Patent Application
20150124630
1. Technical Field
The present invention relates to a system for locating a Wi-Fi transmission device where the Wi-Fi transmission device does not have an integrated Global Positioning System (GPS). More particularly, the present invention relates to determining the position of a cable network node that provides Wi-Fi transmission to deliver communication signals, where the Wi-Fi transmission device does not have GPS.
2. Related Art
New Cable Wireless Nodes (e.g. Cable Wi-Fi and small cell nodes) that transmit Wi-Fi signals to display devices such as tablet computers, cell phones and wireless televisions have integrated GPS for automatic location identification (ALI). However, most of the current deployments around the world have older nodes without GPS. Some cable service providers aim to upgrade their wireless node deployments while others extend to new locations by keeping existing systems. Both managing existing systems and upgrading processes require accurate location identification of nodes. However, existing systems without GPS rely on manual physical location identification which is an error prone process. This results in losing equipment, additional onsite work and overall poor Fault, Configuration, Accounting, Performance and Security (FCAPS) management.
Service providers that supply the nodes, include cable television system providers, DSL providers, and fiber network providers that offer Wi-Fi access, for example in outdoor hotspots, shopping malls or airports where users can connect tablets, cell phones or computers. These service providers want cheaper versions of these nodes or Access Points (APs) including outdoor carrier Wi-Fi equipment, or other mobile indoor Wi-Fi. The service providers want to have an automatic way of getting AP's physical location information to assist with deployment and operations or for location based services, even while existing wireless deployments may not have integrated GPS to lower the cost. Furthermore GPS may not work well in some deployment scenarios such as indoor hotspots.
Most existing Hybrid Fiber Coaxial (HFC) network architectures maintain a separate wireless Network Management System (NMS). If both systems are managed together a two-fold gain is possible: 1) Wireless nodes with GPS or other Approximate Location Information (ALI) techniques may help to locate or validate the location of other HFC components; 2) HFC components with known location may help to locate or validate the location of wireless nodes. The latter is also helpful for cases where AP or 3G/4G node is not operational but CM is still reachable.
The above systems show that GPS is not always available or preferred and other ALI mechanism solutions that can provide approximate location information are needed. Non-GPS based solutions are desirable for service providers that already have deployments with Cable Wi-Fi nodes without GPS or are interested in low cost outdoor Wi-Fi nodes. Integration of wireless and cable with location information when GPS is not available in all systems may also be desired by service providers that want to have a unified monitoring and inventory system.
For older nodes that do not include GPS, embodiments of the present invention provide software based ALI identification solutions. The following, software based ALI solutions are provided using integration of wireless AP nodes into coaxial, HFC and other network architectures.
The software uses network segment identification, ranging and channel characteristics' analysis to locate the cable modem (CM) that is to be located is included in a network segment, or serving fiber node. If the serving fiber node is not known for the Cable Wi-Fi node, a first set of steps needed is to determine its network neighborhood. U.S. Pat. No. 7,742,697, describes these steps used to identify when CMs are connected to the same optical node by instructing two CMs, one with a known location and another with an unknown location to transmit at frequencies f1 and f2 to detect any intermodulation distortion at frequency f3 where intermodulation distortion would be expected when transmissions occur both at f1 and f2. If intermodulation is produced which exceeds a threshold, then the two CMs are determined to be in that network fiber node where measurement is made. Further steps in the method are then applied with steps of the '697 patent to determine the relative location of the unknown Wi-Fi CM node when the CMs, are co-located in the same network segment as described to follow.
First in the location determination method are steps provided when the fiber node location is known and includes ranging to estimation of the general location of the cable wireless node relative to the determined fiber node. If the location of the fiber node is known, a general location of the cable wireless node can be estimated relative to the fiber node. Otherwise, steps of ranging are applied with trilateration to determine the fiber node location. This method applies the steps of ranging and geometry of circles or triangles from location information of three or more CMs that are not aligned with the fiber node, so that the location of fiber node may be identified (this is the trilateration method). Using all this information, a general location of the cable wireless node can be estimated within a circular area. Then, using additional information that the operator may have (e.g. Cable Wi-Fi node is integrated in a tap) and measuring common channel characteristics (e.g. equalization characteristics) behind a network component in the same segment, the location of the Cable Wireless node may be more specifically identified.
