Location based services are rapidly expanding. Outdoor location technologies are mainly based on GPS technologies. GPS does not perform properly indoors, and is not adequate; recently, as a result, indoor location systems are appearing on the market.
The need for a system such as ours stems from various market segments and applications. One example, in the market for integrated positioning and navigation systems using GPS receivers as their primary positioning technology, is the “Car navigator”.
However, a major limitation of GPS is that uninterrupted satellite reception is not possible in many situations. Densely populated areas and radio-frequency-signal shadowed locations, such as urban centers (“urban canyons”), generally do not allow proper operation of GPS, yet it is in these locations that the need is greatest.
There is a clear need for a cost effective system that maintains performance indoors, in urban canyons and in city centers.
Another important issue, GPS itself is susceptible to jamming and other man-made interference.
Description of GPS System.
The Global Positioning System (GPS) is a satellite-based navigation and time transfer system developed by the U.S. Department of Defense. GPS serves marine, airborne and terrestrial users, both military and civilian. Specifically, GPS includes the Standard Positioning Service (SPS) that provides civilian users with 100 meter accuracy as to the location or position of the user. It also serves military users with the Precise Positioning Service that provides 20-meter accuracy for the user. Both of these services are available worldwide with no requirement for any local equipment.
View of GPS Limitations:
First limitation of GPS is that upon activation the GPS receiver scans for signals from the GPS satellites. The unit must locate and receive signals from at least four satellites to be able to determine its location. This process of locating the satellites, receiving the data and achieving a position fix can take several minutes. This delay can be problematic for many GPS applications.
Second limitation of GPS is that the receiver needs a clear view of the sky to successfully receive signals from the satellites, again under unfriendly RF conditions such as inside buildings, or in “urban canyons” or under shadows of high buildings, the GPS suffers from multi-path effects and therefore shows poor performance, or none at all.
Third Limitation—limited accuracy: There's a problem of limited accuracy of civilian GPS signal. While knowing your position to within 50-200 feet anywhere on the planet is a major technological feat, it's still not accurate enough, to locate and navigate to an empty parking space, where each space measures about 10 feet, and most parking garages are located where the GPS is cannot work effectively.
Most of the navigation systems, such as the in-car navigation system, are based on GPS and have the aforementioned limitations.
Another significant factor adding to the limitations of the GPS based systems is the important role of map production; it is obvious that the user, driver, requires a map to be as detailed and as up-to-date as possible. However the existing maps used by the GPS based systems provide limited detail and the changes are not reflected on a timely basis
In this modern age when urban development is exploding, the lack of details and updates of the topographic maps and satellite images is critical; additionally and importantly, indoor location maps are not available at all for the GPS navigation systems.
Application:
In general, our system is based of applying machine-learning techniques to the task of inferring aspects of the user's state from a stream of input from sensors.
We have focused on indoor navigation, or navigation in crowded urban areas, where GPS based systems, due to lack of access to satellites or the GPS limitations detailed previously, cannot achieve the required results.
We have focused on the task of interactively guiding the user to a desired indoor destination.
Our system has a minimal need to know the user's location to carry out this task.
Examples of Indoor Applications:
The user may be looking for a certain store in a shopping mall, or a particular aisle in a department store.
The user may be looking for a certain conference room in a convention center, for a point of interest in an amusement park or for a point of interest in a museum.
The user may be looking for a train location in a station, or stops in a large subway or underground train station.
Or may just want to find available parking space.
Parking Detection and Navigation Application:
There is no easy way to find empty parking spaces in a busy city. Drivers usually either wastes time driving around the area looking for an open space, or abandons the search, paying a large fee to park in a garage, or to use a valet parking service. It would be very advantageous to be able to provide a driver looking for a parking space with Parking Detector, capable of identifying available, empty parking spaces in the driver's proximity, and with a competitive edge over someone without such a Parking Detector.
Every working day 105 Million drivers are looking for a place to park!
It is estimated that 40% of urban traffic is due to this “Search for parking a space.”
The top 85 US cities face increasing congestion problems because of steady population growth and the lack of locations to build additional parking. Traffic congestion is estimated to cost travelers in the 85 biggest US cities a whopping 3.5 billion hours a year, more than 50 hours a year per driver in major cities, almost a week of work.
Traffic and traffic congestion are two main reasons for pollution, and vehicle emissions contribute significantly to the “green house effect”.
