System and method for private wireless networks

A method and system for private wireless network communications is provided. A private wireless network controller is coupled to a Private Branch Exchange (PBX), a private base transceiver station, and a Public Switched Telephone Network (PSTN). The private base transceiver station is coupled to a wireless macro network. The private wireless network controller and private base transceiver station allow connection of interconnect and dispatch wireless calls, which originate on the private wireless network, to other mobile stations on the private wireless network, to terminals connected to the PBX, to mobile stations on wireless macro networks, and to terminals coupled to the PSTN.

BACKGROUND OF THE INVENTION

Companies and other organizations rely upon mobile stations for their employees to remain accessible regardless of their location. A mobile station can be any type of wireless communication device including wireless telephones, wireless Personal Digital Assistants (PDA), wireless pagers, or any device which performs one or more of these functions. This accessibility applies to both travel away from the company's office and the ability to communicate within the office. While in the office employees may use a mobile station to receive telephone calls or electronic mail when they are not near their desktop telephone or computer.

Increased usage of wireless communications by companies has resulted in increasing bills for such wireless communications. To reduce costs for wireless communications which originate or terminate within a company's premises, some companies have installed private wireless networks to avoid paying wireless carriers for airtime for such communications. These private wireless networks typically are independent of wireless service providers' macro networks, expensive to implement, and do not provide a number of features which would be desired by businesses.

Some private wireless networks operate using communication protocols which are not typically employed by major wireless carriers on their macro networks. For example, some companies have attempted to implement private wireless networks which operate using Voice over wireless Internet Protocol (IP). While one advantage of using wireless protocols which are not compatible with protocols used by major wireless carriers is that the company does not have to be concerned with receiving charges for airtime usage on wireless macro networks, the use of incompatible protocols reduces the flexibility provided to the business. Specifically, if an employee is authorized to communicate within both a private wireless network and wireless macro network, the employee would be required to have two different mobile stations, each with a different telephone number. This is particularly inconvenient as such an arrangement requires the employee to carry two mobile stations while within the company's premises so that calls to either telephone number can be received. Additionally, this may result in the employee having two separate voicemail systems, one for each wireless network. Moreover, if an employee initiates a telephone call within the private wireless network and travels to an area outside of the private wireless network, the employee's telephone call will be dropped because the mobile station does not use the same protocols as wireless macro networks.

Accordingly, there is a need for a system and method of providing wireless communications over both publicly-accessible and private wireless networks.

SUMMARY OF THE INVENTION

A private wireless network includes a private wireless network controller and a private base transceiver station for supporting interconnect and dispatch wireless communications. The private wireless network controller and the private base transceiver station can route communications between the private wireless network, a private wired network such as a Private Branch Exchange (PBX) network, a wireless macro network, and a Public Switched Telephone Network (PSTN).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1illustrates an exemplary communication system which allows a subscriber of a private wireless network to communicate over either the private wireless network or a wireless macro network. The system illustrated inFIG. 1is divided into a private communication network101and publicly-accessible communication networks102. The private communication network can cover one or more buildings (such as a “campus” of a building for a company), a single floor, or a portion of a floor occupied by a company. The private communications network101includes a private wireless network including a private base transceiver station (BTS)104, antennas106A and106B and private wireless network controller108. The private communications network101also includes a Local Area Network (LAN)110, a Private Branch eXchange (PBX)112, one or more PBX phones114, and one or more wireless phones116A and116B. The publicly-accessible communication networks102include the Internet120, a wireless macro network122and a Public Switched Telephone Network (PSTN)124.

