Senior Design I EEL 4010 T-R 5:40pm to 6:55pm Professor Wilmer Arellano Senior II Proposal April 12, 2006

1. Hung Le (Electrical Engineering) Panther ID 1076452 2. Nadeem Ahmad (Computer Engineering) Panther ID 1495139 3. Nasir Malik (Computer Engineering) Panther ID 1333340

1 Efficient Parking Meter Controller using Autonomous Wireless Reporting

2 Table of Contents 1. Table of Contents...... 3 Table of Figures...... 4 List of Figures ...... 4 2. Acknowledgement ...... 6 3. Executive Summary ...... 6 4. Introduction ...... 6 A. Problem Statement ...... 6 B. Project Objectives ...... 7 C. Constraints ...... 8 D. Assumptions and Limitations ...... 8 E. Operating environment ...... 8 F. Intended user(s) and intended use(s) ...... 8 G. Needs Feasibility Analysis ...... 8 H. Background ...... 11 I. Concept Development ...... 19 J. Intellectual Property Consideration...... 21 K. Standards Considerations...... 23 5. End Product Description and other Deliverables ...... 25 A. End Product Description ...... 25 B. Functions ...... 26 C. Specifications ...... 27 6. Strategy...... 27 6. Ethical Considerations and Social Impact...... 32 7. Multidisciplinary Aspects ...... 34 8. Personnel ...... 34 10. Budget ...... 35 11. Conclusion ...... 36 12. References ...... 36 3 Table of Figures

1. Cause-Effect Fishbone ...... 9 2. Parking Finder Transmission ...... 10 3. Parking Finder Reception ...... 11 4. Magnetic Sensor ...... 12 5. Magnetometer Calibration ...... 14 6. Sensor Transmission ...... 15 7. Sensor Receiver ...... 15 8. Receiver flowchart ...... 15 9. Transmission flowchart ...... 16 10. RFID System ...... 17 11. PDA sample ...... 17 12. RFID System ...... 18 13. Concept Development Flowchart ...... 19 14. System’s Block ...... 25 15. Function’s Black-Box...... 26 16. WBS...... 29

4 List of Tables

1. Feasibility Analysis ...... 9 2. RFID User Case...... 17 6. Decision Process Table ...... 19 8. Budget Table ...... 35 15. Gantt Chart...... 31

5 I. ACKNOWLEDGEMENT

This project would not be possible without assistance from Professor Arellano, who provided us with his advice and instructions at all the stages of writing proposal.

II. EXECUTIVE SUMMARY

The goal of our project is to design an efficient Wireless Parking Meter Enforcer. The newly proposed system will improve all the inefficient aspects of the already existing method of controlling the parking facilities. The system will be able to reduce the human interaction in controlling the parking facility as much as possible, while giving the precise and accurate results. The system will be very space efficient and isolated and it will not interfere with continuous flow of traffic in parking lots. Since coverage area (based on the parking spots) is enormous for any medium to large size parking facility in metropolitan areas, the unit cost for the system will be low and very low to accommodate any real parking lot practically. System will consist of three major parts: Transmitter, Receiver, and Graphical User Interface on a PC with the results. The whole product will be insensitive to rough weather conditions and signal strength from transmitter to receiver will be good enough in all types of weather. The project turned out to be feasible and marketable with a high possibility of success, after assessing and running the feasibility test.

III. INTRODUCTION

Urbanization has increased rapidly in the recent history and so did the lifestyle of people living in big congested cities. One of radical brought by this urbanization is the method of transportation in cities considering the busy adhesive way of living. With an exception of some cities in US, subway systems or any other public transportation are not very efficient, number of automotive vehicles per capita is all time high. More cars mean bigger parking lots and bigger parking lots mean more effort to keep discipline and control in parking lots. Even though there are many other concomitants of vast urbanization in the area of traffic increment, we will be focusing on the management and better organization of parking garages.

A. Problem Statement

Most parking garages in metropolitan areas are compact and multistoried with hundreds (if not thousands) of parking spaces available for parking at any given time. Second popular type of parking facilities also consist of hundreds of parking spots but covering a wider area for parking. The second types of parking facilities are usually without roof and are on the sides of the main roads (e.g. Miami Beach open parking system in our city or downtown). These types of parking facilities are mostly operational 24 hours a day and 7 days a week. People are charged based on the parking time (ranging from minutes to hours a day), which make their operation very dynamic. To control the whole system (first of second type), it is very important to enforce discipline on these parking facilities.

6 Current enforcement of these parking facilities is achieved by using parking meters and parking attendants or security guards. Based on the size of parking facility, one or more parking attendants continuously roam around the parking lots and see if there is any car parked on any spot with an expired meter. Appropriate action is taken then, if a car is illegally parked. By looking at the whole system carefully, the most inefficient portion of the whole operation seems to be the manual roaming and looking at the each parking spot by parking attendants. A more efficient parking enforcement is required. Our system will mainly be focused on the manual roaming and visually monitoring each expired meter. We will be working on a system that will monitor each parking spot autonomously and report any violations wirelessly to the parking attendant with the information of the parking spot where violation is taking place with exact location. A database system of all locations on a computer with an easy to use, end user graphical interface will help display the results in proper and readable manner.

B. Project Objectives

1. Reduce Human Interaction 1.1 Detection and reporting of an illegally parked car should require no human work or effort. 1.2 System should be autonomous in all phases and end results should be clear and user friendly so no interpretation of results is required. 1.3 Wireless reporting the car with expired meter should be frequent (around one to three minutes per parking spot). 2. System should be inexpensive 2.1 Implementation should be practical 2.1.1 System should be cheap enough so it could be implemented on very big parking garages 2.1.2 Cost should be low enough so that replacement of parking attendant with this system could be worth it. 2.1.3 Individual cost of each part in the system should be low so it could be replaced effectively if needed. 2.2 With a low cost, system should be marketable.

3. Lifetime of the system should be extensive 3.1 System should be insensitive enough to work in extreme weather conditions and last for a long time. 4. System should cause no interference with any parking lot operations 4.1 The whole circuitry should not interfere in any of the parking lot operations. 4.2 All devices and wires should be isolated and invisible to the moving vehicles to avoid any damage to any of the devices.

We will be designing a system to cover all of the previously mentioned specifications. In addition, the system would be wireless and autonomous with minimal human interaction requirement. The installation and function would be time and cost effective and lifetime of the product would be extensive. The system will ensure that all the illegally parked cars are reported in an efficient manner.