In our society where time, convenience and comfort are precious commodities, parking is a major perk, or major headache.
Our “Parking Detection System” provides the answer to the most demanding need of any driver, “Where can I park?”
With the implementation of our system, navigating and detecting available parking spaces will become part of the information revolution.
Our system, a network of self organizing sensors will enable municipalities and other parking authorities to easily identify, exploit and manage revenue opportunities while at the same time providing better service at a lower operating cost.
With our system, drivers will save time, reduce the frustration of hunting for parking spaces and also will save money on gas usage and car maintenance costs.
By using and modifying existing technology, our system will integrate easily with other transportation and communication systems.
Reference to Prior Arts:
Despite the problems encountered by vehicle operators at parking facilities, most existing parking monitoring systems focus on collecting information for management. Some prior art systems employ sensors at entrances and exits to parking facilities or sections of such facilities (See U.S. Pat. No. 3,130,298 to Schwarz). These sensors trigger a counter to determine the number of cars in the monitored area by subtracting the number of cars leaving the area from those that have entered. At least one of these monitoring systems also engages a timer to determine the aggregate usage time of the facility by summing the total time from the entry of the cars to their departure (See U.S. Pat. No. 3,867,615 to Sioufi). These systems profess to be useful in monitoring the usage of the parking facility.
Prior Art curbside parking monitoring systems have been coupled with centralized signals which indicate general areas where drivers may find a curbside parking space (See U.S. Pat. Nos. 3,114,128 and 3,166,732 to Ljungman). Upon sensing that a space adjacent a parking meter is vacant, the system signals drivers from a signpost at an intersection of the city block along which the parking space is vacant. The signal appears in a binary yes or no stating that one or more parking spaces are available in the adjacent block-long area. However, because the driver seeing a parking available signal is not advised of the number and specific location of parking spaces that are available in that block, the vehicle operator may proceed to the indicated location to find that a single available space has already been occupied or that the space will not accommodate his vehicle. In either situation, the binary availability signal may lead the vehicle operator on a fruitless quest.
Another monitoring system for a parking facility compares the number of cars within a designated area (determined by counting cars entering minus cars departing the area) with the number of spaces within that area. When the net number of cars equals the number of spaces, the system registers that the area is completely full and signals drivers to proceed to the next area (See U.S. Pat. No. 3,158,836 to McCauley). Unfortunately, such systems again only yield a binary yes or no signal to the drivers. Even if an area contains only one available space, even if the space is obstructed, will not accommodate the driver's car, or is otherwise undesirable, a driver still will be lead to that area.
These prior art systems are of only limited help to vehicle operators and do not resolve many concerns associated with parking an automobile.
U.S. Pat. No. 5,293,163 to Kakihara, et al., entitled, “Navigation Apparatus for Vehicles”, describes a system for finding garages or other parking facilities with available parking spaces. It provides for the display of available parking information in map format. This vehicle navigational system patent does not address the problem of locating available on-street parking. Instead, it addresses the problem of locating parking lots with available spaces. Parking lots in congested city areas are not very cost effective, and they may not be in close proximity to the driver's destination. The patent does not direct drivers directly to an available metered space, a less expensive alternative, but simply to a large parking lot where they will have to search for an available space. In addition, the Kakihara map display only directs the driver as far as a parking facility. The driver still must navigate around the parking facility to locate an available space.
U.S. Pat. No. 5,432,508 to Jackson, entitled, “Technique for Facilitating and Monitoring Vehicle Parking”, describes a scheme for finding available parking spaces in garages and other parking facilities. It provides for the display of available parking information at the entrance of a garage and makes a provision for a light source to be mounted above a parking space to indicate its availability. Remote access to the data is provided by a dial-up telecommunication interface. Because the technique described operates over a wireline medium, it does not lend itself to being easily deployed in a wide area. Also, because parking information is never provided to any device within a vehicle, drivers still need to navigate through a garage to locate available spaces.
Parking meters with sensors, parking meters with transmitters, and navigational equipment receiving and displaying external information are well known in the art. U.S. Pat. No. 5,442,348 entitled, “Computerized Parking Meter”, for example, describes a parking meter utilizing an ultrasonic transducer to detect when a car is occupying a parking space. Similarly, U.S. Pat. No. 5,454,461, entitled, “Electronic Parking Meter and System”, describes a parking meter utilizing a sonar transducer for parked vehicle detection and radio means for receiving billing information.