The private wireless network controller108provides wireless communications for mobile stations116A and116B in conjunction with private BTS104and antennas106A and106B. Mobile stations116A and116B can include circuitry and/or software for operating according to a protocol compatible with a wireless macro network (e.g., digital advanced mobile telephone service (D-AMPS), time division multiple access (TDMA), code division multiple access (CDMA), integrated enhanced dispatch network (iDEN), global system for mobile communication (GSM), or the like), a protocol compatible only with the private wireless network (e.g., using WiFi and voice over wireless IP, or the like), or a combination of wireless macro network and private wireless network protocols (with the mobile station selecting which protocol to use for communicating). Mobile station116A can communicate with destinations which are part of the private communication network's telephone system, such as PBX phone114, using private wireless network controller's connection to PBX112. Moreover, private wireless network controller108can provide wireless communications between mobile stations116A and116B. Using the private wireless network controller108, the mobile stations116A and116B can also communicate over the Internet120(via LAN110), the wireless macro network122(via private BTS104) or the PSTN124(via PBX112).

AlthoughFIG. 1illustrates the private wireless network controller coupled to a single wireless macro network122, the private wireless network controller108can be coupled to more than one wireless macro network. This connection may involve a separate private wireless network controller for each wireless macro network. Moreover, communications can occur with subscribers located in other wireless macro networks which do not have an interface with the private wireless network controller108by routing the communications over the PSTN124.

The private wireless network controller108can provide mobile stations operating on the private wireless network with the same functionality and restrictions typically associated with PBX networks. For example, the private wireless network controller108can provide mobile stations operating on the private wireless network with abbreviated number dialing (such as four digit dialing), toll restrictions, billing code entry and the like.

FIG. 2illustrates a block diagram of an exemplary communication system which allows mobile stations in a private wireless network to initiate and receive interconnect and dispatch communications with communications devices outside of the private wireless network.FIG. 2includes a private communication network201and wireless macro network202. For purposes of explanation, and not limitation, the illustrated wireless macro network is based upon an iDEN communications system such as that owned and operated by Nextel Communications, Inc. of Reston, Va. However, the wireless macro network202can be any type of wireless communication system such as one that operates in accordance with TDMA, CDMA, GSM, D-AMPS, or any other wireless communication protocol. The wireless macro network202includes at least one wireless antenna204, an enhanced BTS (EBTS)206, a Digital Access Cross-connect Switch (DACS)208, an interconnect and circuit-switched processing portion210, and a packet data processing portion212. If the wireless macro network is not an iDEN network, then the private wireless network controller will be coupled to the Base Site Controller (BSC)214.

The antenna204and EBTS206transmit and receive wireless communications with mobile stations (not shown) within the wireless macro network202. The EBTS206provides communications which are received over antenna204to DACS208. Depending upon the type of communications, DACS208routes the communications to either the interconnect and circuit-switched processing portion210or the packet data processing portion212. Interconnect communication is what is conventionally considered “cellular communications” and are handled in a conventional manner by interconnect and circuit-switched processing portion210. Specifically, interconnect and circuit-switched processing portion210includes a BSC214and a Mobile Switching Center (MSC)216. MSC216can have a connection to a Short Message Service (SMS) processor218and a voicemail processor220. MSC216transmits and receives communications between the wireless macro network202and the PSTN222.

Packet Data Processing Portion212includes a Metro Packet Switch (MPS)224and a Dispatch Application Processor (DAP)226. The Packet Data Processing Portion212is coupled to the Internet230via Mobile Data Gateway (MDG)228. The packet data processing portion212processes both computer-type packet data and dispatch call data. A dispatch call is commonly known as a walkie-talkie or push-to-talk (PTT) type of call such as Nextel's service identified by the trade name Direct Connect.

Dispatch calls are routed based upon a Universal Fleet Member Identifier (UFMI). The UFMI is composed of a series of numbers which represent an Urban ID, Fleet ID, and Member ID. An Urban ID corresponds to a location area where a subscriber's information can be found. Typically, an Urban ID is associated with each DAP, which generally covers a city. Due to the number of digits in the Urban ID there can only be a limited number of DAPs provisioned in a wireless macro network. If the components of the wireless macro network202were provisioned on each private communication network201then the growth of the wireless macro network would be limited by the number of private wireless networks202, and likewise the number of private wireless networks201would be limited by the number of DAPs in the wireless macro network. Accordingly, it would be desirable to provision the private wireless networks201without requiring a new Urban ID for each private wireless network201.