7 C. Constraints

 System must be waterproof for roadside and open parking lots and must be weather resistant because of its usage in the hot/cold and humid parking garages.  Active flow of traffic in the parking garage should not be disturb by the system (or any component of the system).  General installation (equipments) should be less than $1000 for a medium parking garage with the decrement of relative (number of parking spot and cost per spot) expenditure exponentially, as the number of parking spots increase.

D. Assumptions and Limitations

1. Assumptions: Sensors for the systems are not tampered with and either there are specifically designed spot for motorcycles or motorcycles are parked properly. 2. Limitations: Distance between transmitter and receiver cannot be more than a thousand feet in an open space parking facility. Only one parking spot is checked and reported (if necessary) at a time, within a segment containing one transmitter. There should be backup power in the case of power outage to keep the system running.

E. Operating Environment

The parking meter enforcer must be able to perform outdoor in an uncontrolled temperature and humidity level. The environment in which the system works could be hot and humid such as Florida or dry and cold such as Maine. Outdoor systems should even be more insensitive to weather conditions since their operating environment could be dirty dusty, or with heavy rain or snow.

F. Intended User(s) and Intended Use(s)

1. Intended User(s): This system is designed for public or private parking lots so intended user could be any commercial parking garage manager or owner any government regulated public parking garage contractor. End user for this system is the data collector and operator of the specific parking facility. 2. Intended Use(s): The basic purpose of this system is to detect a parking violation and report it in an efficient manner with readable Graphical User Interface on a computer with the detail of the location where violation has occurred.

G. Needs Feasibility Analysis

1. Need Analysis:

8 Survey Possible Problem Agree Disagree May Total Be Number of Participants Parking attendants are not active enough 2 8 0 10 Equipments are outdated 6 3 1 10 Not enough parking attendants 7 3 0 10 Penalty for illegal parking is too soft 1 7 2 10 Parking garages are too big as a single entity 9 0 1 10 to control by human at all times with increasing number of cars Expensive Labor for hiring more people 10 10 0 10 Transportation for the officer to get to 3 7 0 10 violating vehicle

Cause-Effect (Fishbone) Diagram

We used cause-effect fishbone diagram to conclude the need analysis. According to the survey, research and observation, it was concluded that “lazy parking attendants” and “transportation problem for attendant” is not a valid cause of inefficiency in controlling parking garages. Even if we assume lazy officer to be an issue, it would hardly be solvable since every person is different with an active or passive approach toward his or her work. Increasing number of cars in metropolitan areas as a cause is still under investigation since it requires some data collection of the increase of the number of cars and new parking garages built and ratio between them. Visual inspection which corresponds to the each meter with unique reading and too many parking spots to cover in general is obviously a valid and fair reason which contributes to the inefficiency and

9 with this strong and vivid in mind our objective will be focused to reduce or remove all visual inspections of meters in any number of parking spots.

2. Feasibility Analysis:

Attribute W S W.S. Why? Solution .5 5 2.5 There are timing For minor tasks, work will R1 Meeting problems in group be divided into 2 or 3 conflicts meetings because of parts. Necessary the different job meetings will take place timings of group in nights or early members mornings

R2 Sufficient .5 3 1.5 A group of three Enough. People people. .75 2 1.5 We do not know much One team member will be R3 Sufficient Skills about Coding a GUI in taking a course in Visual Visual BASIC or Visual C# C# .8 5 4 After considering Not Required R4 Sufficient Microcomputer Lab, Equipments Logic Lab, and Systems lab, we think that we have sufficient equipments R5 sufficient .5 5 2.5 General understanding A few more meetings will understating of of the task seems to be be held after proposal task clear in all members revision to finalize the concept understanding S1 What are the .8 5 4 After analyzing all the Not Required chances of circumstances, we meeting the think that it will be OK. intermediate mileposts E1 What 1 5 5 We have all the funds Not Required percentage of total required. funds required do we have Total 21 Weighted Scale 4.33 Feasibility Analysis Table

After analyzing the feasibility of the whole project and different components, we concluded that there are a few obstacles in some aspects of the project but in general, the project seems to be doable. Major skill required for the project is the design of the database system and graphical user interface design in any RAD (rapid application developer) computer language. Even though two of the team members are computer engineers but a dynamic application with serial port for data has never been designed by any member. We will be purchasing books and searching websites regarding the relating

10 material and two of the team members will be taking advance course in Visual C# and windows programming in summer as well.

H. Background

The following three projects are about systems that were developed to efficiently manage and control as well as simplify a specific aspect on the activity of parking. The first project is about a parking finder system, the second is about an automatic parking meter enforcer and the third is about an RFID based parking ticket system. Together the three systems cover all the major and minor details of parking and the combination of their ideas results in a modern and technology based parking system.

1. Parking Finder:

The first design that we look upon in or research was the one done by Mohamed Eissa and Mohamed Elhag at University of Illinois in Fall 2004. The main aspect of this project was to create a system that utilized the driver in finding a parking within a geographical area. The systems have to be reliable, cheap and user friendly. The design consists of three main parts: a wireless sensor network, a central processing unit, and user application. Each node in the design network consists of three- tiered architecture composed of a sensor circuit connected to a Mica2dot radio/processing board through a data acquisition board (MDA500). The sensor circuit detects the car presence by converting magnetic field strengths into a differential output voltage. The outputted voltage is then transmitted using a Mica2dot radio/processing board to the base station. Below is the block diagram of the full system under operational mode.

Data Acquisition Magnetometer Board Sensors (MDA500)

Antenna (Transmission) Processor/Radio Board (MICA2DOT)

System Reception Diagram

11 Antenna (Reception) Processor/Radio Interface Board Board (MIB510) (MIC2DOT)

Personal Computer Internet (Processing Unit)

Laptop/PDA (User Unit)

Figure 1: Block Diagram

First the sensor will detect and determine if the parking lot is empty, then it will sent the information to the Data acquisition board, which will be sent to the radio processing board where it will be transmit using the antenna. The data that is being broadcast by the transmit system will be receive by the reception which will convert the data into user basic language.

The system operate like a synchronous machine, where it would automatically update it information during a specified times so the user can find out real information about what parking lot is empty and which are not. According to the designer, the sensors that they chose was the magnetometer sensor because the magnetometer utilized the simplest circuit and provided excellent efficiency and are cost effective. Below is diagram as well as the graphical analysis of the magnetometer sensor.

