Implementation Of Casa System Computer Science Essay

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

1.1 Objective

The goal of this document is to identify an urban area in US where implementation of CASA system will have a greater impact, also to provide the motivation and necessity behind the need of CASA system for the area chosen. The Urban area chosen is Indianapolis. The necessity of a CASA system for an urban area can be justified with the number of people, business and economy it affects in an event of hailstorm, thunderstorm or tornado and the frequency of these events.

1.2 Motivation

1.2.1 Indianapolis

Indianapolis, the capital of Indiana is one of the most prolific cities in the mid-western region of United States of America. Historically, Indianapolis was known for industry and climatic conditions. Indianapolis is considered as one of the best cities in the US due to the fact that it has more than 200 retail shop, 35+ hotels, museums, restaurants, theatres etc [1]. It's one of the fastest growing metropolitan cities in the US and sits tenth among US metropolitan areas for GDP growth [2]. As of 2011 census, the city's population is about 827609 [3] and is the twelfth largest city in terms of population in the US.

1.2.2 Population

The population and density of the region is given below [4]

Population City



2,273/sq miles (861/km2)

1.2.3 Economy

Indianapolis is one of the important cities with a good business infrastructure. It is the headquarters for a numerous companies like  Eli Lilly and Company,  Brightpoint, Wellpoint, Marsh Supermarkets, Finish Line, and Gregg Appliances Inc. and REIT Simon Property Group. Other important Indianapolis employers are Indiana University Health, Sallie Mae, Cook Group, Rolls-Royce, Delta Faucet Company, Ice Miller, Raytheon, Carrier and General Motors

Indianapolis is an important centre for logistics and distribution facilities. It's the distribution centre for, Foxconn, Finish Line, Inc., Fastenal, Target, and CVS Pharmacy [5].

Indianapolis is a hub for Automobile industry next to Detroit city with companies like Duesenberg, Marmon Motor Car Company, Stutz Motor Company, American Motor Car Company, Parry Auto Company,  and Premier Motor Manufacturing.

According to Forbes magazine, Indianapolis is considered as the sixth best city for jobs and ranked twelfth nationally in total home foreclosures [6] [7]. The National Association of Home Builders and Wells Fargo ranked Indianapolis in 2009 as the most affordable housing market in the US [8]. Indianapolis was ranked sixth among U.S. cities as a retirement destination in 2011 [9] and one of the best Midwestern cities for relocation [10].

1.2.4 Climate

Indianapolis has a humid continental climate with four seasons. Indianapolis has an unpredictable weather condition where the city experiences thunderstorms, floods, flash floods, hails and tornados. Most people do not consider Indianapolis as a tornado prone city but Indianapolis takes the top spot in the Midwestern region. The Indiana state is ranked sixth in the tornado prone states [11]. Frequent Thunderstorm and hails are prominent in Indianapolis. The following table explains the frequency of events [12] [13].

Climate CONDITion [12] [13]


11 events on average


12 events on average


5 events on average


1-2 events on average Thunderstorm

Indianapolis experiences about eleven severe thunderstorms every year. Due to severe thunderstorms, floods are also present leading to severe damage. The city's average annual precipitation is 41 inches [14]. Hail

Indianapolis experiences two to three activities of Hail. Hail is experienced every year consistently over the last ten years Tornado

Indianapolis is the hub for tornados in the Midwestern region. According to Forbes, Indianapolis is ranked eighth in the tornado prone cities in the US. The Marion county (Indianapolis) has had 41 tornados since 1950 [15] and May is considered as the peak tornado month. Records say that 1.7 tornados are experienced each year per 1,000 square miles [15].

1.3 Weather Radar System

// The word radar is an acronym derived from the phrase radio detection and ranging and applies to electronic equipment designed for detecting and tracking objects at considerable distances. The basic principle behind radar is simple - extremely short bursts of radio energy (traveling at the speed of light) are transmitted, re¬‚ected off a target and then returned as an echo.

Weather radar, also known as Doppler weather radar, is a type of radar which is used to determine precipitation and it's motion, and estimate its type (rain, snow, hail, etc.). The Doppler radar makes use of the Doppler effect which states that change in the apparent frequency of a wave as observer and source move toward or away from each other. Here Dual Doppler radar system is used. The dual Doppler radar is the only remote sensing instrument that can detect tracers of wind to reveal a storm's internal structure and the hazardous phenomena harbored therein. The dual Doppler weather radars has been a revelation to radar observations where information are provided to improve the estimation of rainfall and to determine the type of precipitation. The data collected can be analyzed to determine their potential to cause severe weather.

