# US 2019/0174464 A1 · Method for controlling c-ran > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0174464 A1 - Document ID: US20190174464A1 - Status: Published application - Kind: A1 - Application number: 15/854,958 - Filed: 2017-12-27 - Published: 2019-06-06 - Earliest claimed: 2017-12-05 - Assignees: Industrial Technology Research Institute - Applicants: Industrial Technology Research Institute - Inventors: Jen-Feng HUANG - Web page: https://patentgrep.com/patent/US20190174464A1 ## CPC - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04W 72/51: based on terminal or device properties - H04W 72/52: based on load - H04W 88/085: {Access point devices with remote components} - H04W 74/002: {Transmission of channel access control information} - H04W 74/004: {in the uplink, i.e. towards network} - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A method for controlling C-RAN applicable for a C-RAN having a plurality of remote radio heads (RRH) and a baseband unit (BBU) includes the following steps: collecting a first uplink signal corresponding to a first user end device, determining a first estimated region based on a communication range of part of RRH's receiving the first uplink signal, setting N estimated coordinates in the first estimated region wherein N is larger than one, giving N moving directions to the N estimated coordinates, modifying the N estimated coordinates based on a maximum displacement and the N moving directions, and selecting at least one RRH to send a type-3 downlink packet to the first user end device based on the N modified estimated coordinates. ## Claims ### Claim 1 A method for controlling C-RAN, applicable for a C-RAN having a plurality of remote radio heads and a baseband unit, wherein the method comprises: receiving a plurality of preambles from the plurality of remote radio heads wherein each of the preambles is corresponding to one user end device; determining at least one type-2 downlink packet based on the plurality of preambles and the plurality of remote radio heads; if the at least one type-2 downlink packet is a plurality of type-2 downlink packets, determining whether a number of resource blocks of a physical downlink control channel is enough or not based on an amount of control signals of the plurality of type-2 downlink packets; and if the number of resource blocks is not enough, integrating at least part of the plurality of type-2 downlink packets based on a remote radio head arrangement table; wherein the remote radio head arrangement table is used for describing a relationship between geometric locations of the plurality of remote radio heads. ### Claim 2 (depends on 1) The method in claim 1, further comprising: collecting at least one first uplink signal corresponding to a first user end device; determining a first estimated region based on a communication range of part of the plurality of remote radio heads receiving the at least one first uplink signal; setting N estimated coordinates in the first estimated region, wherein N is an integer larger than one; giving N moving directions to the N estimated coordinates; modifying the N estimated coordinates based on a maximum displacement and the N moving directions; and selecting at least one remote radio head among the plurality of remote radio heads based on the N modified estimated coordinates to send a type-3 downlink packet to the first user end device. ### Claim 3 (depends on 2) The method in claim 2, further comprising determining a second estimated region and a third estimated region based on the communication range of part of the plurality of remote radio heads receiving the at least one first uplink signal and a communication range of part of the plurality of remote radio heads not receiving the at least one first uplink signal, wherein the second estimated region and the third estimated region are mutually exclusive and the first estimated region consists of the second estimated region and the third estimated region. ### Claim 4 (depends on 2) The method in claim 2, further comprising: determining a covering set based on the N modified estimated coordinates, wherein the covering set includes at least one second remote radio head among the plurality of remote radio heads; and receiving an uplink packet of the first user end device or monitoring a second uplink signal of the first user end device by the at least one second remote radio head. ### Claim 5 (depends on 4) The method in claim 4, wherein the covering set includes a minimum covering set and a maximum covering set, and the minimum covering set is a set comprising the least of the plurality of remote radio heads to cover the N modified estimated coordinates, and the maximum covering set is a set comprising all remote radio heads capable of communicating with at least one among the N modified estimated coordinates. ### Claim 6 (depends on 5) The method in claim 5, further comprising using the at least one second remote radio head corresponding to the minimum covering set to receive the uplink packet. ### Claim 7 (depends on 4) The method in claim 4, further comprising: updating the first estimated region based on a communication range of part of the plurality of remote radio heads receiving the second uplink signal; selectively removing part of the N modified estimated coordinates based on the updated first estimated region; and adding at least one estimated coordinate so as to keep an amount of the modified estimated coordinates as N. ### Claim 8 (depends on 1) The method in claim 1, further comprising controlling part of the plurality of remote radio heads receiving the plurality of preambles to receive a third message. ### Claim 9 A method for controlling C-RAN having a plurality of remote radio heads and a baseband unit, comprising: collecting at least one first uplink signal corresponding to a first user end device; determining a first estimated region based on a communication range of part of the plurality of remote radio heads receiving the at least one first uplink signal; setting N estimated coordinates in the first estimated region, wherein N is an integer larger than one; giving N moving directions to the N estimated coordinates; modifying the N estimated coordinates based on a maximum displacement and the N moving directions; and selecting at least one remote radio head among the plurality of remote radio heads based on the N modified estimated coordinates to send a type-3 downlink packet to the first user end device. ### Claim 10 (depends on 9) The method in claim 9, further comprising determining a second estimated region and a third estimated region based on the communication range of part of the plurality of remote radio heads receiving the at least one first uplink signal and a communication range of part of the plurality of remote radio heads not receiving the at least one first uplink signal, wherein the second estimated region and the third estimated region are mutually exclusive and the first estimated region consists of the second estimated region and the third estimated region. ### Claim 11 (depends on 9) The method in claim 9, further comprising: determining a covering set based on the N modified estimated coordinates, wherein the covering set includes at least one second remote radio head among the plurality of remote radio heads; and receiving an uplink packet of the first user end device or monitoring a second uplink signal of the first user end device by the at least one second remote radio head. ### Claim 12 (depends on 11) The method in claim 11, wherein the covering set includes a minimum covering set and a maximum covering set, and the minimum covering set is a set comprising the least of the plurality of remote radio heads to cover the N modified estimated coordinates, and the maximum covering set is a set comprising all remote radio heads capable of communicating with at least one among the N modified estimated coordinates. ### Claim 13 (depends on 12) The method in claim 12, further comprising using the at least one second remote radio head corresponding to the minimum covering set to receive the uplink packet. ### Claim 14 (depends on 11) The method in claim 11, further comprising: updating the first estimated region based on a communication range of part of the plurality of remote radio heads receiving the second uplink signal; selectively removing part of the N modified estimated coordinates based on the updated first estimated region; and adding at least one estimated coordinate so as to keep an amount of the modified estimated coordinates as N. ### Claim 15 (depends on 9) The method in claim 9, further comprising: receiving a plurality of preambles from the plurality of remote radio heads wherein each of the preambles is corresponding to one user end device; determining at least one type-2 downlink packet based on the plurality of preambles and the plurality of remote radio heads; if the at least one type-2 downlink packet is a plurality of type-2 downlink packets, determining whether a number of resource blocks of a physical downlink control channel is enough or not based on an amount of control signals of the plurality of type-2 downlink packets; and if the number of resource blocks is not enough, integrating at least part of the plurality of type-2 downlink packets based on a remote radio head arrangement table; wherein the remote radio head arrangement table is used for describing a relationship between geometric locations of the plurality of remote radio heads. ### Claim 16 (depends on 15) The method in claim 15, further comprising controlling part of the plurality of remote radio heads receiving the plurality of preambles to receive a third message.