Magnetometer (HMC1001) Calibration

12 As stated in the final report by the designer, the best position for the sensor placement would be one foot above the ground and about one foot underneath the car.

2. Automatic Parking Meter Enforcer

This project was done by Jeffrey Cheng, Chris Chang, Jeff Bruggemann in University of Urbana Champaign Illinois in Spring 2003. The purpose of the second project was to design a more efficient system of parking meter enforcement to replace the extremely out of date current system. Our new design will feature a system of parking meters that will automatically detect the illegally parked vehicles, and alert the violation to a remotely located officer, and showing the officer the location of the violation. The design of the parking meter enforcer consisted of three phases. 1. Detection: The meter circuitry detects the illegally parked car. The meter circuit consists of a countdown timer to represent the meter timer display, and an ultrasonic proximity sensor to detect the presence of the vehicle. Detection requires ultrasonic sensors, amplifiers, and a comparator for the car sensing circuit. The meter countdown timer requires a 555 circuit, BCD counter, BCD-to-LED display converter, and an LED display. 2. Transmission: When the detection circuit senses an illegally parked car, the number of the meter space where the violation occurred is transmitted to a remotely located officer. The transmission portion of the meter requires a Basic Stamp to process the inputs, and a LINX transmitter module to send the information from the Stamp. 3. Reception: The reception circuit received this meter number and looks up its location from a stored database. This location is displayed to the officer on a Visual Basic user interface. It requires a Basic Stamp, LINX receiver module, A/D chip, and a laptop/computer. The Basic Stamp takes in information from both the LINX chip and the A/D chip and sends the resulting information to the computer which displays everything in a user-friendly format. The first design consideration faced was what type of sensor to use. After various considerations, the ultrasonic transceiver pairs were chosen for their size, availability, and most importantly, price. The sensors work in pairs; one acts as a transmitter, and the other becomes a receiver. The sensors need to be placed side by side, not facing each other. What happens is that the transmitter will transmit a 40 kHz wave into the open space. If a car is present, the wave will hit the car and bounce back, which will be

13 received by the receiver, and further circuitry will convert that received signal to a dc HIGH to be sent to the transmitter to transmit.

Sensor Transmitter Circuitry: The function of the transmitting part of the sensor’s circuitry is basically to generate a 40 kHz wave, and give it some amplification so that it would be large enough to transmit. The 40 kHz wave was generated by a 555 timer, and a KF347 op-amp was used to amplify the 40 kHz signal. The schematic for the sensor transmitter circuit is as follows:

The sensor transmitter uses a 555 Timer to generate a square wave at 40 kHz. The 555 timer frequency of operation is determined by the time constant between R1, R2, and C. f = 1/(.693 x C x (R1 + 2 x R2)) where f=1/t [1] t1 = .693(R1+R2)C t2 = .693 x R2 x C

Internal comparators check the voltage across C to determine when to charge and discharge. The voltage across C is charged to 2/3Vcc before it discharges. It falls to 1/3Vcc and begins to charge again.

Sensor Receiver Circuitry: The function of the receiving part of the sensor’s circuitry is in essence to receive the bounced back wave and somehow convert it to a dc HIGH when a car is sensed. First of all, since the received signal was so small, it had to be amplified, and a RCA 027 amplifier was used for that. Next, a rectifier circuit which consists of a 1N4001 diode and a 0.01 uF capacitor was used. The 1N4001 diode rectifies the signal, and the capacitor smoothes out the signal so that it is close to a dc. Finally, this signal is run through a LM339 comparator, which is compared to a reference voltage of 5 V. If a car is sensed, then the signal will have a dc value of greater than 5 V, and a dc HIGH will be outputted. If a car is not sensed, then the signal of course will have a dc value of less than 5 V, and a

14 dc LOW will be outputted. The schematic for the sensor receiver circuit is as follows:

The transmission circuit is shown in figure 1 of section 3.7. The LINX receiver is used in the open space locator design as discussed later, and may be ignored here. The Basic Stamp takes the two inputs from the detection circuit to determine if the car is in violation. The Basic Stamp has sixteen available I/O pins, of which one is used to send out the data stream, thus the remaining I/O pins allow for up to seven meter spaces to be under surveillance at once. Since one sensor circuit and timer display circuit was built, the extra spaces were simulated with switches to signal to the Basic Stamp when a vehicle was present and if time was remaining. The Basic Stamp keeps track of the amount of time elapsed and each individual meter number, coding it into a bit string. The string is sent to the LINX transmitter to transmit the individual meter number and time elapsed for the illegally parked vehicle.

Car Timer Sensor Output Output

Are both high? Yes

Time = Time + 1 min No

Transmit Meter Time = 0 Number and Time to LINX chip

Pause (1 minute)

The reception circuit is shown in figure 2 of section 3.7. The LINX transmitter is used in the open space locator as discussed later, and may be ignored here. The receiver 15 circuit begins with a LINX receiver to receive the transmitted meter number. This bit stream is sent to another Basic Stamp, with an agreement in baud mode with that of the transmitting Basic Stamp. The Basic Stamp decodes the data into decimal format for use in the Visual Basic GUI. The Visual Basic GUI finds the meter number contained in the database and displays the location. A feature available on the LINX receiver is a signal strength indicator pin (RSSI). This pin outputs a voltage between 800 mV and 2.5V depending on the strength of the signal [3]. We used this signal with an A/D converter to give us a signal strength number, with which we could compare each transmission and sort in order of relative proximity. The A/D is controlled by three Basic Stamp I/O pins which use synchronous communication to shift in the 8 bit result.

3. RFID Parking Violation Enforcement

In the summer of 2005, University of Arkansas Transit and Parking moved to a new type of parking sticker that required everyone to affix a removable static-affixed label to the window of their vehicle. The label contains information on parking permissions and vehicle identification. These new labels were equipped with barcodes to allow a scanner on the Parking Controller’s unit to read the tag information and then generate a ticket. The Parking sticker will contain an RFID tag with a unique serial number. This number will be tied to the customer’s data in the same way the existing numbers on the current parking stickers are. For development purposes a test database will be set up on a MySQL server using a small set of manually entered data.

16 The Parking Controller input device will consist of a PDA or PC equipped with a Compact Flash RFID reader and an 801.11b wireless card.