At present, there is no on-board vehicle navigational system that delivers accurate and real time parking space information directly from the vehicle or ether portable phone application upon entering a specific geographic area.
Accurate Navigation
U.S. Pat. No. 5,504,482 to Schreder describes an automobile equipped with an inertial and satellite navigation system as well as a local area digitized street map. The main use of this patent is for route guidance in the presence of traffic jams, etc. Schreder describes how information as to the state of the traffic on a highway can be transmitted and utilized by a properly equipped vehicle to change the route the driver would take in going to his destination. Schreder does not disclose sub-meter vehicle location accuracy determination
Vehicle Location
U.S. Pat. No. 5,272,483 to Kato describes an automobile navigation system. This invention attempts to correct for the inaccuracies in the GPS system through the use of an inertial guidance, geomagnetic sensor, or vehicle crank shaft speed sensor. However, it is unclear as to whether the second position system is actually more accurate than the GPS system. This combined system, however, cannot be used for sub-meter positioning of an automobile.
U.S. Pat. No. 5,383,127 to Shibata uses map matching algorithms to correct for errors in the GPS navigational system to provide a more accurate indication of where the vehicle is or, in particular, on what road the vehicle is. This procedure does not give sub-meter accuracy. Its main purpose is for navigation and, in particular, in determining the road on which the vehicle is traveling.
U.S. Pat. No. 5,416,712 to Geier, et al. relates generally to navigation systems and more specifically to global positioning systems that use dead reckoning apparatus to fill in as backup during periods of GPS shadowing such as occur amongst obstacles, e.g., tall buildings in large cities. This patent shows a method of optimally combining the information available from GPS even when less than 3 or 4 satellites are available with information from a low-cost, inertial gyro, having errors that range from 1-5%. This patent provides an excellent analysis of how to use a modified Kalman filter to optimally use the available information.
U.S. Pat. No. 5,606,506 to Kyrtsos provides a good background of the GPS satellite system. It discloses a method for improving the accuracy of the GPS system using an inertial guidance system. This is based on the fact that the GPS signals used by Kyrtsos do not contain a differential correction and the selective access feature is on Locating a vacant parking space is an ordeal that causes frustration for many commuters. Even if a commuter pays to enter a parking lot, valuable time is consumed searching for a parking space within the parking lot. It seems that parking lots that service hospitals, airports, mass transit stations, entertainment forums, shopping malls and the like are always the most crowded, when time is the most crucial. As urban and suburban regions become more populated, finding a vacant parking space will become increasingly difficult for commuters.
U.S. Pat. No. 5,910,782 to Schmitt et al. ('782 patent) discloses a system for finding available on-street parking using an on-board vehicle navigation system and parking meters equipped with sensing devices. According to the '782 patent, real time metered parking space information can be accessed from a central location or directly by a vehicle, upon entering a specific geographic area.
U.S. Pat. No. 5,940,481 to Zeitman ('481 patent) discloses a parking management control system used to report parking, monitor parking and reserve parking spaces. According to the '481 patent, a user reports parking in a particular parking facility to a central control unit using a personal non-dedicated mobile communications device. The central control unit then confirms whether parking in the particular parking facility is authorized or not. The central control unit also generates a report indicating which parking facilities are supposed to be vacant for law enforcement officials so that unauthorized parking can be ticketed. The '481 patent also discloses that a user can reserve a desired parking facility by selecting a desired parking facility from a map provided from the central control unit. If a potential user, other than the registered user, communicates a request to park in the reserved parking facility, the control unit transmits a response to the potential user indicating that the parking facility is reserved and not authorized for use.
At present, however, no prior art device utilizes the capabilities to display a real-time representation of available parking spaces directly from the sensors without central system. And without using a GPS system directly to the “user” driver. Also most of them are for the parking garage or solutions to parking meters area when our system is for any places designate as parking space, ether in-door, out door, public or private. Our system based on sensors that detect the empty space where most of the other detect the car.
Other depends on a request to be sent to a central system or a database for parking where our system is a direct parking detector from the sensors.
Again, most of the existing prior arts are base ether on a GPS system or ether the existing car navigator (depend on a GPS to), and the existing mapping that they use has the same limitation as describe before and therefore practically can't be implements and work.
We believe that interface to the Internet can be a solution only for a remote planning and not a local solution where the driver is looking for a parking NOW!
We believe that our system method bridge the gap between the GPS based navigation and the existing system and allow to a complete solution.