1.4 System Design

Fig 1.1 radr2.JPG

A radar system is composed of many different components and subsystems. The main subsystems are discussed. In a dual Doppler radar system, certain amount of time is used for transmission and as well as for reception. During transmission, the transmitter produces electromagnetic signal. This signal is transmitted into the medium of propagation. When the electromagnetic signal reaches hits a object, it is reflected back to the radar. This phase is the reception. The information collected by the radar system is transmitted to the Datacenter. The Datacenter is like a repository for weather information. A primary datacenter is present which is in charge of storing and distributing weather information. A secondary datacenter is also present as a backup The Datacenter and the radar system are connected by a primary network connection. A secondary network connection is also present if primary connection fails. Fig 1.2 shows the presence of Primary and Secondary Datacenter and network connection. From the Datacenter the weather information are distributed to the weather agency and the public.

Fig 1.2RADR1.JPG

1.5 Requirements of a Weather Radar System

The requirement for a weather radar system has to be meticulously constructed and structured. A lot has to be considered before a requirement is been made. Each requirement has impact on the other and is interdependent. There are three major requirement levels that have to be considered.

Stakeholder requirements

High level System requirements

Subsystem level requirements

Each requirement has numerous sub levels

1.5.1 Stakeholder Requirements

The Stakeholder requirement is the most important requirements due to the fact that based on these requirements the system level requirements are framed. The most important stakeholders are listed below:


Weather agency

Maintainer Public

To maintain the important functional capabilities of CASA system and to address the operational problems, the advantages and disadvantages of the system and their effects on public must be analyzed. It is very important to incorporate public needs at the start and end of the research and development process is crucial in attaining the most efficient system. The public are the most important stakeholders. The whole CASA system is developed solely to provide weather information to the public. The public have to be alerted about the weather information through mail, message or media. It's very important to provide accurate weather information to the public. The security has to be kept in mind and information has to be transmitted through secure protocol. Weather Agency

The official weather agency of the United States is National Oceanic and Atmospheric Administration (NOAA). It is a scientific agency within the United States Department of Commerce focused on the conditions of the oceans and the atmosphere. NOAA warns of dangerous weather, charts seas and skies, guides the use and protection of ocean and coastal resources, and conducts research to improve understanding and stewardship of the environment. NOAA with its cutting-edge research and high-tech instrumentation provides public, planners, emergency managers and other decision makers with reliable information they need when they need it. The Weather agency issues daily and monthly climate reports for weather stations within their area of responsibility. These generally include recorded highs, lows and other information. This information is considered preliminary until certified by the National Climatic Data Center.  National Climatic Data Center  is one of the largest active archive of weather data. They are responsible in alerting the users with required weather information through media, mail and messaging.

The NOAA has to be a reliable and this is accomplished with the performance of the dual Doppler radar system. The Dual Doppler radars have to be sufficient placed in order to obtain accurate measurement. The Weather agency has to be secured and must be made sure that no tampering of data takes place during transmisssion between the radar, the datacenter and the weather agency. Maintainer

A complex machinery like CASA system can be subjected to a lot of issues. It has to be maintained and troubleshooted in order to bring back the system to normalcy. Maintenance is all about to keep the equipment in operational condition or repair it to its operational mode. Main objective of the maintenance is to have increased availability of production systems, with increased safety and optimized cost. The CASA system has to be maintained in an effective manner. Maintenance management involves managing the functions of maintenance. A significant progress has to be made to maintain the CASA system equipments. As the CASA system equipments are sophisticated and expensive to produce and maintain, maintenance management has to face even more challenging situations to maintain effectively such equipments. In order to maintain the CASA System a maintenance management team has to be developed and trained so as to keep the system equipments in proper condition.

The Maintenance team is also responsible for maintaining a proper security system that is been set up.  The team is responsible for performing routine actions to keep the system in working order or prevent trouble from arising.