The input device will download a small subset of the database upon docking; if a network connection is not available, this data will allow the Controller to verify that the tag on the car matches the make and model of the car in the database. The user interface of the Controller would then allow the controller to fill in the specifics of the ticket. After the ticket is written, the device would then transmit the ticket to the central database via wireless in a secure manner. If a signal is not available or the system doesn’t get a response from the database server then the ticket is stored until docking.

17 System Diagram

RFID Parking Tag

Docking PC at Parking Control

Wireless Access Point RFID Reader `

Docked RFID Reader

Web Database Server Server

Use Cases

Use Case: Parking Control Officer scans RFID tag. Primary Actor: Parking Control Officer Goal in Context: The RFID tag provides a permit ID that is then used to query a remote database. Preconditions: The RFID tag must be readable by the handheld reader. The ID provided by the RFID tag must refer to a valid entry in the remote database. Trigger: The Parking Control Officer activates the RFID reader. Scenario: In order to check a vehicle's information, a Parking Control Officer must aim the RFID reader at the RFID tagged permit and scan it. The ID acquired from the tag is then used to query a remote server based database for information on the vehicle to which the RFID tag is applied. Priority: High Exceptions: The RFID tag is improperly encoded. The RFID reader improperly reads the RFID tag. The ID acquired from the RFID tag is invalid. Open Issues: The RFID tag has been tampered with. The RFID reader is malfunctioning.

18 I. Concept Development

Controlling a Parking Garage

Manual Mechanical Wireless RFID Decals Inspection Gates Notification s

Determine a car Scan all Scanner at Manual Scan for Wireless Data parked with Cars at Each Parking Time Check Transmission expired meter Entrance Spot

Scanner and Data Multiplexing Transmitter Transmitter Receiver and Transmission at All Spots

Parking Spot Logic Gate Identification Receiver Based

Microcontroller

Voltage Difference Microcontroller PC with at Sensors Based GUI Display

There could be many different ways in which the basic idea and general purpose of the whole project could have been achieved, as shown in the picture. Many different possibilities were explored and analyzed and Wireless Notification system was chosen. One basic way to control a parking garage remains the most basic method i.e. Manual Inspection. This method is mostly used these days and details of it being inefficient have been discussed previously.

 Advantage: There are no needs of any electrical circuits and there are no discrepancies based on power failure circuitry expiration or any other technical issues.  Disadvantage: More than one parking attendants required in big parking garage which imply high labor cost and more work for each parking attendant. 100% accuracy is still not possible and roaming around in garage all the time could be dangerous.

19 Another method in use these days is to have mechanical gates at the entrance and exit of the parking garage. Parking attendant checks the tickets and charge (on exit) on the bases of time spent in the parking garage, reflected by the ticket.  Advantage: No manual roaming is required which reduces the work of parking attendant and labor cost is reduced (compared to the first option) as well. There is no need to place meters in the parking garage, which could save a lot of money.  Disadvantage: This method has some issues associated with it. First of all, open space parking at roadsides cannot be covered with this method at all. In terms of using this method in closed roof parking garages, it requires an all time presence of a parking attendant at the gate so more than one parking attendants are needed to inspect the cars in the garage and check the tickets at entrance and exit.

RFID scanners placed at parking spots could be one way of achieving the task and the cars entering the parking garage must have the RFID decal. The scanner would scan the decal upon parking and keep the record of the time for which the car was parked.  Advantage: Data is automatically kept and there is no need to manually inspect the parking spaces. Placing extra decals and configuring them to maintain the record is also easy.  Disadvantage: Scanning all cars with RFID decals has very limited use since it could only be applied at private parking garages (and usually private garages where same people park everyday don’t usually pay for parking anyway). RFID tag could be placed on each parking spot but this is obviously very inefficient way since a scanner will have to be placed every few feet and will end up being very expensive.

Finally, the wireless notification using one transmitter and one receiver and sensors one each parking spot seems to be the best option. There are two ways of achieving the goal. First is to place a microcontroller at each cluster (could consist of as many parking spots as I/O pins available on the microcontroller) of parking spots and receive the data, sort it and display it on the computer.  Advantages: It is obvious that design of this system using microcontroller is much easier since each I/O pin can be identified (therefore, the parking spot can be identified separately.  Disadvantages: There are limited numbers of I/O pins on any microcontroller and considering thousands of parking spots, it is not practical to cover all the area with expensive microcontrollers.

Second method that we chose is to use logic gates (instead of microcontroller) with the combination of sensors to transmit the information the parking spot where the car is illegally parked. There are some advantages and disadvantages associated with using logic gates instead of microcontroller  Advantages: Encoders could be a better option to identify the parking spots and the circuitry is much cheaper than microcontrollers, easier to replace, and in fact practical to cover thousands of parking spot in any medium to large size parking garage.  Disadvantages: It is hard to uniquely identify individual parking spot using logic gates and multi-spot reporting at single time is not so obvious as well. Compared to microcontroller, logic gates are not programmable and any change to the system will require much more hardware changes.

20 Design Constraints RFID Decals Encoder Based Javelin Stamp with Scanner Wireless Based Wireless Notification Notification C: Must not be effected by dust y y y C: Must be rust/shock (minor) proof y y y C: Interconnectivity and y y y Compatibility C: Should not get in the way of traffic y y y C: Small enough to be networked n y y C: Cannot cost more than $200 y y n C: Signal strength n y y Design Objective Weight Score Weighted Score Weighted Score Weighted (%) Score Score Score O: Product lifetime 15 0.90 13.5 0.85 12.75 0.90 13.5 O: Reporting accuracy 10 0.98 9.8 1.00 10 0.92 9.2 O: Design and Installation simplicity 25 0.5 13.5 0.90 22.5 0.95 23.75 O: Reduce Human Interaction 35 0.85 29.75 0.95 33.25 0.90 31.5 O: End user ease of understanding 10 0.75 7.5 0.90 9 0.85 8.5 O: Minimum Cost 5 0.5 2.5 0.95 3.5 0.50 2.5 Total 100 76.55 92.25 88.95

J. Intellectual Property Consideration

After a detailed search at the US patent office’s website, we were able to find out the system we are planning to design has already been built by Howard; Charles K. (Somerville, MA); Cayetano; Kenroy (Boston, MA); Omojola; Olufemi (Boston, MA) under the company name of VehicleSense, Inc. (Cambridge, MA). Patent was filed in February 7, 2002 with the appeal number 072808. The abstract of their claim is as follows “The systems described herein include one or more wireless vehicle detectors, along with a distributed parking payment system such as parking meters or a paystation. Information from the payment system and the vehicle detectors may be combined to determine when a parking violation occurs, or is about to occur. This information may then be transmitted through a communication system to a parking enforcement officer, along with information about the geographic location of the violation. The information may also, or instead be transmitted to a parking payer to notify the payer of an impending infraction so that the payer may purchase additional parking time before the violation.” Brief points of their claims are following

1. A system comprising: a sensor for detecting the presence of a vehicle within a parking space; a parking meter associated with the parking space and being remote from the sensor, the parking meter configured to receive a payment and the parking meter including a timer that allots time according to the payment; a host, the host having a wireless connection to the remote sensor for providing a communicating relationship with the remotely located sensor and the host connected in a communicating relationship with the parking meter, the host configured to monitor 21 the remotely located sensor over the wireless connection and to monitor the parking meter.

