# US 9,439,201 B2 · Interference cancellation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,439,201 B2 - Document ID: US9439201B2 - Status: Granted - Kind: B2 - Application number: 14/350,173 - Filed: 2011-10-07 - Published: 2015-07-23 - Granted: 2016-09-06 - Earliest claimed: 2011-10-07 - Assignees: Telefonaktiebolaget LM Ericsson (publ) - Applicants: Torbjörn Wigren - Inventors: Torbjörn Wigren - Web page: https://patentgrep.com/patent/US9439201B2 ## CPC - H04W 72/52: based on load - H04B 15/00: Suppression or limitation of noise or interference (by means associated with receiver H04B1/10) - H04J 13/00: Code division multiplex systems (for frequency hopping H04B1/713) - H04W 24/02: Arrangements for optimising operational condition - H04W 72/21: in the uplink direction of a wireless link, i.e. towards the network - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04B: TRANSMISSION - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) ## Abstract A radio base station and a method therein for scheduling an uplink radio resource to a first user equipment in a wireless communication system which employs CDMA are provided. The method comprises measuring an Interference Cancellation, IC, gain for each user equipment in a set of user equipments currently being served by the radio base station. The method further comprises determining a user constellation pertaining to information regarding the different user equipments in the set of user equipments and their respective bitrates; and updating a table of IC gain with the measured IC gain in bins corresponding to the determined user constellation. The method further comprises predicting a load based on at least the updated table, and scheduling the uplink radio resource to the first user equipment at least partly based on the predicted load. ## Claims ### Claim 1 A method in a radio base station for scheduling an uplink radio resource to a first user equipment in a wireless communication system which employs Code Division Multiple Access (CDMA) the method, performed by the radio base station, comprising: receiving, at a receiving circuit of the radio base station, a plurality of signals from a set of user equipments currently being served by the radio base station in the wireless communication system, measuring an Interference Cancellation (IC) gain for each user equipment in the set of user equipments currently being served by the radio base station, wherein the IC comprises canceling an interference within the plurality of signals received at the receiving circuit of the base station by processing respective ones of the plurality of received signals based on a measurement by the radio base station of at least one of the plurality of signals received at the receiving circuit of the radio base station, determining a user constellation pertaining to information regarding different user equipments in said set of user equipments and their respective bitrates, selecting a bin of a plurality of bins in an IC gain table responsive to the determined user constellation, wherein the plurality of bins correspond to different user constellations, updating the IC gain table with the measured IC gain in the selected bin, predicting a load based on said updated IC gain table, and scheduling the uplink radio resource to the first user equipment at least partly based on said predicted load. ### Claim 2 (depends on 1) The method according to claim 1, wherein measuring the IC gain for the set of user equipments comprises measuring an air interface load as seen after IC processing and an air interface load before IC processing. ### Claim 3 (depends on 2) The method according to claim 2, wherein of the air interface load is measured as rise over thermal (RoT). ### Claim 4 (depends on 3) The method of claim 3, wherein the IC gain is the difference between the air interface load before the IC processing and the air interface load as seen after the IC processing. ### Claim 5 (depends on 3) The method according to claim 3, further comprising transforming said RoT after the IC processing and said RoT before the IC processing to load factors. ### Claim 6 (depends on 5) The method according to claim 5, wherein said IC gain is determined by determining a load factor difference between the air interface load before and after the IC processing. ### Claim 7 (depends on 1) The method according to claim 1, wherein determining the user constellation comprises measuring Transport Format Combination Indicator (TFCI) and Enhanced-TFCI (E-TFCI) used by user equipments in the set of user equipments. ### Claim 8 (depends on 1) The method according to claim 1, further comprising tabulating and averaging the IC gain as a function of at least a subset of the user constellation. ### Claim 9 (depends on 1) The method according to claim 1, wherein said scheduling the uplink radio resource to the first user equipment comprises scheduling radio resources in Wideband Code Division Multiple Access (WCDMA) Enhanced Uplink (EUL). ### Claim 10 (depends on 1) The method according to claim 1, wherein said scheduling the uplink radio resource to the first user equipment comprises scheduling radio resources in Time Division Multiplexing (TDM) uplink. ### Claim 11 A radio base station configured to schedule an uplink radio resource to a first user equipment in a wireless communication system which employs Code Division Multiple Access (CDMA) the radio base station comprising: a receiving circuit configured to receive a plurality of signals from a set of user equipments currently being served by the radio base station in the wireless communication system, at least one processor; and memory coupled to the at least one processor and comprising computer readable program code embodied in the memory that when executed by the at least one processor configures the processor to: measure an Interference Cancellation (IC) gain for each user equipment in the set of user equipments currently being served by the radio base station, wherein the IC comprises canceling an interference within the plurality of signals received at the receiving circuit of the base station by processing respective ones of the plurality of received signals based on a measurement by the radio base station of at least one of the plurality of signals received at the receiving circuit of the radio base station, determine a user constellation pertaining to information regarding different user equipments in said set of user equipments and their respective bitrates, select a bin of a plurality of bins in an IC gain table responsive to the determined user constellation, wherein the plurality of bins correspond to different user constellations, update the IC gain table with the measured IC gain in the selected bin, predict a load based on said updated IC gain table, and schedule the uplink radio resource to the first user equipment at least partly based on said predicted load. ### Claim 12 (depends on 11) The radio base station according to claim 11, wherein the at least one processor is configured to measure the IC gain for the set of user equipments by measuring an air interface load as seen after IC processing and an air interface load before IC processing. ### Claim 13 (depends on 12) The radio base station according to claim 12, wherein the air interface load is measured as rise over thermal (RoT). ### Claim 14 (depends on 13) The radio base station according to claim 13, wherein the IC gain is the difference between the air interface load before IC processing and the air interface load as seen after IC processing. ### Claim 15 (depends on 13) The radio base station according to claim 13, wherein the at least one processor is further configured to transform said RoT after the IC processing and said RoT before the IC processing to load factors. ### Claim 16 (depends on 15) The radio base station according to claim 15, wherein the adapted at least one processor is further configured to determine said IC gain by determining a load factor difference between the air interface load before and after the IC processing. ### Claim 17 (depends on 11) The radio base station according to claim 11, wherein the at least one processor is configured to measure Transport Format Combination Indicator (TFCI) and Enhanced-TFCI (E-TFCI) used by user equipments in the set of user equipments and wherein the processor is further configured to determine a user constellation based on the measured TFCI and E-TFCI used by user equipments in the set of user equipments. ### Claim 18 (depends on 11) The radio base station according to claim 11, wherein the at least one processor is further configured to tabulate and average the IC gain as a function of at least a subset of the user constellation. ### Claim 19 (depends on 11) The radio base station according to claim 11, wherein the at least one processor is configured to schedule the uplink radio resource to the first user equipment by scheduling radio resources in Wideband Code Division Multiple Access (WCDMA) Enhanced Uplink (EUL). ### Claim 20 (depends on 11) The radio base station according to claim 11, wherein the at least one processor is configured to schedule the uplink radio resource to the first user equipment by scheduling radio resources in Time Division Multiplexing (TDM) uplink.