Maintenance is of two major types:

Preventive maintenance

Corrective maintenance Preventive Maintenance

Maintenance management team has to perform effectively to avoid failures, unnecessary production loss and safety violations. It is done to keep equipment working and extend the life of the equipment. In order to increase the longevity of the system the team should conduct tests, measurements, adjustments, and parts replacement, performed specifically to prevent faults from occurring. The CASA system can be monitored with help of webcam around the radars. Physical fencing is also a part of preventive maintenance. Corrective Maintenance

Corrective maintenance can be defined as the maintenance which is required when an item has failed or worn out and to bring it back to working order. When equipment fails, it often leads to downtime in production. This is mostly a costly business. Also, if the equipment needs to be replaced, the cost of replacing it alone can be substantial. It is also important to consider environmental issues related to malfunctioning equipment. The Maintenance management team has to be ready any time and should get in the act whenever there is an issue. A proper knowledge about troubleshooting is necessary for the maintenance team.

1.5.2 High Level System Requirement

System Level Requirement

UR: 1.1 Tracking Tornadoes, Hail storm

Sub system Requirements

Requirement number: 1.1.1

Requirement: Radars in unit cell spaced 30 km apart

Components Involved: Radar

Explanation: The radars in the Unit cell have a 40 km ground radius range. The Radars should scan up to heights of 20km to track tornado and hailstorm. The purpose of unit cell is to cover the events accurately in the Doppler region of the radars. So if we calculate by Pythagoras theorem,

40 km

26 km



So, we can see that the center of the beam (red) from radar is approximately 26 km from the ground. So if both the radars are only 30 km apart. They will be able to scan up to 20 km in the Doppler region.

Requirement number: 1.1.2

Requirement: Radars in unit cell should cover cone of silence

Components Involved: Radar

Explanation: The Cone of silence is the region above the radar, where tracking is very difficult unless the radar is looking up perpendicular to the ground. But by having the unit cell arrangement, we should be able to cover the cone of silence of Radar 1 with the Radar 2, as the Radar 2 has coverage region greater than the distance between the Radar 1 and 2.

System Level Requirement

UR: 1.2 Alert the user real time

Sub system Requirements

Requirement number: 1.2.1

Requirement: Alert by website, email, radio, media

Components Involved: Network between Radar and Datacenter, Data center, Network between datacenter and Pulic

Explanation: The public should be alerted real time through the most plausible means of communication. Since the most common devices in use are phones and tablets, email and sms would be the best form of communication. Also, Television and radio are the other best modes to reach the most public who do not have access to smart phones and are not comfortable with sms and emails.

Requirement number: 1.2.2

Requirement: Network speed

Components Involved: Network between Radar and Datacenter, Network between data center and Public.

Explanation: Since the requirement is real time, the data should be flowing through the network without any lag. The speed of the Network is determined by the speed of the end user i.e., the public in this case. The network speed should be higher than maximum speed of the end user's network.

Requirement number: 1.2.3

Requirement: Data center Processing speed

Components Involved: Datacenter

Explanation: The requirement is real time and we have made sure that the network speed is up to the user's network speed .But the data from the radars have to flow through the Data center and get processed before leaving for Public. So the data center should have processing capabilities such that there is not much of processing lag involved in the delivery of data.

System Level Requirement

UR: 1.3 Prioritized tracking

Sub system Requirements

Requirement number: 1.3.1

Requirement: Airport, F1 track on Rank: 1 priority

Components Involved: Radar setup

Explanation: The location of the unit cell is designed such that the Airport and F-1 track will be in the coverage of four radars, so that the accuracy of tracking will be the maximum.

Requirement number: 1.3.2

Requirement: Residential area on Rank: 2 priority

Components Involved: Radar setup

Explanation: The residential area is given second priority next to the Airport and track. The residential area should have dual radar coverage.

Requirement number: 1.3.3

Requirement: Rest of the city on Rank: 3 priority

Components Involved: Radar setup

Explanation: The rest of the city is covered at least by single radar. So no part of the city is left uncovered.

Requirement number: 1.3.4

Requirement: Closed loop architecture

Components Involved: Radar setup

Explanation: The system should have closed loop architecture so that the control from the data center to all radars will help tracking the event closely and accurately.

System Level Requirement

UR: 1.4 Reliability

Sub system Requirements

Requirement number: 1.4.1

Requirement: Backup battery

Components Involved: Radar

Explanation: In case of severe weather event, there is a chance that the radar might be out of power supply. To handle such a situation, the radar should have additional battery backup. This will help in keeping the sensing on till the power supply issue is being fixed.