2. The system of claim 1 further comprising a base station for maintaining communications between the sensor and the host.

3. The system of claim 1 wherein the host determines when a payment for a parking space is about to expire and generates a notification to a payer who has paid for use of the parking space.

4. The system of claim 3 wherein the payer is notified through at least one of an electronic mail message, a telephonic message, or an electronic page.

5. The system of claim 1 wherein the host notifies at least one enforcement official of the violation by transmitting a message to a device used by the enforcement official.

6. The system of claim 1 wherein the parking meter is a pay-station that manages payments for a plurality of parking spaces, the host being physically located within the pay-station.

7. The system of claim 1 wherein the host and the parking meter communicate through a wireless interface.

8. The system of claim 1 wherein the parking meter employs a wireless payment process.

9. The system of claim 1 further comprising a plurality of sensors and a plurality of parking meters arranged to monitor parking in a parking area, the parking area being at least one of a parking garage, a parking lot, or a public street.

10. A method comprising: receiving over a wireless connection a first signal from a sensor located at a parking space, the first signal including data concerning the presence of a vehicle in the parking space; receiving a second signal from a parking meter associated with the parking space and being remote from the sensor, the second signal include data concerning payments received by the parking meter for use of the parking space; determining when a parking violation has occurred, the violation occurring when data in the first signal indicates that a vehicle is present in the parking space and the data in the second signal indicates that there is no current payment for the parking space; and in response to the parking violation, generating a message to an enforcement official notifying the enforcement official of the parking violation and a location of the parking space in which the parking violation has occurred.

11. The method of claim 10 further comprising determining when a payment for a parking space is about to expire and generating a notification to a payer who has paid for use of the parking space.

12. The method of claim 10 wherein generating a message to an enforcement official includes transmitting the message to a wireless device used by the enforcement 22 official.

13. The system of claim 10 wherein the enforcement official is a private towing company.

14. The system of claim 10 wherein the parking meter is a pay-station that manages payments for a plurality of parking spaces.

15. The system of claim 10 wherein the parking meter receives payments through a wireless payment process.

16. A computer program product comprising: computer executable code for receiving over a wireless connection a first signal from a sensor located at a parking space, the first signal including data concerning the presence of a vehicle in the parking space; computer executable code for receiving a second signal from a parking meter associated with the parking space and being remote from the sensor, the second signal include data concerning payments received by the parking meter for use of the parking space; computer executable code for determining when a parking violation has occurred, the violation occurring when data in the first signal indicates that a vehicle is present in the parking space and the data in the second signal indicates that there is no current payment for the parking space; and computer executable code for, in response to the parking violation, notifying an enforcement official of the parking violation and a location of the parking space in which the parking violation has occurred.

K. Standards Considerations FCC § 2.202 Bandwidths.

(a) Occupied bandwidth. The frequency bandwidth such that, below its lower and above its upper frequency limits, the mean powers radiated are each equal to 0.5 percent of the total mean power radiated by a given emission. In some cases, for example multi-channel frequency- division systems, the percentage of 0.5 percent may lead to certain difficulties in the practical application of the definitions of occupied and necessary bandwidth; in such cases a different percentage may prove useful. (b) Necessary bandwidth. For a given class of emission, the minimum value of the occupied bandwidth sufficient to ensure the transmission of information at the rate and with the quality required for the system employed, under specified conditions. Emissions useful for the good functioning of the receiving equipment as, for example, the emission corresponding to the carrier of reduced carrier systems, shall be included in the necessary bandwidth. (1) The necessary bandwidth shall be expressed by three numerals and one letter. The letter occupies the position of the decimal point and represents the unit of bandwidth. The first character shall neither be zero nor K, M or G. (2) Necessary bandwidths: Between 0.001 and 999 Hz shall be expressed in Hz (letter H); Between 1.00 and 999 kHz shall be expressed in kHz (letter K); Between 1.00 and 999 MHz shall be expressed in MHz (letter M); 23 Between 1.00 and 999 GHz shall be expressed in GHz (letter G).

According to this standard, we will be expressing the bandwidth used by our wireless transmitter to be 210M50-216M00. Since the first system we will be designing for senior II is not marketed and commercial based. The system is considered “Home- built device” under chapter FCC provisions part 1 and chapter 15, so we will be complying with § 15.25 which is as follows;

FCC § 15.23 Home-built devices.

(a) Equipment authorization is not required for devices that are not marketed, are not constructed from a kit and are built in quantities of five or less for personal use. (b) It is recognized that the individual builder of home-built equipment may not possess the means to perform the measurements for determining compliance with the regulations. In this case, the builder is expected to employ good engineering practices to meet the specified technical standards to the greatest extent practicable. The provisions of § 15.5 apply to this equipment.

With the frequency used for transmitting the data ranges from 210.5MHz to 216MHz, we will be incorporating our design with the following FCC regulation in part 1 chapter 15,

FCC § 15.241 Operation in the band 174–216 MHz. (a) Operation under the provisions of this section is restricted to biomedical telemetry devices. (b) Emissions from the device shall be confined within a 200 kHz band which shall lie wholly within the frequency range of 174–216 MHz. (c) The field strength of any emissions radiated within the specified 200 KHz band shall not exceed 1500 micro-volts/meter at 3 meters. The field strength of emissions radiated on any frequency outside of the specified 200 kHz band shall not exceed 150 micro- volt/meters at 3 meters. The emission limits in this paragraph are based on measurement instrumentation employing an average detector. The provisions in § 15.35 for limiting peak emissions apply.