In accordance with exemplary embodiments, dispatch call processing is provided for private wireless networks201without using new Urban IDs. Specifically, the private wireless network controller232is coupled to the DACS208of the wireless macro network202, thereby allowing dispatch and interconnect calls to be routed through the wireless macro network202to other subscribers of the wireless macro network without requiring new Urban IDs. The private wireless network, by appearing as another BTS to the wireless macro network, does not require a new Urban ID.

Alternatively, if there are a sufficient number of available Urban IDs in the wireless macro network, the private wireless network can be configured as its own location area. In an iDEN network this would include an interconnect location area (ILA) and a dispatch location area (DLA). Accordingly, the private wireless network would broadcast its location area identification which will cause mobile stations to perform location updates when they move into the coverage area of the private wireless network. The location updates would result in transferring of subscriber data for the mobile station from the wireless macro network to the private wireless network.

FIG. 3illustrates a block diagram of an exemplary private BTS302and private wireless network controller304. The private wireless network controller304includes a call router310, a Home Location Register/Visitor Location Register database (HLR/VLR)312, a dispatch call processor314, an interconnect call processor316, and a transcoder318.

The private BTS302includes a site controller306, such as an iDEN site controller (iSC), and a plurality of base radios (BR)308A-308C. The site controller operates in a similar manner to a macro network site controller, and can connect the base radios308A-308C to the antennas of the private wireless network.

The base radios can operate using the same or different protocols. For example, base radios308A and308B can provide voice over wireless IP communications while base radio308C can provide a wireless communications protocol which is compatible with a wireless macro network, such as GSM, CDMA, TDMA or iDEN wireless communications protocol. Providing a number of radios which operate in accordance with a number of different air interface protocols allows a company to provide dual-protocol compatible mobile stations to some employees who are authorized to make wireless telephone calls in both the private wireless network and the wireless macro network, while providing mobile stations which are only compatible with the private wireless network (e.g., which operate using voice over wireless IP protocols) to those employees who are only authorized to make wireless communications over the private wireless network. Alternatively, or additionally, employees who are authorized to make wireless telephone calls in both the private wireless network and the wireless macro network can have a mobile station which operates using the wireless macro network protocols.

Although illustrated inFIG. 3as separate elements, the functions of each of the elements of the private wireless network controller304can be performed by a single element such as a computer programmed to perform the functions. Additionally, the functions can be performed by a single element with hard-wired logic to perform these functions such as an Application Specific Integrated Circuit (ASIC), Field Programmable Gate-Array (FPGA), or the like. Moreover, the private BTS and the private wireless network controller304can be combined into a single unit. However, in order to maintain compatibility with the wireless macro network, the call router310should be connected to the macro network.

Call router310uses HLR/VLR312to determine whether the subscriber associated with the dialed number is located on the private wireless network, located at a voice terminal accessible by the PBX, located at a communication device accessible via the PSTN, or located within the wireless macro network. Specifically, the HLR/VLR312includes an identifier, such as a telephone number, for each destination located in the private network. The call router310compares an identifier in a call setup message with identifiers stored in the HLR/VLR312. If the identifier is not stored in the HLR/VLR312and the identifier has the proper formatting for a PSTN number, the call router310will route the call to the PSTN.

For dispatch calls, the call router310employs dispatch call processor314. The dispatch call processor314performs similar functions to those conventionally performed by a DAP in a wireless macro network. Similarly, for interconnect calls where the destination terminal is accessible either from the PBX or via the PSTN, call router310employs interconnect call processor316. Because the mobile station uses a particular type of coding for transmitting voice to the private wireless network, transcoder318changes the voice coding such that it is compatible with the voice coding used by the PBX or the PSTN, such as Pulse Code Modulation (PCM) coding.

