, daily transient movement through the given study area and how many calls a tower or base station may simultaneously serve at any given time. The projections include coverage, capacity, and broadband network objectives and take into account the variables of terrain, population and proposed maximum infrastructure height variables. The projection model includes all known existing antenna support structure locations (towers, rooftops, tanks and broadcast towers) for maximum co-location efficiency that reduces the number of new towers required within a given geographic area. These projection maps are also provided in Article III of this chapter, Study Areas.
While the launch date of 5G is unknown, it will happen within the next 10 years and will provide true high-speed data transfer rates in excess of today’s broadband download standard of 25 Mbps. With wireless broadband speeds available on 5G networks, most all types of communications (from voice to computer data) and entertainment (from cable/satellite TV and radio to first run motion pictures) will be available over wireless systems. Few new sites will be built to provide new coverage but to resolve over-capacity issues in an area currently served. Since 5G networks will utilize frequencies much higher than today’s 4G networks, coverage areas will be more compressed around the antenna source. Most new towers will be built to place antennas close enough to the end user to deliver the high frequency and high bandwidth speeds needed to meet broadband demands.
Construction of the new sites needed to keep up with advancing technologies and customer demand is not expected to happen evenly throughout the study area. However, over the next 10 to 15 years the cities and County should anticipate that up to 40 new tower or base station sites will be needed. The more populated areas will likely see the development of “small cell” sites. Small cells are individual “nodes” that typically consist of concealed antennas located relatively close together on shorter tower or support structures. For example, small cells can be added to existing light posts and placed every few hundred feet, or may be concealed on shorter buildings. There are many options for small cell design that allow this infrastructure to be connected to form a “mini network” that can handle the high capacity required in the more urban areas.
The cities and County can easily anticipate five to eight co-locations, upgrades or antenna modifications (in any combination) per year over the next 10 years based on expected changes in population density, subscriber base and usage, transient movement through the City and County and how many calls a tower or base station can simultaneously serve at any given time.
(Ord. 4703, 6-1-16)