For the serial communication between receiver and the computer serial port, RS- 232, RS-422, RS-423 and RS-485, (from EIA (Electronics Industry Association)) Serial Interface Standards will be incorporated. RS-232, 423, 422 and 485 specify the communication system characteristics of the hardware such as voltage levels, terminating resistances, cable lengths, etc.

RS-232

RS-232C is the oldest and most popular serial communication standard. It is the standard used on PC COM port hardware. It is designed to connect two systems only and is "single ended", meaning that it uses one wire for data and one for ground. It is a robust interface with speeds to 115,200 baud and will withstand a short circuit between any 2 pins. Maximum signal voltages are ±15 volts. Cable length depends on baud rate but is typically 50 feet at most.

24 RS-423

RS-423 is similar to RS-232C except that it allows for higher baud rates and longer cable lengths because it tolerates ground voltage differences between sender and receiver. The maximum signal voltage levels are ±6 volts. Ground voltage differences can occur in electrically noisy environments where heavy electrical machinery is operating.

RS-422

RS-422, like RS-232, is used to connect only two systems. It uses differential, or "double ended" data transmission, which means that data is transmitted simultaneously on two wires between two stations independent of the ground wire. Each signal requires 2 wires with a ground present in the system. The advantage of this method over RS-232 is higher speeds and longer cable lengths - 4000 feet at a 100K baud rate, for example.

RS-485

RS-485 is an improved RS-422 with the capability to connect up to 16 devices (transceivers) on one serial bus to form a network. Such a network can have a "daisy chain" topology where each device is connected to two other devices except for the devices on the ends. Only one device may drive data onto the bus at a time. The standard does not specify the rules for deciding who transmits and when on such a network. That's up to the system designer to define.

IV. End Product Description and other Deliverables

A. End Product Description

After all the necessary design and implementations, system will consist of four major parts. First section will have sensors placed on each parking spot to detect if there is a car present and it will be combined with a timer to simulate the meter. When timer is reporting the meter to be expired and sensors are reporting the presence of a car, the data will be sent to the transmitter. They will report the parking spot number and other data to the transmitter. Second section will be of a transmitter that will transmit the data to receiver wirelessly so in other words transmitter interacts with the receiver. Third section will consist of a receiver and a microcontroller which will take the data and sort it and send it to the computer using serial port. Fourth and final section will be a GUI (Graphical User Interface) designed in Visual Basic or Visual C# to display the data in a user friendly manner. Microcontroller checks any new data at receiver and if there is, then is forwarded via serial port to the computer. General description of the product will look as follows

Sensors Graphical Transmitter Microcontroller User Receiver Interface Timer

25 System’s Flowchart Diagram

B. Functions

Ultrasoni c signal

Noise

Transmission

Amplification Pulse Generation

Comparator Amplification

555 Timer

RF Noise Sign Filter al

Output from LINX receiver

Any Data?

A/D output Bit 0-255 String

Display

26 C. Specifications

Hardware

 Operating Wireless frequency: 216 MHz  Deviation: ±15 kHz (max)  Spurious radiation: 55 dB below carrier  Sensor and Timer Block input Power: 9V battery  Receiver Block’s input Power: 9V battery  Display: Pentium 4 PC  Environment: Visual Basic runtime environment  Internal Communication: Serial communication port  Battery: Precision compartment auto-adjusts to accept any known as alkaline battery.  Receiver Block Weight: 10.3 OZ. including battery  Receiver Block Dimensions: 5.1 x 3.4 x .75 inches  Temperature: -10F to 135F

V. Strategy

A. Plan of Action

The general issue that our team will be facing is the short term semester of summer for senior design II class. Our focus on planning the right strategy is one of our utmost preferences. We will welcome any and all help offered by any person such as any professor’s assisting or any book or research article available to get the task done. The necessary steps that are planned to be taken are as in the following order. First step is to get the project approved by Professor Mohammad and take any feedbacks from him. All the suggestions or requirements added to the project (or any changes) by Professor Mohammad will be discussed in the team and necessary course will be taken to fulfill those requirements. The first step in implementing the project would be to divide the project into a few subsections each independent from other in terms of functionality. With the team discussion and agreement, time slots will be allotted to each sections and each member will be assigned major or minor role in the section according to his specialty. This plan will be discussed with the mentor and any suggestions or requirements will be added to the plan of action. We will also be considering any sections of the project which could be worked on at the same time in the parallel fashion. We will also be working on the software section of the system i.e. designing Graphical User Interface for the results, from the start. It will be one of our highest priorities to make list and order all the possible required parts for the system so that there is not time wasted in next semester to order the parts, receive the shipments, and deal with any replacement (if needed). As the project implementation proceeds, changes in the design (whole system or a subsection) will be considered. After the hardware and software parts are completed, testing different scenario will start and we will try out all the possible cases and work on any improvements. At the end of

27 the project, all the errors will be sorted out and product will be optimized to deliver best and accurate results.

B. Statement of Work

1. Scope of Work

The project basically covers three areas in terms of development. The most obvious is the electrical circuitry including the logic design PC board connections. The second areas of the work consist of RF components including transmitter and receiver. Transmission and reception part of the whole system could be isolated and independent from the rest of the system. Final part of the circuit includes coding an application for the visual display of the results. 2. Location of Work

Most of our work will be done in the system's lab and the Logic Design lab. Some tasks may require us to use microcomputer lab and DSP lab (if necessary). We currently have no plans (or see any requirement) to work anywhere other than the lab at university, since it is the most convenient place for all group members and any help needed at any point (from mentor or any other professor) is available without delay. 3. Period of Performance

Since all of the team members will be taking other courses at the time of taking senior design II, most of the time spent on the project will be in between or after other classes. Meetings of weekends will be considered based on the need and there is no advance planning regarding the time fixture. 4. Deliverables Schedule

More specific and detailed list of deliverables can be seen in Gantt chart but the research phase would start even before the semester starts and our plan is to build the prototype system providing the basic expected results in 6 weeks. Another 4 weeks will be reserved for optimization and the last 2 weeks will be spent on testing. The product should be delivered in full working condition at the end of July or the start of August.

