Abstract:
The present invention provides systems and methods for determining positional and operating parameters of telecommunications antennae, and for improving the operation of systems of such antennae. In one aspect, the invention provides an enterprise for improving the operation of the telecommunications antennae of clients of the enterprise.

Description:
This application claims priority from U.S. patent application Ser. No. 60/783,571, filed Mar. 17, 2006. 
    
    
     TECHNICAL FIELD OF THE INVENTION  
       [0001]     This invention relates to systems for monitoring telecommunications antenna installations.  
       BACKGROUND  
       [0002]     Wireless telecommunications (“T/C”) systems are being used increasingly for both voice and data communications. There were more than 180 million cell phones users in the US in 2002, a number that has undoubtedly increased sharply since then. Cell phones are even more prevalent in many foreign countries. Other forms of wireless T/C include: microwave data and voice transmission by public utilities and private entities; short-wave communications systems between a businesses central office or dispatcher and mobile fleets of trucks, taxicabs, etc; police, fire and other public safety radio communications systems; marine short-wave radio systems; etc. With the great increase in recent years in wireless T/C systems—especially cell phones—and the vigorous competition between T/C service providers, there has been a great increase in the number of transmitting/receiving antenna installations needed. (For brevity, wireless T/C transmitting/receiving antenna installations will hereinafter generally be referred to as “T/C towers” or simply “towers”, although many such installations are mounted on buildings or other structures, especially in urban areas, rather than on free-standing tower structures.) In many cases antennae from more than one T/C service provider (hereinafter “providers” for brevity) and more than one T/C mode may be mounted on a tower.  
         [0003]     The following discussion will focus on cell phone systems and towers, since this application accounts for most of the T/C tower installations in current use. However, it will be appreciated that the matters discussed will apply equally to other T/C applications.  
         [0004]     It is estimated that there are more than 100,000 cell phone towers in the US. Cell phone service providers providing nationwide service typically divide their operations into a half-dozen or so regional offices, each of which includes a number of local offices serving either a large city and it&#39;s surrounding area, or a rural area. A large provider in a large city area will typically have 1,500 or more towers with 10,000 or more individual antennae.  
         [0005]     A typical tower will have three antennae oriented about 120° apart horizontally (i.e., azimuth) to serve three sectors of its service area, and may be aimed at an angle above or below the horizontal (“tilt”). In some installation, separate receive and transmit antennae may be employed, so there may be 3 or 5 antennae per sector. “Omnis”—omnidirectional antennae radiating equally in all horizontal directions—may also be employed.  
         [0006]     Cell phone service can be provided by any of several different T/C protocols and can use one of several wavelength bands available for cell phone service. Each cell phone mode—i.e, combination of protocol and wavelength band—will require a separate set of antennae; the multiplicity of antennae for the different cell phone modes serving a given area are typically mounted on the same tower.  
         [0007]     Each antenna may be characterized by geographic position (i.e., longitude and latitude) and height (either absolute height, relative to sea level, or height above local ground); azimuth (the angle in the horizontal plane of the antenna&#39;s radiation pattern axis to a reference direction such as true or magnetic north); tilt (the angle above or below horizontal of the antenna&#39;s radiation pattern axis); and the specific type or model of the antenna and auxiliary equipment mounted with it.  
         [0008]     Each tower will have an associated base station, which includes power supplies, radio equipment, filters, and interfaces with conventional wire, microwave link or fiber optic cable telephone transmission lines, and other accessory equipment required for the antennae on the tower.  
         [0009]     To insure proper operation of these installations, verification that antennae position and orientation as installed complies with design parameters is necessary, as is monitoring to detect variations from the design parameters caused by weather, slippage or sagging of mounting hardware, or other unanticipated effects. Visual inspection of the area covered by a given antenna, to detect trees, buildings or other objects which have appeared since the original antenna installation and which may shield or otherwise interfere with the operation of the antenna, is also desirable. And with ongoing maintenance operations which may involve replacement of older antennae at a tower, knowledge of equipment installed at a given location, date of installation, model and serial numbers, etc is necessary.  
         [0010]     Furthermore, to optimize service coverage, the location and coverage area of each tower must be reviewed frequently on both a local and regional level, to take into account planned service improvements, changing demographics, construction of new structures which may interfere with antennae operation, and installation of new towers.  
