# US 2019/0246288 A1 · Spectrum sharing between primary users and co-existence groups of secondary users > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0246288 A1 - Document ID: US20190246288A1 - Status: Published application - Kind: A1 - Application number: 16/385,432 - Filed: 2019-04-16 - Published: 2019-08-08 - Earliest claimed: 2017-02-22 - Assignees: Federated Wireless, Inc. - Applicants: Federated Wireless, Inc. - Inventors: Samuel J. MacMULLAN; Masoud OLFAT; Deepak DAS; Pirouz ZARRINKHAT - Web page: https://patentgrep.com/patent/US20190246288A1 ## CPC - H04W 16/14: Spectrum sharing arrangements {between different networks} - H04B 17/102: {Power radiated at antenna} - H04W 16/18: Network planning tools - H04W 52/243: {taking into account interferences} - H04W 52/367: {Power values between minimum and maximum limits, e.g. dynamic range} - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04W 72/51: based on terminal or device properties - H04W 72/541: using the level of interference - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04B: TRANSMISSION ## Abstract Embodiments assign shared spectrum resources to access points. Embodiments group the access points into coexistence groups of access points, and generate a vertex graph including vertices that each represent one of the coexistence groups, where an edge connecting a pair of vertices in the vertex graph represents an overlap between coverage contours of a pair of coexistence groups represented by the pair of vertices, and the edge is assigned a weight that is proportional to the overlap as compared to other overlaps between coverage contours of other pairs of coexistence groups. Embodiments generate at least one vertex-colored graph by assigning a color to each vertex in the vertex graph, group the coexistence groups into groups of coexistence groups based on their corresponding assigned colors in the at least one vertex-colored graph, and map shared spectrum transmit frequencies to the groups of coexistence groups. ## Claims ### Claim at position 1 1-23. (canceled) ### Claim 24 A method for assigning shared spectrum resources to access points, comprising: grouping the access points into coexistence groups of access points; generating a vertex graph including vertices that each represent one of the coexistence groups, wherein a connection in the vertex graph between a pair of the vertices representing a pair of the coexistence groups is assigned a weight based on an amount of interference between the pair of the coexistence groups; generating at least one vertex-colored graph by assigning a color to each vertex in the vertex graph; grouping the coexistence groups into groups of coexistence groups based on their corresponding assigned colors in the at least one vertex-colored graph; and mapping shared spectrum transmit frequencies to the groups of coexistence groups, wherein each access point in a group of coexistence groups is configured to transmit using a transmit frequency that is assigned to the group of coexistence groups by the mapping. ### Claim 25 (depends on 24) The method of claim 24, wherein the mapping of the shared spectrum transmit frequencies to the groups of coexistence groups is performed based on an objective function, the method further comprising: assigning a transmit power level to each access point using the at least one vertex-colored graph along with the objective function. ### Claim 26 (depends on 25) The method of claim 25, wherein the objective function has objective parameters including access point bandwidth and coverage areas, wherein the objective function increases as the objective parameters increase. ### Claim 27 (depends on 25) The method of claim 25, wherein the objective function has cost parameters including interference costs and switching costs, wherein the objective function decreases as the cost parameters increase, wherein the switching cost is indicative of a negative impact of a candidate assignment requiring an access point to change transmit frequency or power, wherein the interference costs depend at least partly on weights assigned to the connections in the at least one vertex-colored graph. ### Claim 28 (depends on 25) The method of claim 25, wherein the objective function accounts for constraints including minimum access point bandwidth, minimum access point transmit power, incumbent protection, or guard bands between access point frequency assignments. ### Claim 29 (depends on 24) The method of claim 24, wherein the method is performed by at least one Spectrum Access System (SAS) implemented as one or more software modules on a cloud platform. ### Claim 30 (depends on 24) The method of claim 24, wherein the method is performed by coordination of at least two Spectrum Access Systems (SASs) that share information to generate the at least one vertex-colored graph, wherein the SASs use the at least one vertex-colored graph along with a single common objective function to assign frequency and transmit power levels to access points, wherein the shared information includes the weights of the connections in the at least one vertex-colored graph. ### Claim 31 (depends on 24) The method of claim 24, wherein all coexistence groups in a same group of coexistence groups have a same assigned color in the at least one vertex-colored graph, wherein no connection of the at least one vertex-colored graph is connecting two vertices that have a same assigned color. ### Claim 32 (depends on 24) The method of claim 24, wherein the vertices are colored using graph coloring. ### Claim 33 (depends on 24) The method of claim 24, wherein the vertex graph comprises two or more connected sets, wherein vertices in each connected set are colored independently of other connected sets to generate two or more vertex-colored graphs, wherein the grouping of the coexistence groups is performed separately on each of the two or more vertex-colored graphs. ### Claim 34 (depends on 33) The method of claim 33, wherein the mapping of the shared spectrum transmit frequencies to the groups of coexistence groups is performed based on an objective function, the method further