Abstract:
A correlated weather and communication performance measurement system includes a processing system and a communication interface. The communication interface receives performance data and weather data. The performance data indicates communication performance for a wireless communication system. The weather data indicates weather conditions for a geographic area including the wireless communication system. The processing system correlates in time the communication performance and the weather conditions for the wireless communication system, determines service levels that apply to the weather conditions, compares the service levels that apply to the weather conditions to the communication performance correlated in time to the weather conditions, and generates validation data based on the comparison to validate the service levels.

Description:
RELATED APPLICATIONS 
   This application is a continuation of prior application Ser. No. 10/233,710, filed Sep. 3, 2002, now U.S. Pat. No. 6,725,160 entitled, “Correlated Weather and Performance Measurement System for Extremely High Frequency Wireless and Free Space Optical Communication Systems,” hereby incorporated by reference into this application. 

   FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable 
   MICROFICHE APPENDIX 
   Not applicable 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention is related to the field of communications, and in particular, to a system that correlates weather and communication performance for wireless communication systems. 
   2. Description of the Prior Art 
   In the telecommunications industry, the “last mile” to the customer still forms a bottleneck that undermines the full exploitation of technologies such as the Internet. Although de-regulation was supposed to usher in new competition, large telephone and cable TV companies still control the majority of the twisted pair and coaxial cable connections to end-users. Alternative access to these end-users is needed. This alternative access should have high availability and high bandwidth. 
   Extremely high frequency wireless communication systems and free-space optical communication systems could provide the needed alternative access to these end-users. Extremely high frequency wireless communication systems transfer wireless signals over the air at frequencies above 10 gigahertz—ten billion cycles per second. Some examples of extremely high frequency wireless communication systems include multi-channel multipoint distribution systems, local multipoint distribution systems, V-band systems, and W-band systems. Free-space optical communication systems transfer wireless signals over the air at frequencies above 10 terrahertz—ten trillion cycles per second. Some examples of free-space optical communication systems include laser systems and infrared systems. Advantageously, extremely high frequency wireless communication systems and free-space optical communication systems can exhibit both high availability and high bandwidth—especially when used together in a hybrid system. 
   Unfortunately, the weather adversely affects both extremely high frequency wireless communication systems and free-space optical communication systems. Existing test systems do not obtain adequate data to properly assess comparative system performance under various weather conditions. New systems are needed to provide detailed data regarding the performance of these systems in various weather conditions. 
   SUMMARY OF THE INVENTION 
   Examples of the invention include correlated weather and communication performance measurement systems, their methods of operation, and associated software products. Some examples of the invention include a correlated weather and communication performance measurement system that includes a processing system and a communication interface. The communication interface receives performance data and weather data. The performance data indicates communication performance for a wireless communication system. The weather data indicates weather conditions for a geographic area including the wireless communication system. The processing system correlates in time the communication performance and the weather conditions for the wireless communication system. The processing system determines service levels that apply to the weather conditions. The processing system compares the service levels that apply to the weather conditions to the communication performance correlated in time to the weather conditions. The processing system generates validation data based on the comparison to validate the service levels. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  illustrates a weather and communication performance measurement system in an example of the invention. 
       FIG. 2  illustrates a computer system in an example of the invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1–2  and the following description depict specific examples to teach those skilled in the art how to make and use the best mode of the invention. For the purpose of teaching inventive principles, some conventional aspects have been simplified or omitted. Those skilled in the art will appreciate variations from these examples that fall within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. As a result, the invention is not limited to the specific examples described below, but only by the claims and their equivalents. 
     FIG. 1  illustrates weather and communication performance measurement system  100  in an example of the invention. System  100  includes communication systems  101 – 103 , performance measurement system  110 , weather measurement system  120 , data correlation system  130 , service validation system  140 , and stress introduction system  150 . Communication systems  101 – 103  communicate over respective links  104 – 106 . Based on this disclosure, those skilled in the art will appreciate how to modify and/or combine existing communications, weather, and computer equipment to make and use system  100 . 
   Communication systems  101 – 103  could be extremely high-frequency wireless communication systems and/or free space optical communication systems, and thus links  104 – 106  would be extremely high-frequency wireless communication links and/or free space optical communication links. In the context of the invention, extremely high frequency wireless communication systems transfer wireless signals over the air at frequencies above 10 gigahertz—ten billion cycles per second. Some examples of extremely high frequency wireless communication systems include multi-channel multipoint distribution systems, local multipoint distribution systems, V-band systems, and W-band systems. In the context of the invention, free-space optical communication systems transfer wireless signals over the air at frequencies above 10 terrahertz—ten trillion cycles per second. Some examples of free-space optical communication systems include laser systems and infrared systems. Advantageously, extremely high frequency wireless communication systems and free-space optical communication systems could be implemented to solve the last-mile bottleneck by providing alternative access to end-users over the air. 
   Performance measurement system  110  measures the communication performance of communication systems  101 – 103 . Communication performance includes received signal power, data rate, bit errors, link availability, packet loss, packet latency, bit error seconds, severe bit error seconds, framing errors, or some other effective communication performance measures. One example of a severe bit error second is a one second time period that has a bit error rate of 10 −3 . Performance measurement system  110  transfers performance data  111  to data correlation system  130 . Performance data  111  indicates the individual communication performance for each of communication systems  101 – 103 . In some examples, performance measurement system  110  runs the same communication performance test on the communication systems at the same time. For example, performance measurement system  110  could separately run the same bit error test at the same time on system  101  over link  104 , system  102  over link  105 , and system  103  over link  106 . Performance measurement system  110  could be physically separate from but coupled to communication systems  101 – 103  or system  110  could be partially or totally integrated within communication systems  101 – 103 . 