         [0011]     New developments in cell phone technology, such as the ability to alert a user of automotive service facilities, restaurants, shops etc. in his/her vicinity; the requirement that the geographical location from which 911 calls originate be accurately determined; and the increasing use of mobile signal-strength and performance monitoring equipment (“Can you hear me now?”); all put a priority on having accurate antennae location and alignment information continuously available.  
         [0012]     Verification and monitoring of antenna parameters, including geographic position and elevation, orientation, visual information, and inventory, generally requires that maintenance personnel climb towers which may be more than 100 ft. high, or gain access to installations on exposed exterior of tall buildings. Such verification is expensive, because of the time needed to gain access to the antenna, and in many cases hazardous.  
         [0013]     There is clearly a need for a system for monitoring and verifying the parameters of a very large number of individual antenna, and making information on the parameters available at the base station serving the antenna, and at the local and regional offices in whose territory the antenna is located. Because of the expense and hazard of accessing the antennae, any such system must be highly reliable, and the large number of antennae dictates a relatively low-cost system. A readout of antenna parameters should be available at the base station of the installation, and via remote transmission, at the local and regional offices of the provider. In addition, identifying information on the equipment installed in the base station should similarly be available. The present invention provides such a system.  
         [0014]     For maximum utility data from such monitoring system should be assembled and tabulated in a data base in a form readily available to the provider&#39;s engineering and maintenance personnel.  
         [0015]     Systems exist which will monitor the azimuth and tilt of an antenna, and adjust these parameters in response to remote external commands or internal, remotely adjustable, set-points. Typical of such systems are the inventions disclosed by Wesniak in U.S. Pat. No. 6,864,847 B2, and by Singer et al in U.S. Pat. No. 6,239,744 B1. Such systems are relatively expensive (compared to just monitoring the parameters), and the increased complexity may require additional maintenance. The inventions of Wesniak and of Singer et al do not provide for visual monitoring or inventory recording.  
       OBJECTIVES AND SUMMARY OF THE INVENTION  
       [0016]     It is an objective of the present invention to provide a system to monitor data relative and the inventory of base station equipment in use.  
         [0017]     It is a further objective of the present invention to provide a system to make such data available by remote connection at the base station serving the antenna, and at the local and regional offices of the provider.  
         [0018]     It is a still further objective of the present invention to provide such a system which is economical to fabricate and install and which requires minimal maintenance.  
         [0019]     It is a still further objective of the present invention to provide a method of collecting data relative to the geographic location of a T/C antenna, its elevation, the azimuthal and tilt orientation of the antenna, the visual scene “seen” by the antenna, and the inventory of the antenna and its associated equipment (the “installation data”) and providing said data to T/C service providers in a form readily useable by the provider&#39;s engineering, maintenance or other personnel.  
         [0020]     The present invention achieves these objectives by providing means for determining and reporting three-axis absolute position (i.e., latitude, longitude and elevation), tilt and azimuth of the antenna of interest, as well as a camera image of the visual field “seen” by the antenna, and the antenna and base station inventory data. The information of interest may be transmitted to the base of the antenna tower or building upon which the antenna is mounted, and/or transmitted to one or more central locations where a plurality of antennae are monitored.  
         [0021]     In another aspect of the present invention, a service is provided to T/C service providers comprising collecting three-axis absolute position (i.e., latitude, longitude and elevation), tilt and azimuth of the antenna of interest, as well as a camera image of the visual field “seen” by the antenna, and the antenna and base station inventory data, collating the information and providing it to T/C service providers in a convenient format for utilization by the provider&#39;s engineering, maintenance or other personnel. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0022]     The present invention comprises means to determine the geographic position and elevation of a T/C antenna, means to determine the azimuth of the antenna, means to determine the tilt of the antenna, means to record the visual field the antenna radiates into, means to determine and record the antenna installation data such as serial numbers or other identifying data relating to the antenna and its accessory equipment, means to determine and record identifying data relating to the equipment installed at the base station serving the antenna, and means to communicate the information collected by said means to the base station, and also to remote sites.  