A second method uses location approximation with transit delay. In this method the device's location from a headend node is measured using the transit delay from the node to the device such as an HFC node with a known location determined to be connected to the AP node. In the case of an HFC powered Wi-Fi AP, the location will need to be on the cable strand somewhere. For instance, if you know that the AP is at a certain distance from the node, there are only a finite number of actual locations it can be. In order to cheaply calculate transit delay, IEEE 1588v2 type software may be used to determine transit delay for ranging. In particular, consider a system in which the remote unit (an HFC-powered Wi-Fi AP, for example) uses 1588 to derive exact Time of Day (TOD). Then, the AP can be queried to transmit its exact time of day to the headend. When the packet arrives, the TOD in the packet can be compared to the actual TOD. The difference would be the one-way transit delay. This method can also be used for non-DOCSIS links.
A third method uses the location of a nearby home or SMB (Small Medium Business) gateway. This method takes into account that low-cost Cable Wi-Fi options will be located primarily nearby a large group of houses and businesses that may have Multiple Service Operator (MSO) gateways. If a nearby MSO home/SMB gateway can be used to get APs info with Cable Wi-Fi SSIDs, it can be used for approximate location identification since home gateways location will be known to MSOs.
A fourth method uses a nearby mobile device with GPS. Many mobile devices, such as mobile phones, have integrated GPS and many users enable location related features. Cable Wi-Fi APs are typically located at places where multiple mobile device users connect. Therefore, an AP can make connections with GPS enabled mobile devices, such as cell phones, shortly after the AP is up and during its operation. Mobile phones, as well as other devices such as tablet computers can have software that provides their location information to the corresponding service management platforms. MSOs can use specific client apps for their subscribers as well as roaming partner users. The location information at different partner MSOs' service management platforms may be shared. Note that, IEEE 802.11 has location request and reply messages as a part of standardization that can be used for location information exchange. Depending on the chips used, if these IEEE 802.11 messages are available they can also be used for location identification purposes.
A fifth method may be implemented by Wi-Fi system operators that may integrate the location information data with their Home Location Register/Home Subscriber Server databases. Most mobile devices have both 3G/4G and Wi-Fi connections. When Wi-Fi mobile devices are connected to the AP, they can use the database information to identify their location as well as provide GPS location data to update the AP location. In this case, the location information is obtained from the mobile core and provided to the MSO's Wi-Fi service management platform.
A combination of multiple ones of the above techniques may be implemented to locate or validate the location of wireless AP nodes and HFC components in the overall network architecture.
Further details of the present invention are explained with the help of the attached drawings in which:
For older nodes that do not include GPS, embodiments of the present invention provide software based ALI identification solutions.
Embodiments of the present invention enable an AP node such as 102, without built in location identification hardware, to determine location. The following, software based ALI solutions are provided using integration of wireless AP nodes into coaxial, HFC and other network architectures.
A first method uses network segment identification, ranging and channel characteristics' analysis in HFC node sites to locate the CM in the Cable Wi-Fi node. If the network segment, e.g. the serving fiber node, for the Cable Wi-Fi node has an unknown location, the first step is to determine its network neighborhood. For example, U.S. Pat. No. 7,742,697, assigned to General Instrument Corporation, describes a method to identify when Cable Modems (CMs) are connected to the same optical node by instructing two CMs to transmit at frequencies f1 and f2 to detect any intermodulation distortion in the laser at frequency f3 where intermodulation distortion would be expected when transmissions occur both at f1 and f2. If intermodulation is produced which exceeds a threshold, then the two CMs are determined to be connected to the same fiber node where measurement is made. The same technique can be used for location determination of a CM in a Cable Wireless node that is connected to a fiber node. For this purpose, the CM with known location (e.g. a CM inside a subscriber's home) will transmit at f1 while CM in a Cable Wireless node will transmit at f2.
Although the '697 patent enables determination if two CMs are connected to the same fiber node, the CMs specific location relative to the node is still unknown prior to step 212 of
In step 216, by measuring common channel characteristics behind a network component, the location of the Cable Wireless AP node may be more specifically identified. In step 218 a check is made to determine if a common channel characteristic identifies a tap. If so, the specific location is made, and control is sent to step 220 and the program ends. Otherwise, another set of CMs is selected in step 218 and control is sent to step 216 which is repeated for the new set of CMs. Measuring common channel characteristics in step 218 includes equalization characteristics to confirm that certain CMs are connected to the same tap. Note that based on a-priori information of the AP node's location, some steps of
An alternative method to locate the AP is to use transit delay to get an estimation of a device's location from a headend or plant node. A measurement is made of the transit delay from the node to the device such as a Cable Wi-Fi node with unknown location. In the case of an HFC powered Wi-Fi AP, the location will need to be on the cable strand somewhere. For instance, if you know that the AP is 1462 feet from the node, there are only a finite number of actual locations it can be. In order to cheaply calculate transit delay, IEEE 1588v2 type software may be used to determine transit delay. In particular, consider a system in which the remote unit (Wi-Fi AP, for example) uses 1588 to derive exact Time of Day (TOD). Then, the AP can be queried to transmit its exact time of day to the headend. When the packet arrives, the TOD in the packet can be compared to the actual TOD. The difference would be the one-way transit delay. This method can also be used for Wi-Fi nodes without DOCSIS backhaul, i.e. fiber Ethernet backhaul.