   Weather measurement system  120  measures the weather conditions for the geographic area including communication systems  101 – 106 . Weather measurement system  120  transfers weather data  121  to data correlation system  130 . Weather conditions include fog, precipitation rate, particulate size, visibility, wind speed, wind direction, temperature, humidity, solar conditions, sunset/sunrise conditions, and other effective atmospheric measurements. 
   Data correlation system  130  receives and processes performance data  110  and weather data  121  to generate and transfer correlated data  131  that correlates in time the communication performance and the weather conditions for each of communication systems  101 – 103 . In some examples, performance data  111  and weather data  121  are both time stamped, and data correlation system  130  correlates actual communication performance to actual weather conditions based on the time stamps. Other techniques could be used to correlate in time the actual communication performance and the actual weather conditions. 
   Service validation system  140  receives and processes correlated data  131  to compare the communication performance to a service level applicable to the weather conditions that are correlated to the communication performance. Service level validation system  140  could then transfer validation data  141  indicating if service levels are met. Service validation system  140  would determine the service level that applies based on the actual weather conditions, and then compare the actual communication performance during the actual weather conditions to the pre-determined service level for those weather conditions. 
   For example, different service levels could be specified having different minimum data rates and maximum bit error rates. These different service levels could then be associated with different ranges and combinations of weather conditions—such as precipitation rate, particulate size, temperature, and humidity. Service validation system  140  would identify the service level that is applicable to the actual weather conditions. Service validation system  140  would then compare the applicable service level to the actual communication performance—the actual minimum data rate and maximum bit error rate—that was correlated in time with the actual weather conditions. Thus, service levels for various weather conditions could be specified and validated based on actual communication performance and actual weather conditions. Service validation system  140  could be omitted in some examples of the invention. 
   Stress introduction system  150  creates artificial communication stress conditions for communication systems  101 – 103 . For example, stress introduction system  150  could comprise a clouded lens that free-space laser signal must pass through. In another example, stress introduction system  150  could generate RF interference signals across links  104 – 106 . To provide fair comparisons, stress introduction system  150  would typically introduce the same stress to each of communication systems  101 – 103  at the same time. Stress introduction system  150  could be omitted in some examples of the invention. 
   There are various implementations of system  100  that fall within the scope of the invention. There could be one communication system or numerous communication systems. The communication systems could use different technologies and/or be from different suppliers to assess comparative performance during various weather conditions. A group of communication systems from the same supplier could use communication links of different ranges to identify range limitations during various weather conditions. Groups of communication systems could be geographically separated to test communication performance under different weather conditions that are prevalent in different geographic areas. For example, groups of communication systems could be located at test sites in a snow prone area, fog prone area, heat prone area, and rain prone area. 
   System  100  could be designed to test various communication systems during various weather conditions to find optimum technologies and equipment for each of the weather conditions. In some cases, a hybrid system can be developed that combines these optimum systems, and that subsequently uses the optimum system based on the actual weather conditions in the field. 
   Instead of development testing, system  100  could be implemented to perform service validation for commercially deployed communication systems. 
     FIG. 2  illustrates computer system  200  in an example of the invention. Computer system  200  could implement performance measurement system  110 , data correlation system  130 , and/or service validation system  140 , and thus, systems  110 ,  130 , and  140  could be integrated together or have separate systems. In addition, computer system  200  could be used to control weather measurement system  120  and/or stress introduction system  150 . Computer system  200  includes communication interface  201  and processing system  202 . Processing system  202  is linked to communication interface  201  and includes storage system  203 . Storage system  203  stores control software  204 . 
   Computer system  200  could be comprised of a programmed general purpose computer, although those skilled in the art will appreciate that programmable or special purpose circuitry and equipment may be used. Computer system  200  may use a client server architecture where operations are distributed among a server system and client devices that together comprises elements  201 – 204 . 
   Communication interface  101  exchanges data  205  between processing system  202  and external systems. Data  205  that is received includes performance data and weather data. Data  205  that is transferred includes correlation data and/or validation data. Communication interface  201  could comprise a network interface card or some other communication device. Communication interface  201  may be distributed among multiple communication devices. 
   Processing system  202  could comprise a computer microprocessor, logic circuit, or some other processing device. Processing system  202  may be distributed among multiple processing devices. Storage system  203  could comprise a disk, tape, integrated circuit, server, or some other memory device. Storage system  202  may be distributed among multiple memory devices. 
   Processing system  202  retrieves and executes control software  204  from storage system  203 . Control software  204  could comprise an application program, firmware, or some other form of machine-readable processing instructions. When executed by processing system  202 , control software  204  directs processing system  202  to operate in accord with this disclosure. In particular, processing system  202  processes performance data that indicates communication performance for a plurality of communication systems and weather data that indicates weather conditions for a geographic area or areas including the communication systems to generate correlated data that correlates in time the communication performance and the weather conditions for each of the communication systems. Processing system  202  may also process the correlated data to compare the communication performance to a service level applicable to the weather conditions correlated to the communication performance. 
   The following table illustrates correlation and validation data in an example of the invention. Note that the actual table entries are left blank and would be determined based on actual measurements and field conditions. The date/time, weather data, performance data, and validation determination are listed in the left column and the communication systems are listed across the top row.  
   Note that the table could also include averages that are kept over a specified time periods. Note that numerous other graphs and data representations could be used in other examples of the invention.