         [0023]     Means to determine the geographic position of the antenna may comprise any of the GPS measuring devices known to the art. In the preferred embodiment, said means may comprise the GPS 25-LVC PhaseTrac 12 Sensor Board module with a Garmin GA 29 remote GPS antenna, both available from Garmin International Inc., 1200 E. 151st Street, Olathe, Kans. 66062-3426. For greater accuracy and precision, the preferred embodiment may also comprise a Garmin GBR 23 Differential Beacon Receiver, available from the same source. The GPS module will provide outputs of latitude, longitude and elevation accurate to about 5 meters or less. Alternatively, the vertical position of the antenna above local ground level may be determined by conventional techniques such as measurement by tape measure or transit, which may be comprised within the installation data recorded by the means to determine and record the installation data.  
         [0024]     New developments in GPS technology and other technologies relating to geographic position determination have been developed or are under development at the present time. Such advanced technological means may provide significantly more precise determination of position relative to a reference position; this technology may enable determine elevation of an antenna relative to a reference position such as the antenna&#39;s base station with an accuracy of significantly better than one meter. The present invention contemplates antennae monitoring provisions comprising such differential position-measuring technology.  
         [0025]     In an alternate embodiment, the geographic position and elevation and/or antenna height may be determined by any means known to the art, such as map coordinates and height measurement by tape measure or transit, at the time the tower is constructed or the antenna installed, and the data recorded as part of the installation data recorded by the means to determine and record the installation data.  
         [0026]     Means to determine the azimuth of the antenna may comprise any of the many angular measuring devices known to the art. In the preferred embodiment, said means may comprise the Vector 2X or 2Xe magnetic compass modules, available from PNI Corporation, 133 Aviation Blvd, Suite 101, Santa Rosa, Calif. 95403. These modules provide an output of the absolute (i.e., with respect to magnetic north) compass heading. The means to determine the azimuth would be mounted on the antenna support structure, and the azimuthal offset of the mounting with respect to the antenna&#39;s radiation pattern axis would be recorded as part of the installation data recorded by the means to determine and record installation data relating to the antenna.  
         [0027]     Means to determine the tilt of the antenna may comprise any of the many inclinometers known to the art. In the preferred embodiment, said means may comprise the EZ-TILT-2000-30 system inclinometer/tilt detector sold by AOSI of Linden, N.J. The means to determine the tilt would be mounted on the antenna support structure, and any tilt offset of the mounting with respect to the antenna&#39;s radiation pattern axis would be recorded as part of the installation data recorded by the means to determine and record installation data relating to the antenna.  
         [0028]     Means to record the visual field the antenna radiates into may comprise any of the very many remote camera systems known to the art. Requirements for such systems are modest, since the primary purpose would be to detect any object which would adversely impact the radiation and receiving pattern of the antenna. Such objects, such as foliage from nearby plants, newly erected structures, or construction cranes nearby, for example, would be essentially static or slowly moving, so that high-speed imaging would be unnecessary. Nor would high optical resolution be required, since only relatively large, nearby objects would be of interest. Imaging under daylight conditions would suffice, so that high light sensitivity would be unnecessary. Selection of an appropriate camera system would be determined by such factors as cost, durability, ease of mounting on the antenna support, etc, and one skilled in the art could readily make such selection.  
         [0029]     In the preferred embodiment, said means may comprise M/N MVC3000 Miniature Tube Camera, available from Micro Video Products, One Mill Line Road, Bobcaygeon, Ontario, Canada, K0M 1A0.  
         [0030]     Means to communicate the data relating to the installation geographic position and antenna elevation/height, data relating to the antenna&#39;s azimuthal orientation, data relating to the antenna&#39;s tilt, and installation data (see below) to the base station serving the antenna, and also to remote sites (the “data system”) may comprise any of the data logging and transmission systems well known in the art. In preferable embodiments, the data system will comprise a microprocessor to store installation data, and to control measurement and reporting sequences. In the most preferable embodiment, the data system would usually operate under its stored program, but would be controllable and programmable from the base station and the remote sites when necessary. This controllable and programmable feature would enable provider personnel to interrogate the antenna data out of sequence, and to upgrade or otherwise modify the stored program. Also, the design values of azimuth and tilt could be stored in the data system, to assist in later verification of antenna orientation by the provider&#39;s maintenance, engineering and administrative and other personnel. Transmission to the base station and remote location could be by means of wireless and/or “land line” methods.  
         [0031]     A cell phone industry group known as the Antenna Interface Standards Group (http://www.bcba15324.pwp.blueyonder.co.uk/) is currently engaged in developing communication protocol standards for use in communications between antennae and remote sites. In preferred embodiments of the present invention, means to communicate the data relating to an antenna and its auxiliary equipment will comprise facilities to conform to such standards as they become available. Incorporation of microprocessor-based means to determine and record the installation data, such as is disclosed below, will facilitate such conformance.  
