Method and apparatus of dynamic spectrum sharing in cellular networks

Abstract

According to a disclosed method, an MME in a network analyzes KPIs from the cells it serves and based on the KPIs, it decides to engage in sharing. The MME then contacts a sharing entity (SE) to announce that it wants to supply spectrum for sharing. The MME obtains terms of a sharing agreement from the SE and the MME obtains the identity of the other network. In response to this information, the MME configures its base stations to support the supplying of spectrum to the other network. The SE applies knowledge of network topology and of services offered. This knowledge is obtained from a sharing database. At the expiration of the sharing agreement, the SE tells the MMEs to deactivate the sharing agreement.

We claim: 
     
         1 . A method performed by a digital processor, comprising:
 receiving computer-readable messages that announce sharing attempts from processors respectively connected to two or more networks having different operators, wherein each sharing attempt is an attempt to borrow or to supply spectrum;   retrieving information, from a computer-accessible database, that describes a topology of at least one wireless network and lists services offered by the network;   automatically brokering one or more sharing agreements between network operators using the retrieved information, wherein each sharing agreement specifies terms for the sharing of spectrum;   automatically providing to each of two or more operators, in the event that a sharing agreement is successfully brokered between them, a computer-readable message that describes the terms of the sharing agreement and that identifies the other operator or operators that are party to the sharing agreement; and   automatically notifying each operator that is party to the sharing agreement when the sharing agreement is expiring.   
     
     
         2 . The method of  claim 1 , wherein the brokering and providing steps comprise:
 receiving notification of a maximum permissible bandwidth for subleasing from a supply sector belonging to an operator willing to supply spectrum;   sending a subleased spectrum release request to the supply sector;   receiving notification of a spectrum release from the supply sector; and   sending notification, to a demand sector belonging to an operator wishing to borrow spectrum, that the released spectrum is available for the demand sector to use.   
     
     
         3 . Apparatus, comprising:
 a module configured to receive announcements of sharing attempts from processors respectively connected to two or more networks having different operators, wherein each sharing attempt is an attempt to borrow or to supply spectrum;   a module configured to retrieve information describing a topology of one or more wireless networks and listing services offered by the networks from a computer-accessible database;   a module configured to broker sharing agreements between network operators, using information retrieved from the database, wherein each sharing agreement specifies terms for the sharing of spectrum, and to provide to each of two or more operators, in the event that a sharing agreement is successfully brokered between them, the terms of the sharing agreement and the identities of the other operator or operators that are parties to the sharing agreement; and   a module configured to notify each operator that is a party to the sharing agreement when the sharing agreement is expiring.   
     
     
         4 . The apparatus of  claim 3 , wherein the brokering module is configured for:
 receiving notification of a maximum permissible bandwidth for subleasing from a supply sector belonging to an operator willing to supply spectrum;   sending a subleased spectrum release request to the supply sector;   receiving notification of a spectrum release from the supply sector; and   sending notification, to a demand sector belonging to an operator wishing to borrow spectrum, that the released spectrum is available for the demand sector to use.   
     
     
         5 . A method in a base station controlled by a home operator and serving mobile terminals in one or more sectors, comprising:
 receiving sharing instructions from a core network controlled by the home operator;   activating a sharing state in a selected one or more of the sectors in response to the sharing instructions; and   deactivating the sharing state when the sharing agreement expires or terminates, wherein:   the sharing instructions specify spectrum that is to be temporarily released or acquired by each of the selected one or more sectors; and   activating the sharing state in each said sector comprises:   configuring at least one software-defined programmable radiofrequency front end of the base station for operation on spectrum that is reconfigured due to the release of shared spectrum carriers; and   directing mobile terminals served by said one or more sectors to operate on the reconfigured spectrum.   
     
     
         6 . The method of  claim 5 , wherein:
 the sharing instructions specify spectrum that is to be temporarily released to one or more demand sectors that are controlled by a borrowing operator different from the home operator; and   activating the sharing state in each sector further comprises releasing specified carriers to the borrowing operator.   
     
     
         7 . The method of  claim 6 , wherein, for each of one or more supply sectors:
 the total spectrum allocated to said sector is partitioned between shared spectrum and unshared spectrum;   the sharing instructions identify one or more carriers belonging to the shared spectrum as released carriers; and   the mobile terminals are directed to migrate from released carriers onto one or more carriers that are unreleased from the shared spectrum or that belong to the unshared spectrum without service disruption.   
     
     
         8 . The method of  claim 7 , wherein, before configuring the software-defined programmable radiofrequency front end of the base station for operation on reconfigured spectrum, the base station performs the further step of:
 placing the mobile terminals of the carrier-releasing sector or sectors into a temporary Suspend state in which no user-plane or control-plane communication takes place between the mobile terminal and the base station or other elements of a radio access network.   
     