Project in Parking:
XM Radio in conjunction with partners NU-Metrics inc. and infoGation, introduce a “parkingLink” capability concept.
The system shows the actual number of spaces available at designated parking facilities on vehicle navigation map, and uses color-keyed icons to indicate the percentage availability of the facility. The driver still must navigate around and inside the parking facility to locate an available space.
Parkingcarma from ACME Innovation, that is based on sensors that count the cars driving in and out of the parking facility and inform drivers via a cell phone call, or by an electronic sign, or over the internet, regarding the availability in the parking garage. The driver still must navigate around and inside the parking facility to locate an available space.
Other parking projects exist but they do not approach our innovation in ability to deliver a complete solution to the parking problem. Other projects address the issue from the perspective of a parking garage and do not consider street parking, nor are they really concerned to facilitate the location of an empty space inside their garage. They do not provide the driver with the ability to compare prices in the vicinity. Nor do other projects contemplate the concept of a parking detector with a direct communication between the sensors and the “user” driver in real-time#
Indoor Location Technologies
Various technologies are used for wireless indoor location. These may be classified in two aspects: The algorithm, i.e. the method of location used and the physical layer, i.e. the wireless technology used to communicate with the mobile device.
Location Methods
The methods typically used in indoor location are “borrowed” from the outdoor GPS location methods inventory. Specifically, four types of methods are used indoor:
Proximity Detection (PD), Received Signal Strength (RSSI), Time of arrival (TOA), and Angle of Arrival (AOA).
Proximity Detection (PD)
This method relies upon a dense grid of antennas, each having a well-known position. When a mobile is somehow detected by a single antenna, it is considered to be collocated with it. When more than one antenna detects the mobile, it is considered to be collocated with the one that receives the strongest signal.
This method is relatively simple to implement. It can be implemented over different types of physical media. In particular, IR and RFID are based on this method.
Triangulation
Triangulation takes PD a step further, in the sense that it is based on measuring the signal level measurements from each antenna (possibly by using a triangulation mechanism), with respect to each mobile device. Following that, mobile is located by using a triangulation algorithm. Like the PD method, triangulation is relatively simple to implement.
Time of Arrival (TOA)
TOA is based on triggering the mobile devices to respond, and measuring the time it takes for the response to flyback to the antenna. The elapsed time represents the distance between the two. By using distances from few antennas, a mobile's position can be triangulated. TOA considered to be the most accurate method, because multipath effects can be filtered out, Yet, it is considerably more complex to implement, as it requires a modified hardware on the mobile side, as well as special modifications on the antenna side.
Angle of Arrival (AOA)
AOA is based on finding the direction of maximal signal intensity for each antenna-device pair. By finding the intersection of few such direction vectors, a mobile's position can be estimated AOA is considerably less accurate than TOA, due to limited angular resolution and the fact that indoor much of the signal is reflected. Also, AOA antennas are more complex, as they require multi-section, highly directional antennas, and multiple RF circuitry.
WLAN (IEEE 802.11b)
This midrange wireless local networking standard, operating in the 2.4 GHz ISM band, has become very popular in public hotspots and enterprise locations during the last few years. With a typical gross bit rate of 11 Mbps and a range of 50-100 m, IEEE 802.11b is currently the dominant local wireless networking standard. It is therefore appealing to use an existing WLAN infrastructure for indoor location as well, by adding a location server. Such solutions do exist in the market, providing an accuracy of about 2 m. One limitation of such systems is the fact that WLAN tags are relatively bulky and power hungry. Thus, such locators are mainly useful to locate WLAN enabled instruments, such as portable computers.
Note that in WLAN, antennas are actually part of access points (APs), through which devices communicate with the access network. This is also the case with Bluetooth.
Bluetooth (IEEE 802.15)
Bluetooth is a newer wireless local networking standard, that operates in the 2.4 GHz ISM band. Compared to WLAN, the gross bit rate is lower (1 Mbps), and the range is shorter (typically 10-15 m, though there are Tags with a range of over 300 feet). On the other hand, Bluetooth is a “lighter” standard, highly ubiquitous (embedded in most phones, PDA's, PC peripherals, etc.) and supports, in addition to IP, several other networking services. Notably, Bluetooth supports serial port emulation, voice, and various types of object exchange.
Bluetooth tags are small, pocketsize transceivers.
Every Bluetooth device's tag has a unique ID. This ID can be used for locating the tag.