There has been a significant proliferation of cellular communication towers worldwide. These towers are sited virtually everywhere that the demand for cellular communication is significant enough to justify their construction. These towers are very expensive to build.
At the same time that the proliferation of cellular communication towers has occurred, significant advances have been made in the design of wind turbines; fixed towers that have a turbine generator mounted on them that is powered by large rotating blades that are driven or propelled by the wind.
The amount of electricity that a wind turbine can generate is measured in kilowatt hours (kwH). The cost of generating electricity per kwH using wind turbines has declined significantly in recent years from approximately $0.30/kWh in 1981 to approximately $0.05–$0.08/Kwh. This decline in costs has led to the construction of large-scale developments of aggregates of wind turbines—called wind farms.
In Kansas, the Gray County Wind Farm recently became operational. It is the largest wind project in the U.S. not mandated by a state regulatory commission as part of a utility company's energy mix—which is reflective of changing cost structure of wind turbine construction. The farm consists of 170 turbines with a combined generation capacity of 110 megawatts. Compared to the emissions from 110 megawatts of coal-fired generation, the Gray County Wind Farm reduces carbon dioxide (CO2) emissions by 600 tons annually. This is the CO2 emission absorption equivalent of having a 120 square mile forest on the southwest Kansas plains.
Wind turbines function most efficiently where the wind resources are strong enough to allow for the consistent generation of electricity. A major drawback to utilizing wind turbines as cellular communications towers is that it is perceived that wind resources sufficient to power a wind turbine are generally not located in areas where cell coverage is needed—in and near large urban areas. I make three points in response to this:
First, wind turbines are quite tall; the turbine towers in the Gray County Wind Farm are 217 feet high at the hub. Towers are available from manufacturers which stand in excess of 300 feet at the hub. At these heights, wind resources are typically much stronger then at surface level. This means that the wind resources required to operate wind turbines successfully cover a much larger area—including many urban locations—than would be anticipated if wind resources were measured at surface level.
Secondly, the ability to combine two types of towers, a wind turbine tower and a communications tower, into one structure will have a positive impact upon the economics of tower construction. This will mean, ultimately, that the minimum wind resources required to make wind turbines economically viable will be lower or weaker relative to the minimum wind resources required for the viability of a stand-alone wind turbine, from a cost justification standpoint
Finally, there is a push to develop wind turbines that operate at relatively low speeds. This type of turbine technology, called low speed wind technology, is focusing on improvements required in three areas:                1. Turbine rotor diameters must be larger to harvest the lower energy winds from a larger inflow area without increasing the cost of the rotor.        2. Towers must be taller to take advantage of the increasing wind speed at greater heights.        3. Generation equipment and power electronics must be more efficient to accommodate sustained light wind operation at lower power levels without increasing electrical system costs.        
Building a stand-alone tower of either of the two types of towers discussed—a cellular communications tower or a wind turbine tower—is very expensive. Accordingly there has been a continuing search to reduce the costs of building these towers.
The present invention proposes the development of a dual-purpose structure to be used as a cellular communications tower and as a tower that would contain a wind turbine for electrical power generation. Primarily, the present invention proposes that the basic wind turbine structure will remain dominant or relatively unchanged in design. The features that modify the wind turbine structure so that it obtains communications functionality will be attached, possibly as an optional “kit” or “add-on” feature; or result in relatively minimal changes to the overall operation or construction of the wind turbine tower.
The advantage of this configuration is, primarily, that one tower can be built that will have a dual purpose—instead of two towers. This would result in significant savings in costs. In addition, these combined towers may be located in sites that are designated for cell towers—siting expenses could be saved.
It is noted here that the focus of the discussion of the present invention relates to cellular signal transmission and reception. However, it is noted that the present invention may be utilized for other types of signal transmission and reception including, but not limited to, television, radio and short wave signal transmission and reception (or a combination of different types of signals).
Although I have seen no prior art with respect to the specifics of the present invention as discussed in detail below, the general concept for combining wind turbine towers and cellular antenna is known. The following web links discuss this:    http://www.tva.gov/grreenpowerswitch/wind_faq.htm,    http://www.cetsolar.com/airindustrial.htm,    http://planning.org/zoningnews/askauthor0303.htm.
I respectfully disclose that I have not seen or heard of any other prior art with respect to the specifics of my invention.