Requirement number: 1.4.2

Requirement: Primary and secondary Network

Components Involved: Network

Explanation: To make the system reliable, the data should be available all the time from the radars. In the event of failure of routing in a network due to any network element, there is should be an alternative to get the data. In the event of Primary network failure, the secondary network takes the role of primary. It involves a huge cost factor, but it depends on the requirement of the system. The secondary network does not share any network element in common with the primary network.

Requirement number: 1.4.3

Requirement: Primary and secondary Datacenter

Components Involved: Datacenter

Explanation: To handle the case of any software, hardware problems , network attacks or physical damage due to weather events in the datacenter , there should be a fall back option. So a secondary data center should be setup as far away as possible. They will have an entirely separate network connecting them to radars. So they are completely independent to the primary datacenter. In case of failure, the secondary data center will take the role of primary datacenter. There is a huge cost factor involved in this setup, but still it depends on the system's priority.

Requirement number: 1.4.4

Requirement: Fallback radar mode

Components Involved: Radar

Explanation: Whenever the radar fails to receive command from the datacenter, there should be a default mode of sensing for the radar. It might be like leaving the radar to sense in 360 degrees.

System Level Requirement

UR: 1.5 Security

Sub system Requirements

Requirement number: 1.5.1

Requirement: Physical security

Components Involved: Datacenter and Radar

Explanation: The datacenter and radar should be physically well secured to avoid damages from weather events and adversaries. The radar location should be well fenced and not easily accessible by public.

Requirement number: 1.5.2

Requirement: Secure network protocol

Components Involved: Network

Explanation: The network protocol that is used by weather agency and public to access the data should be a very secure one. Since the alerts are high sensitive information, it should have the highest levels of security incorporated in every part of system access.

Requirement number: 1.5.3

Requirement: Encryption to store data

Components Involved: Datacenter

Explanation: The data stored in the datacenters should be encrypted with strong cryptographic algorithms so that any intruders cannot access or modify the data. Causing unwanted alerts due to false data might lead the public to not trust in the system. Trust in the system is very important for evacuation in case of weather events.

System Level Requirement

UR: 1.6 Easily maintainable

Sub system Requirements

Requirement number: 1.6.1

Requirement: Webcam to monitor the radar

Components Involved: Radar

Explanation: A webcam monitoring the radar will help providing maintainers information about the exteriors of the radar. If they are subjected to any damage, the maintainers can reach the spot with the correct replacement.

Requirement number: 1.6.2

Requirement: Diagnosing software in Radar

Components Involved: Radar

Explanation: In case of any failure in radar, the radar should be able to diagnose the problem and send information to maintainers. This will help maintainers to understand the problem and get prepared before they arrive at the location.

Requirement number: 1.6.3

Requirement: Remote Access

Components Involved: Radar

Explanation: The remote access to individual radars will help the maintainers to run the usual diagnosing and calibration routines in the radar and keep them vigil all the time.

1.6 Radar placement:

The Requirements 1.3 deals with the priority of the locations and the coverage needed for different sections of the city. As the requirement stated, the Airport and F-1 track gets four radar coverage. The residential areas get two radar coverage and other parts get single radar coverage. The data centers are situated such that the primary data center is in the center of the city and the secondary datacenter lies far away from the primary data center.

Airport and F-1 Track

Perimeter of Indianpolis It can be observed that the radars are placed strategically such that whole city gets a Doppler coverage. The Airport and track are well within the overlapping region of four radars. Even the residential area gets the four radar coverage as opposed to asked two radar coverage. The data centers placed can be seen from the picture below.

C:\Users\Badri\Desktop\radar w data center.jpg

The data centers are placed far apart, such that they are not affected in the same time and thus form a reliable system.

1.7 Cost Calculation:

Instead of providing a figurative estimate of the whole system, we decided to highlight the factors that are primary and important to be considered for the cost calculation. They are as follows

Radars , backend computer with software for diagnosis and hardware to monitor and protect, battery backup for power

Physical security around Radars

Primary network and secondary network from radar to datacenter, the intermediate routing elements. Since there are two parallel networks, cost doubles.

Datacenter with hardware and necessary software, physical security, maintainers and their power supply needs and the battery backup.

Primary and secondary datacenters for reliability, but doubles the cost.

System to deliver the alert information to media, radio, sms and email .The system can be a full time human resource or software to track the changes and update it in all media.

Maintainers for the whole system, who will diagnose radars, datacenters and network setup.