         [0032]     Means to determine and record the installation data, such as serial numbers or other identifying data relating to the antenna and its accessory equipment, comprise devices and methods such as are well known in the art to facilitate capture of the installation data and its storage in local units at the antenna site and/or at remote sites. In a preferred embodiment, all of the components of an antenna installation would carry a bar code, and the technician installing the antenna would scan the bar code of each item using a hand-held scanner connected to the data system, thereby storing the installation data in the data system. The data system may comprise programmed sequences to instruct and/or remind installation personnel to scan in each needed identification datum. In the most preferred embodiment, all of the components of an antenna installation would be equipped with RFID (Radio Frequency Identification) chips; such chips are interrogated by RF transceivers, using devices and methods well-known in the art, to generate a unique electronic signature—in effect an “electronic bar code”—which identifies the chip. The most preferred embodiment of the T/C antenna monitoring system of the present invention would comprise RFID chips and suitable transceivers to uniquely identify the antenna and auxiliary components to which the chip is affixed. Each antenna, or alternatively each group of antennae mounted close together, would have a suitable transceiver.  
         [0033]     Similar techniques would be used to identify the base station equipment in use at the tower, and make such data similarly available at base station and remote locations.  
         [0034]     With the typical tower installation comprising three or more individual antennae, the antenna monitoring system of the present invention could, in alternate embodiments, comprise some components serving a single antenna and some components serving all of the provider&#39;s antennae mounted on the tower. Thus, each individual antenna would comprise means to measure azimuth, tilt and visual field, and antenna installation data would be recorded for each individual antenna, but a single common data system could serve all antennae on a tower and the equipment in the base station.  
         [0035]     The antenna validation system of the present invention could be operated in several different modes. In one mode, a maintenance technician could, in a routine maintenance inspection to a tower, verify that all antennae on the tower were properly aligned, and that no interfering objects were detected in the antennae&#39;s field. Only in the case of a departure from design parameters would the technician need to physically access the antenna and make corrections.  
         [0036]     In local and regional providers&#39; offices, data transmitted from all of the provider&#39;s antenna could conveniently be stored in a database for easy access. Provider personnel at the offices could easily search for any individual antenna in their area, and verify its installation parameters and inventory.  
         [0037]     A local office may use the data; for example, to schedule periodic maintenance and replacement of components, to plan additional tower installations to improve signal coverage, or to determine the antenna or tower involved in customer or technician reports of inadequate service or outage. Regional offices may use the data for coverage-planning purposes, for financial analysis, and for inventory control. (Accounting and auditing personnel generally do not like to climb cell phone towers.)  
         [0038]     In another aspect of the present invention, a service may be provided, as a business enterprise, comprising collecting antenna validation data—i.e., the geographic position, elevation and tilt of a T/C antenna, of the antenna, the visual field the antenna radiates into, and the antenna installation data such as serial numbers or other identifying data relating to the antenna and its accessory equipment, and identifying data relating to the equipment installed at the base station serving the antenna—for a plurality of antennae located at a plurality of locations and owned by a plurality of T/C service providers who are customers or clients of the business enterprise—collating and tabulating such data in a data base, and generating reports for each of the client T/C service providers, giving the antennae validation data of their antennae. The reports may provided either on demand from the clients or with a predetermined temporal periodicity, or when an exception, or departure from design or initial antennae parameters of more than a predetermined “allowable deviation”, is detected.  
         [0039]     In order to perform such exceptions monitoring, the monitoring system of the present system may utilize repetitive scanning of the data base of antennae validation data as a “background” task, to facilitate prompt detection of exceptions.  
         [0040]     The above disclosure described the use of the present invention in one T/C application: cellular telephony. It will be apparent to one skilled in the art that the invention is applicable to any other T/C application requiring the use of antennae which must be accurately positioned and aimed, and the present invention contemplates the use in such other applications.  
         [0041]     Other embodiments will be apparent to one skilled in the art, which will change various details of the present invention without limiting its scope. Furthermore, the foregoing description of the preferred embodiment of the invention and the best mode for practicing the invention are provided for the purpose of illustration only and not for the purpose of limitation of the invention, which will be defined by the claims appended hereto.