28 C. Work Breakdown Structure

Project Wireless Parking Meter WBS Code 1Cost$1322204-29-200607- 20-2006Project ManagerNadeem Ahmad

Subproject Subproject Subproject Transmission Reception GUI WBS Code WBS Code WBS Code 1.1Cost$140004-29-200605- 1.2Cost$180005-10-200606- 1.3Cost$120005-15-200607- 20-2006Subproject 20-2006Subproject 01-2006Subproject ManagerHung Le ManagerNasir Malik ManagerNadeem Ahmad

Main Work Package Work Package Main Work Package Detection System Synchronizing Signal Computer Display WBS Code WBS Code WBS Code 1.1.1Cost$80004-29- 1.2.1Cost$80005-10- 1.3.1Cost$60004-27- 200605-05-2006Subproject 200605-25-2006Subproject 200607-01-2006Subproject ManagerHung Le ManagerNasir Malik ManagerNadeem Ahmad

Work Package Work Package Application Coding Database System WBS Code WBS Code 1.3.1.1Cost$25005-01- 1.3.1.2Cost$35005-01- 200607-01-2006Subproject 200607-01-2006Subproject ManagerNadeem Ahmad ManagerNadeem Ahmad

Work Package Work Package Sensors Timer WBS Code WBS Code 1.1.1.1Cost$6004-29- 1.1.1.2Cost$4004-29- 200605-05-2006Subproject 200605-03-2006Subproject ManagerHung Le ManagerHung Le

29 As the project deliverables could be seen broken down into different sub-task, the project is divided into 3 major sections. When the transmission section will be done, we will be able to detect an illegally parked vehicle at any parking spot, take the parking spot ID where the car is parked and transmit it wirelessly. Transmission has two work packages. First is to design a network of sensors to detect the car at any specific parking spot and the second package is the timer to simulate the parking meter. Second subproject only has one work package which is to receive the signal with all the data of the illegally parked car sent by the transmitter and forward it to the computer using serial port. Final subproject is related to the computer display to the end user and this will represent the core interest of the end user in using the whole product. All the parking spots with their ID numbers will be added to a database with the location of that specific parking spot. The second package, which is more of an end product, will take in all the data from the receiver via serial port, sort it, and display it in user friendly manner. Package 1.3.1.2 will be of most interest to the end user and delivery date of this finished product is anticipated to be 07-01-2006. 1. Signal Transmission  Buy sensors  Buy Encoders  Prepare the PC Board  Buy Transmitter  Buy other Logic Design circuitry  Simulate Parking Meter  Simulate a few parking spots with toy cars 2. Signal Reception  Design noise filter  Determine the ranges  Buy Receiver  Attach Antenna with proper direction  Connect all the circuitry to PC using serial port 3. GUI Display  Decide and install the RAD language for coding  Install the editor necessary libraries  Buy serial to USB connector  Design database system  Code the application  Test the software

D. Project Milestones

The first point of interest for us is to finalize all the details for the project and buy all the required parts. Even though, this seems pretty trivial task, experience has proven to us that in many cases, most time spent on any subproject turns out to be getting the right parts. Parts are sometimes defective or sometimes not compatible with the product or simply not according to the requirement. The second very important goal is to successfully design and implement the detection circuitry. Since this circuit could be isolated and test very easily, this would the first major testing and feedback point for our project. Reception, synchronization and input of the signal to the computer, seems shortest on the papers but our general feeling is that this may turn out to be the hardest 30 part. Achieving all the assigned goals at this point will be a major success for the team since almost all the hardware section of the project will be achieved by getting to this point successfully. Last and probably most tedious subsection will be the software coding, which could sometimes be irritating and unpredictable. There are two major tasks involved in the software section i.e. database system and GUI for reading the serial port and displaying the results. Since this is the last portion of the project, it will the most important point of interest.

E. Gantt Chart

# Task Start Days End User May June July August 0 0 0 0 0 1 0 0 0 1 0 1 2 3 1 2 3 1 2 3 1 2 ------1 0 1 1 1 1 1 1 1 1 1 1 2 1 2 1 2 1

1 Research May-1 60 Aug-7 All x x x x > Logic Circuitry May-5 7 May-12 All x x x at Transmitter > Detection May-6 10 May-13 Hung x x x Circuitry. > Timer Circuit May-6 1 May-13 Nasir x x x 2 Transmission May-15 21 May-29 All x x x x x Hardware > Receiver June-7 25 June- All x x x Hardware 30 > Sorting ID July-01 7 July-08 Nadeem x x x Mech. > Graphical User July-21 30 Aug-01 Nadeem x x x Interface 3 Signal Sync. July-22 7 July-29 Nasir x x x x > Receiver July-29 7 Aug-01 All x x > Section Aug-1 2 Aug-04 Hung x x Integrations > End User Aug-3 1 Aug-4 All x x Interface 4 Test Aug-07 7 Aug-14 All x x 5 Documents Aug-10 100 Aug-17 All x x x x x x x x x x x Gantt Chart

F. Result Evaluation

It is one of the most important parts of the whole project since this will be the point where the project will have to work real-time regardless of its feasibility in theoretical yield. All the paper work and schematics end here and the final product will have to in working shape at this point. To test the project, we will actually use toy cars to simulate the real car parking and park them on specific spots. Instead of using dozens of cars, we will use switches or any dummy obstacle for the sensors to detect the car and 31 report. All the angles of parking will be tested and all the different combinations of occupied and empty spots will be tested as well. Performance of the software will be tested we will make sure that not only all the results are reported properly, but they are also correct and results are easy for the end user to understand for the end user.

VI. Ethical Considerations and Social Impact

C. Ethical Background: Parking played a vital row in our everyday life. More cars mean bigger parking lots and bigger parking lots mean more effort to keep discipline and control in parking lots. Today, there are many type of parking system, some of which consisting of a garage type of parking. This type of garage system allow the a vehicle to enter in and out through a gate, where there is at least one attendant who job is to issuing parking ticket as well as collecting fee for the used of the parking. This type of parking garage requires huge construction, where the cost can be extremely high in which lead to higher fee in parking. Another widely used method is a parking garage with meters. The cost for these meter are not high and can be implemented anywhere in the metropolitan without the need of huge construction. However, this system requires the parking attendants to physically check every parking meter for parking violation. Therefore, ours system is a system that used the principle of the preexisting parking meter but the function is differ in the sense that it alert the attendant when and where there is the violation. Ethical dilemma arises for choosing one of these two options. First option is not very desirable for the owner of the commercial parking garage where owner have to pay a lot of money to build the parking lot or pay lease or rent plus maintaining charges. Adding labor cost to it makes it worse for the owner. So having less labor cost by adopting the autonomous system we are designing will be desirable for the parking garage owner who could then reduce all the cost of paying his employee and profit margin will increase significantly for him. On the other hand, by reducing labor cost and autonomous control of parking garage will cause unemployment in parking attendants on individual bases and in general, it will be a part of another “machine replacing human” phenomenon for entire population. Loosing job for parking attendant or security officer has more direct negative effects on personal bases than on whole since generally “machine replacing human” phenomena’s also reduce the cost services in most cases.