comprising: in each connected set, assigning a transmit power level to each access point using a corresponding vertex-colored graph along with the objective function. ### Claim 35 (depends on 33) The method of claim 33, wherein the two or more connected sets are created by applying at least one cut on the vertex graph, wherein the at least one cut is a minimum cut of the vertex graph along a set of the connections with a lowest aggregate connection weight. ### Claim 36 (depends on 25) The method of claim 25, wherein the at least one vertex-colored graph is used along with the objective function to maximize bandwidth and coverage area of the access points while minimizing interference to locations in a protected area. ### Claim 37 (depends on 25) The method of claim 25, wherein the at least one vertex-colored graph is used along with the objective function to maximize bandwidth and coverage area of the access points while minimizing interference to an incumbent device. ### Claim 38 (depends on 25) The method of claim 25, wherein the at least one vertex-colored graph is used along with the objective function to maximize bandwidth and coverage area of the access points without minimizing interference to an incumbent device. ### Claim 39 (depends on 38) The method of claim 38, wherein, after maximizing bandwidth and coverage area of the access points without minimizing interference to an incumbent device, access point transmit power levels are adjusted to minimize an aggregate interference to an incumbent device. ### Claim 40 (depends on 39) The method of claim 39, wherein the access point transmit power levels are adjusted by applying a fairness criterion. ### Claim 41 (depends on 40) The method of claim 40, wherein the access point transmit power levels are further adjusted by: after applying the fairness criterion, determining a leftover margin on the aggregate interference to the incumbent device; reassigning the leftover margin to access points. ### Claim 42 (depends on 41) The method of claim 41, wherein the access point transmit power levels are further adjusted by: determining Effective Isotropic Radiated Power (EIRP) deficits for each access point based on access point requested transmit power levels and the power determined by applying the fairness criterion; and applying a level of reverse water filling of power over the access points such that: (A) the EIRP deficit after the reverse water filling is the same for all access points, and (B) the resulting aggregate interference increase at the incumbent device after the reverse water filling is less than or equal to the leftover margin. ### Claim 43 A non-transitory computer-readable medium storing instructions that, when executed by a processor, cause the processor to assign shared spectrum resources to access points, the assigning comprising: grouping the access points into coexistence groups of access points; calculating an amount of interference between the coexistence groups; generating a vertex graph including vertices that each represent one of the coexistence groups, wherein a connection in the vertex graph between a pair of the vertices representing a pair of the coexistence groups is assigned a weight based on an amount of interference between the pair of the coexistence groups; generating at least one vertex-colored graph by assigning a color to each vertex in the vertex graph; grouping the coexistence groups into groups of coexistence groups based on their corresponding assigned colors in the at least one vertex-colored graph; and mapping shared spectrum transmit frequencies to the groups of coexistence groups, wherein each access point in a group of coexistence groups is configured to transmit using a transmit frequency that is assigned to the group of coexistence groups by the mapping. ### Claim 44 A network system, comprising: one or more servers; and two or more Spectrum Access Systems (SASs) implemented as software modules hosted on the one or more servers, wherein the two or more SASs are configured to communicate with each other and with access points to assign shared spectrum resources to the access points, the assigning comprising: grouping the access points into coexistence groups of access points; calculating an amount of interference between the coexistence groups; generating a vertex graph including vertices that each represent one of the coexistence groups, wherein a connection in the vertex graph between a pair of the vertices representing a pair of the coexistence groups is assigned a weight based on an amount of interference between the pair of the coexistence groups; generating at least one vertex-colored graph by assigning a color to each vertex in the vertex graph; grouping the coexistence groups into groups of coexistence groups based on their corresponding assigned colors in the at least one vertex-colored graph; and mapping shared spectrum transmit frequencies to the groups of coexistence groups, wherein each access point in a group of coexistence groups is configured to transmit using a transmit frequency that is assigned to the group of coexistence groups by the mapping. ### Claim 45 (depends on 44) The network system of claim 44, wherein the weight assigned to the connection between the pair of the coexistence groups is further based on a comparison of the interference between the pair of the coexistence groups as against an amount of interference between another pair of the coexistence groups. ### Claim 46 (depends on 43) The non-transitory computer-readable medium of claim 43, wherein the weight assigned to the connection between the pair of the coexistence groups is further based on a comparison of the interference between the pair of the coexistence groups as against an amount of interference between another pair of the coexistence groups. ### Claim 47 (depends on 24) The method of claim 24, wherein the weight assigned to the connection between the pair of the coexistence groups is further based on a comparison of the interference between the pair of the coexistence groups as against an amount of interference between another pair of the coexistence groups.