For communications in which the destination communication device is accessible via the wireless macro network, the call router310routes the communication to the wireless macro network. If the voice coding of the communication received by the call router310is not compatible with the wireless macro network, the call router310can include transcoding functionality such that the communications are compatible with the wireless macro network. Similarly, if the voice coding of communications from the wireless macro network are not compatible with the communication devices of the private wireless network, the call router310can perform transcoding for communications destined for the private wireless network.

The system also includes a private network manager320which is coupled via a bus to all of the component of the private wireless network304. The private network manager320is used for provisioning users in the private network, setting call restrictions, and the like. The private network manager320can be a computer which is either operated directly by a user using its associated input device, or the private network manager can be a server which is accessible via a web browser for remotely accessing the functionality of the private network manager320.

FIG. 4illustrates an exemplary method for registering a subscriber of a private wireless network. A mobile station sends a registration request to the private wireless network (step405). The private wireless network determines whether mobile station has a subscription with the private wireless network (step410). If the mobile station does not have a subscription with the private wireless network (“No” path out of decision step410), then the processing described below in connection withFIG. 5is performed. If, however, the mobile station has a subscription with the private wireless network (“Yes” path out of decision step410), then the private wireless network marks the mobile station as present on the private wireless network in the local VLR (step415).

The private wireless network forwards the registration request message to the wireless macro network (step420) and waits for a response. Mobile stations which are authorized to operate on both the private wireless network and the wireless macro network will be provisioned in location databases in both the wireless macro network and the private wireless network. These mobile stations are assigned telephone numbers associated with the wireless macro network. Accordingly, telephone calls destined to these telephone numbers will be initially routed to the wireless macro network. Mobile stations which are not authorized to operate on the wireless macro network will be provisioned only in the location database of the private wireless network. These mobile stations will have telephone numbers associated with the PBX of the private communication network. Accordingly, telephone calls destined for these mobile stations will be routed to the PBX.

If the wireless macro network responds with a registration rejection message (“No” path out of decision step425), then the wireless private network modifies the registration rejection message (step430) and registers the mobile station on the private wireless network (step435). Accordingly, the mobile station will only be able to operate on the private wireless network, and will not be able to handoff onto the wireless macro network.

If, however, the wireless macro network responds with a registration successful message (“Yes” path out of decision step425), then the private wireless network forwards the registration successful message to the mobile station (step440). Because the mobile station is registered with the wireless macro network as being located on the private wireless network, the mobile station can handoff to base stations of the wireless macro network.

FIG. 5illustrates a flow diagram of an exemplary method for a mobile station which does not have a subscription with the private wireless network to attempt a registration with the private wireless network. When the private wireless network receives a registration request from a mobile station which does not have a subscription with the private wireless network, the private wireless network determines whether non-subscribers are allowed to register (step505). If non-subscribers are not allowed to register with the private wireless network (“No” path out of decision step505), then the private wireless network rejects the registration request (step510). If, however, the private wireless network allows registrations from non-subscribers (“Yes” path out of decision step505), then the private wireless network forwards the registration request to the wireless macro network (step515) and waits for a response from the wireless macro network.

If the wireless macro network registration attempt is not successful (“No” path out of decision step520), then the private wireless network forwards the registration rejection message to the mobile station. If, however, the wireless macro network registration is successful (“Yes” path out of decision step520), then the private wireless network forwards the registration confirmation message to the mobile station (step530).

FIG. 6is a flow diagram of an exemplary method for a private wireless network subscriber to make a call while located within the private wireless network. When a private wireless network subscriber dials a number (step605) the call is routed to the private wireless network controller (step610). The private wireless network controller determines, based upon the dialed number, whether the subscriber is allowed to make the call (step615). Whether the subscriber is allowed to make the call can depend upon a number of factors including whether the call is a toll call, whether the call is to be routed outside of the private wireless network, and the like. Additionally, although this method is described in connection with a dialed number and a call, it will be recognized that the method is equally applicable to a computer communication where a dialed number would correspond to, for example an electronic mail address and the call would correspond to the electronic mail. Likewise, this method is equally applicable to instant messaging type applications. If the subscriber is not allowed to make the call (“No” path out of decision step615), then the private wireless network controller terminates the call (step620).