D. Recognizing the Stakeholders The stakeholders for this device are the parking garage owner and parking attendants. Garage owners have to spend huge amount of money to hire parking attendants to control parking garage, which reduces their profits. On the other hand, parking attendants are employed on this expense and replacing the existing way in place would cause unemployment. General public is also affected in positive and negative way. Positive effect is the possible reduced cost in parking services and negative is higher employment rate.

E. Determining the Options

32  Best Extreme: Not firing any parking attendant and installing the system as well to make meter inspection process faster and easier for the attendant.

 Worst Extreme: Eliminating all parking attendants and make the whole parking autonomously controlled.

F. Compromise between Extremes Effective parking meter required only few parking attendants (one or two at most). Cost of operating the parking garage will be reduced in the benefit of parking garage owner and all of the parking attendants won’t loose jobs. So the compromise will be to install the system and not make it 100% autonomous (at all the points where cost-benefit analysis of the portion is not worth spending all the money and replacing parking attendant. For example, it is possible to scan the tag number of the illegally parked car and send the ticket to the person’s home address (which removes all needs of any parking attendant). However, this extra stretch will be very costly since it requires image recognition and processing at many spots in a parking garage and would probably be not worth replacing it for the parking attendant at the current technology level. So the compromise would be to have one parking attendant and install the system.

G. Application of Ethical Theories Utilitarianism theory supports the compromise, because it would generate the greatest benefit for the greatest number of people. It will help in making the parking services cheaper for whole public and garage owner’s profit will also go up. The compromise help secure the job of some parking attendant, where the worst extreme case will eliminate the job of all parking attendants. Even though our compromise doesn’t benefit all stake holders, it is beneficial for greatest number of people with more benefit than negative effect. The Ethical Egoism theory supports the compromise, from the perspective of the garage owner since there is nothing to loose for him and even though it can be argued, this theory is also support the point of view of parking attendant since autonomous system will do best for his company where he works. The Social Contract theory supports the Best extreme because it enhances the development of technology as well as provides efficiency in urbanized parking garage.

H. Choose, Defend, and Justify the Best Option Based on the Analysis Above. Based on the above analysis, the compromise is the system that is supported by the most ethical models. If we were to be implementing any of the models separately, then the compromise would be the best solution. Since the efficient parking meter will provide a better method of identifying the violator as well as assisting in the prosecution of the violator, yet this system will be cheap and more reliable to implement and reduces cost of services on almost all parts we think that hiring one or two parking attendants helped by the autonomous system is the best option.

VII. Multidisciplinary Aspects

33 We are a team of three with Hung Le with an electrical engineering major and Nasir Malik, and Nadeem Ahmad with computer engineering majors. All three members have different background in terms of experience and a wide range of knowledge in specific areas. Hung Le’s minor is in Power and he is very proficient in power systems and circuit designs. Hung will be helping the group in all the aspects of hardware and electrical circuitry and network. Hung will also be useful in the final component and system integration. Nasir’s areas of expertise are software engineering and design aspects of software system using UML design methodology. Nasir is also good at hardwired implementation of digital circuits. Nadeem’s focus will be on the programming part of the microcontroller and interfacing. Nadeem specializes in Object oriented programming, microprocessor interfacing, digital electronics, and signal processing. Nadeem also have practical knowledge of graphical user interfacing in XML and .NET. Nadeem will also be helping developing the application to display the result on the computer in a user friendly fashion.

VIII. Personnel

Name: Hung Le Education: Pursuing B.S. in Electrical Engineering (Senior) at Florida International University Specialized: Power Engineering Extra Skills: Matlab, PSPICE, AUTOCAD Awards Member of national society of collegiate scholar Member of Tau Beta Pi

Name: Nasir Malik Education: Pursuing B.S. in Computer Engineering (Senior) at Florida International University Specialized: Software Engineering Extra Skills: Java, UML, Matlab, PSPICE Awards: Recipient of Florida Bright Futures Scholarship

Name: Nadeem Ahmad Education: Pursuing B.S. in Computer Engineering (Senior) at Florida International University Specialized: Object Oriented Programming & Signal Processing Extra Skills: Java, C++, Scheme, VB.NET, Dreamweaver, Fireworks, HTML, PSPICE, MATLAB Honors and Full Tuition Scholarship (2000 till graduation) Awards: Completed 18 credits in honors at Miami Dade Valedictorian and recognized as the best graduate Medal of Honor for the Best graduate Most outstanding student for the term 97/98-2 Best Student in English Department Best Student in Math Department Work Software Developer at BrokerBuddy Inc. Experience:

34 IX. BUDGET (Variable at the time)

Parts Cost

Product Name Qty Cost Encoder chips 10 10 Misc. Logic Design Circuitry - 10 Transmitter 1 $50.00 28015 Sensors 6 $30.00 Javelin Microcontroller 1 $110 PNA4601M Infrared Receiver 3 $12 Parts Total $222

Labor Cost

Labor Cost Individual Salary Hours (Approx) Total $20.00/hr 100 $2000 $20.00/hr 100 $2000 $20.00/hr 100 $2000

Labor Total $6,000

Others

Instructor’ Salary $100/hr, $1200 4hrs/month, 3 months Fringe Benefit 20% x 10000 $2000 Lab Space 1000/month 3 $3000 months Lab Equipment 200/month 4 $800 months Total $7000 Total

Final Cost = Parts Total + Labor Total: $13,222

X. Conclusion

35 The project, at this point, seems to be cost effective and feasible in all terms. We have already ordered some basic parts for the project and we are testing those project for any defects of incompatibilities. We will be adding to this section as our project proceeds and we come up with any new findings.

XI. References

1. http://faculty.eng.fiu.edu/~arellano/4010.htm 2. http://www.uspto.gov/ 3. http://en.wikipedia.org/wiki/Intellectual_property 4. “ IEEE Standards Description”, (March 7, 2005), M.V. Rodriguez http://standards.ieee.org/reading/ieee/std_public/description/emc/ 5. https://courses.ece.uiuc.edu/ece445/?g=Home&p=Projects

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