     
         9 . A base station apparatus, comprising:
 circuitry configured to provide sector-specific service to mobile terminals, in each of one or more respective sectors, that subscribe to at least a first operator;   circuitry configured to activate and deactivate a sharing state in one or more selected sectors in response to instructions received by the base station from a core network controlled by the first operator; and   for at least one sector, a software-defined programmable radiofrequency front end, wherein:   the sharing instructions specify spectrum that is to be temporarily released or acquired by each of the selected one or more sectors;   the front end is adaptable, in response to instructions from the activation and deactivation circuitry, to operate on spectrum that is reconfigured due to the release of shared spectrum carriers; and   the base station apparatus further comprises circuitry operative for directing mobile terminals served by one or more of said sectors to operate on the reconfigured spectrum.   
     
     
         10 . The apparatus of  claim 9 , wherein the activation and deactivation circuitry is responsive to the sharing instructions by temporarily releasing specified carriers to a second operator different from the first operator. 
     
     
         11 . The apparatus of  claim 10 , wherein, for each of one or more sectors:
 the activation and deactivation circuitry is responsive to a partition of the total spectrum allocated to said sector between shared spectrum and unshared spectrum;   the activation and deactivation circuitry is responsive to sharing instructions that identify one or more carriers belonging to the shared spectrum as released carriers; and   the directing circuitry is operative to migrate the mobile terminals from released carriers onto one or more carriers that are unreleased from the shared spectrum or that belong to the unshared spectrum without service disruption.   
     
     
         12 . The apparatus of  claim 11 , further comprising circuitry that is operative, before said configuration of the software-defined programmable radiofrequency front end, to place the mobile terminals of the carrier-releasing sector or sectors into a temporary Suspend state in which no user-plane or control-plane communication takes place between the mobile terminal and the base station or other elements of a radio access network. 
     
     
         13 . A method performed by a processor connected to a node of a wireless core network that controls at least one radio access network (RAN) and is operated by at least a first operator, comprising:
 obtaining key performance indicators (KPIs) from one or more cells served by the core network, wherein the KPIs include measurements of uplink and downlink Interference-over-Thermal (IoT);   deciding to make a sharing attempt based on the KPIs, wherein the sharing attempt is an attempt to borrow spectrum, and selecting favorable spectrum for sharing;   announcing the sharing attempt and the selected spectrum to a sharing entity (SE) embodied in a processor connected to the wireless core network;   obtaining from the SE the identity of at least one operator willing to supply spectrum and the terms of a sharing agreement with the further operator; and   configuring the RAN to support the borrowing of spectrum from the supplying operator according to the terms of the sharing agreement.   
     
     
         14 . The method of  claim 13 , further comprising:
 making a determination, based on the IoT measurements, whether there is too much interference to proceed with the borrowing attempt in at least one sector; and   in response to a determination that there is too much interference, configuring the RAN for reduced transmission power in at least one said sector.   
     
     
         15 . An apparatus comprising:
 a module configured for obtaining key performance indicators (KPIs) from one or more cells served by a wireless core network that controls at least one radio access network (RAN) and is operated by at least a first operator, wherein the KPIs include measurements of uplink and downlink Interference-over-Thermal (IoT);   a module configured for formulating attempts to share spectrum based on the KPIs, wherein the formulating includes selecting favorable spectrum for sharing;   a module configured for announcing sharing attempts to a sharing entity (SE) embodied in a processor connected to the wireless core network and for obtaining from the SE the identities of further operators and the terms of sharing agreements with the further operators, wherein the announcing of the sharing attempts includes indicating the selected spectrum; and   a module configured for configuring the RAN to support borrowing of spectrum from further operators and/or to support supplying of spectrum to further operators according to the terms of sharing agreements.   
     
     
         16 . The apparatus of  claim 15 , wherein:
 the module configured for formulating sharing attempts is further configured to determine, based on the IoT measurements, whether there is too much interference to proceed with the borrowing attempt in at least one sector; and   the module configured for configuring the RAN is adapted, in response to a determination that there is too much interference, to configure the RAN for reduced transmission power in at least one said sector.   
     
     
         17 . A method performed by a digital processor, comprising:
 receiving a computer-readable message, from a processor connected to a network, announcing an attempt by the network to borrow spectrum;   receiving, from a server, a computer-readable message announcing an attempt by an entity to supply whitespace or unlicensed spectrum;   retrieving information, from a computer-accessible database, that describes a topology of the borrowing network and lists services offered by the network;   automatically brokering one or more sharing agreements between the spectrum supply entity and an operator of the borrowing network using the retrieved information, wherein each sharing agreement specifies terms for the sharing of spectrum, and whereby said entity and said operator are made parties to the sharing agreement;   automatically providing to each of said parties, in the event that a sharing agreement is successfully brokered between them, a computer-readable message that describes the terms of the sharing agreement and that identifies each party to the other party; and   automatically notifying each party when the sharing agreement is expiring.