If the subscriber is allowed to make the call (“Yes” path out of decision step615), the private wireless network controller then determines whether the destination associated with the dialed number is located on the private wireless network (step625). If the called party associated with the destination number is located on the private wireless network (“Yes” path out of decision step625), then the call controller routes the call through the private wireless network (step630). If the destination subscriber is not located on the private wireless network (“No” path out of decision step625), then the private wireless network controller determines whether the call is a dispatch call (step635).

If it is determined that the call is a dispatch call (“Yes” path out of decision step635), then the private wireless network controller routes the call to the wireless macro network (step640). If, however, the call is not a dispatch call (“No” path out of decision step635), then the private wireless network controller determines whether the call is a wireless interconnect call (step645). If the call is not a wireless interconnect call (“No” path out of decision step645), then the call is routed to the PSTN (step650). If the call is a wireless interconnect call (“Yes” path out of decision step645), then the call is routed to the wireless macro network (step655).

FIGS. 7A and 7Billustrate flow diagrams of an exemplary method of terminating a call to a subscriber of the private wireless network. When a caller dials a number of a private wireless network subscriber (step705), a determination of whether the called number is associated with the wireless macro network is performed (step710). This determination is a conventional call processing procedure in which an originating network consults call routing tables to determine a destination network. As discussed above, mobile stations which are authorized to operate on both the private and macro wireless networks will have a telephone number associated with the wireless macro network, while mobile stations which are authorized to operate only on the private wireless network will have a telephone number associated with the PBX. Accordingly, if the originating network determines that the dialed telephone number is associated with the wireless macro network (“Yes” path out of decision step710), then the call request is routed to the wireless macro network (step715).

The wireless macro network determines the currently registered location of the subscriber (step720). Specifically, the wireless macro network determines whether the subscriber is located on private wireless network by accessing a location database, e.g., an HLR, which indicates the location from which the private wireless network subscriber last registered. If the private wireless network subscriber is on the private wireless network (“Yes” path out of decision step720), then the private wireless network routes the call to the dialed subscriber's mobile station (step730). If the subscriber is not located on the private wireless network (“No” path out of decision step720), then the wireless macro network routes the call to the subscriber at the last registered location within the wireless macro network (step725).

If dialed telephone number is not associated with the wireless macro network, i.e., it is associated with the PBX of the private network (“No” path out of decision step710), then the call request is forwarded to the private network where it is determined whether the subscriber is currently located on the private wireless network (step735). If the subscriber is not currently registered on the private wireless network (“No” path out of decision step735), then the call is terminated (step740). Termination of the call can involve routing the call originator to a voicemail system associated with the dialed subscriber. If the subscriber is currently located on the private wireless network (“Yes” path out of decision step735), then the private wireless network routes the call to the subscriber.

The private wireless network disclosed herein can be implemented in a number of different ways. For example, a company can purchase the private wireless network equipment. In this case, the company will also have to maintain the equipment and pay fees to a wireless macro network operator for the connection to the wireless macro network. Alternatively, a wireless macro network operator can provide the private wireless network to the company. The company then pays the wireless macro network operator some type of fee. For example, the company can pay a per user fee for use of the private wireless network. Additionally, the company can pay an additional fee for particular mobile stations to operate on both the private and macro wireless networks. It will be recognized that a company may not pay for fees for all employees to operate on the wireless macro network. In this case, the wireless macro network operator can establish a separate account with the employee for usage of the wireless macro network. Accordingly, the wireless macro network operator would receive fees from the company for the employees use of the private wireless network, and fees from the employee for use of the macro wireless network. If the wireless macro network operator has roaming agreements with 802.11 hotspots, and if the subscriber's mobile station supports VoIP, then the wireless macro network operator can offer a plan which includes roaming to 802.11 hotspots.