Private/Community Wind Turbine Cellular

(Introduction - Part 1)

The Problem

Many communities and areas often find mobile-phone service to be limited in options and availability. One can look at coverage maps of the many cell-phone service providers to see that there are large areas of the United States, that include many businesses, campuses etc. where cell-phone service is not available, or very weak.

Even in cities where services are generally available coverage can be rather poor, especially in buildings, and even outdoors capacity often can be very limited and shared with a multitude of users and different applications

In many locations there can be disruptions (natural or otherwise) to all services, including power and cellular service during which the loads on everything remaining increase dramatically and make many things no longer usable. This is annoying to all but unacceptable to many authorities, enterprises that need these mission critical functions to always be available, and reliable, even more so during these unforeseen circumstances

The Solution

A combination of wind to generate clean (i.e., no carbon emissions) energy for reliable power along with dedicated private 5G cellular services. Wind turbines are a common occurrence now, very well proven and quick and easy to install and using these same facilities to also provide private 5G enhanced services is a perfect combination

Private 5G allows enterprises to have dedicated cellular resources based on the latest standards to support demanding use cases with lower latency, higher capacity, and increased bandwidth. Private 5G enables:

• Separation from public network

• Fine‑grained, predictable QoS

• Spectrum protected from wireless interference

• SIM‑based device identity and security

• Ability to cover larger areas than Wi‑Fi

• Support for high mobility

A primary omni-directional radio frequency (RF) antenna for receiving and transmitting cellular communication is mounted on each blade of a wind turbine which may be between 10 and 30 meters in height. Each RF antenna has a wired connection that passes through the turbine blade to the connection with the main shaft. At the blade’s connection with the main shaft the wired connection is attached to a slip ring which, in turn is connected to a radio unit. Being omni directional as the wind turbine rotates with, and to match, the wind direction there will be no impact on cellular coverage.

The primary RF antenna is integrated within the turbine blade, ideally internally. In the smaller turbine blades where the turbine blade would not support mounting internally the antenna may be integrated with the turbine blade material. The antenna is not exposed at the surface; at least some of the turbine blade material will cover the antenna and will conform to the available space and shape of the turbine blade into which it is integrated. Irrespective of the manner in which the antenna is integrated it will not have any effect on the aerodynamics or efficiency of the turbine blades or their operation as part of the wind turbine.

The primary RF antennas use the lower of frequency bands available with highest power and reliability to enable the widest area of service. The same antennas can be used with higher frequency bands also where possible, or these bands could have more directional antennas mounted on the pole below the wind turbine head, either way using carrier aggregation to still provide wide area service but with much enhanced localized capacity and bandwidth/speeds.

While private network turbine blades may vary between 3 and 20 meters in length, the RF antenna is typically located between 1 and 3 meters from the connection to the wind turbine’s main axle and center of rotation to get best coverage and less obstructions from the mounting pole when operating. Generally large wind turbines utilize three blades as most efficient, though the design is not limited as many smaller wind turbines have 4 or more blades as they perform better in lower wind speeds, such as when not so high and more nearby obstructions such as building and trees

Cellular frequencies of operation (in USA) – many pros and cons for all:

• Licensed mid band (2 to 3GHz) leased from an MNO in a specific area

• CBRS 3.5GHz shared band (GAA or PAL), variable service as governed by SAS

• Unlicensed 5/6GHz for NRU, shared with Wi-Fi etc. QoS is best effort

• New bands in 4/7/8GHz will probably have portions as shared spectrum

By far the best is a combination of 2 or more bands with carrier aggregation for the widest range along with highest capacity and best user experience. Multi band solution with higher band sectored antennas below the nacelle is the preferred solution. Having 2 sectored mid band (2 to 7GHz) antennas per 120 degree area with maybe 2 to 3m separation will have higher gain than omni antennas on the blades but with higher propagation losses real coverage will be less. But these higher bands would be used with carrier aggregation to just supplement the overall omni coverage nearer the tower with better performance with higher bandwidth, but further out will revert to just the low band service.

In addition with the blades spinning they will give less consistent service for low band frequencies, when a blade is in front of an antenna service in that band might not even be possible, or least restricted so will then just rely on the blade low band service. In extremes when there is no wind and the blades are stationary if they happen to be in front of some antennas these might be effectively unavailable, services will be maintained but lower bandwidth in a certain direction for some time

The effective coverage area, or range, of a typical private wind turbine cellular site can vary a lot, but is really down to these 4 key factors:

· Frequency band of operation, higher frequencies don’t go as far due to atmospheric limitations

· Height, both of the antenna above the ground but also where the tower is located

· Effective power of radio units, this is usually governed by regulatory requirement to allow coordinated sharing and coexistence of service providers, and I might also include the effective gain of antennas

· Quality of service (QoS) required, as simple measures the desired signal strength or data throughput criteria, the higher of either effectively gives a smaller range

In summary using a mid-band frequency with full power available on a normal site but some elevation over nearby terrain it can give very good QoS service for over 10 miles. In comparison using the higher frequency bands with lower power within a community so not elevated the range might be less than a mile as long as there isn’t much local clutter which can include buildings or trees

Patent pending - 63/716,476

Based in Arizona USA, for more information contact via info@microcellularsystems.com