With or Without a HFC network environment, wireless node sites which have location information, including Wi-Fi devices with GPS, can be used to provide location. The following sections describe methods for determining location using wireless nodes.
Another method to locate an AP takes into account that low-cost Cable Wi-Fi options will be located primarily nearby a large group of houses and businesses that may have a Multiple Service Operator (MSO) home/SMB gateway. If a nearby MSO gateway can be used to get APs info with Cable Wi-Fi SSIDs, it can be used for approximate location identification since home gateways location will be known to MSOs. For this purpose, MSOs may have a common software implementation to have gateways and Cable Wi-Fi nodes to detect their SSIDs and unique identifiers to be processed for a database that combines indoor and outdoor nodes' information.
Many mobile devices, such as mobile phones, have integrated GPS and many users enable location related features. Cable Wi-Fi APs are typically located at places where multiple mobile device users connect. Therefore, an AP can make connections with GPS enabled mobile devices, such as cell phones, shortly after the AP is up and during its operation. Mobile phones, as well as other devices such as tablet computers can have software that provide their location information to the corresponding service management platforms. MSOs can use specific client apps for their subscribers as well as roaming partner users. The location information at different partner MSOs' service management platforms may be shared. Wi-Fi connection between the cable AP and the mobile device with GPS provides a way to get users' location information when the user is connected to an AP without a known location. Note that, IEEE 802.11 has location request and reply messages as a part of standardization that can be used for location information exchange. Depending on the chips used, if these IEEE 802.11 messages are available they can also be used for location identification purposes.
Accordingly, one embodiment of the present invention provides an algorithm that gets location information for the AP or one of the CMs is by obtaining it though a Wi-Fi connection between the cable AP and a user's mobile device that has an accurate location to use to get the user's location information to identify the AP's location. Software may be specific to the Wi-Fi service management platform or can be an open platform. For example, an application may use location identification services Application Program Interfaces (APIs) when users consent to cable Wi-Fi terms (users may opt out).
Another method is where Wi-Fi system operators may integrate the location information obtained with embodiments of the present invention with their Business Intelligence software as a proprietary software option. Telco and Mobile Virtual Network Operator (MVNO) and other service providers that support mobile device networks can integrate the location data with their Home Location Register/Home Subscriber Server (HLR/HSS) databases (for example during the EAP-SIM/AKA processing which is a mechanism for authentication and session key generation using a mobile device network where user credentials are used for Wi-Fi connection). Most mobile devices have both 3G/4G and Wi-Fi connections, so EAP-SIM/AKA type solutions may be used to include user location for cable and telco hotspots. Thus, when Wi-Fi mobile devices are connected to the AP, MSOs' service management platforms can be integrated with mobile core to extract users' location and use this information to identify AP node's location.
The above location solutions, including HFC solutions in section A and wireless solutions in section B, can be combined. Combined solutions are described in the following sections.
A combination of multiple ones of the above techniques may be implemented to locate or validate the location of wireless AP nodes and HFC components in the overall network architecture. For example, if the AP wireless link is broken, the location can be verified by using HFC node site. On the other hand, if a Cable Wi-Fi AP node location is determined based on nearby mobile devices with GPS according to the present invention and is connected to a tap with other HFC components having an unknown location, by using common channel characteristics other HFC components location may be validated.
Both HFC and Wireless domain information and techniques may be combined to create a unified database of cable nodes including traditional HFC components and Cable Wi-Fi nodes in the plant. Such a unified approach improves overall FCAPS management and bandwidth and power allocation. Prior to storage of location in a unified database, several rules may be accessed to determine if the location information is accurate enough. One such rule is to only get location information from mobile nodes with integrated GPS and home gateways. Such a rule increases the confidence level for the physical registration obtained. The algorithm or method can set the location information based on multiple inputs from multiple users with mobile devices close to the AP at startup. Then when there is a big change, such as an indication that the AP is moved, as indicated based on confidence levels that may be determined by the number of inputs, the AP location can be updated and also validated by using HFC domain information.
