# US 2013/0157578 A1 · Apparatus and method for wireless communication via at least one of directional and omni-direction antennas > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0157578 A1 - Document ID: US20130157578A1 - Status: Published application - Kind: A1 - Application number: 13/768,117 - Filed: 2013-02-15 - Published: 2013-06-20 - Earliest claimed: 2006-06-06 - Assignees: QUALCOMM Incorporated - Inventors: Sanjiv Nanda; Saishankar Nandagopalan; Santosh Abraham; Jay Rodney Walton; Ernest T. Ozaki - Web page: https://patentgrep.com/patent/US20130157578A1 ## CPC - H04B 15/00: Suppression or limitation of noise or interference (by means associated with receiver H04B1/10) - H01Q 1/246: {specially adapted for base stations} - H01Q 3/24: varying the orientation by switching energy from one active radiating element to another, e.g. for beam switching - H04B 7/0602: {using antenna switching (H04B7/0686 takes precedence; antenna beam directivity switching H01Q3/24)} - H04W 28/18: Negotiating wireless communication parameters - H04B 7/0615: {of weighted versions of same signal} - H04B 7/0842: {Weighted combining} - H04W 16/28: using beam steering - H04B: TRANSMISSION - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Techniques for using at least one of omni-directional and directional antennas for communication are described. A station may be equipped antenna elements selectable for use as an omni-directional antenna or one or more directional antennas. The station may select the omni-directional antenna or a directional antenna for use for communication based on various factors such as, e.g., whether the location or direction of a target station for communication is known, whether control frames or data frames are being exchanged, etc. ## Claims ### Claim 1 A method of operating a wireless communications apparatus, comprising: sending a Request to Send (RTS) frame to a station via an omni-directional antenna; receiving a Clear to Send (CTS) frame from the station via the omni-directional antenna; determining an arrival direction of the received CTS frame; and selecting a directional antenna based on the arrival direction of the received CTS frame. ### Claim 2 (depends on 1) The method of claim 1, further comprising: sending at least one data frame to the station via the selected directional antenna. ### Claim 3 (depends on 1) The method of claim 1, further comprising: determining received signal strength of the CTS frame for each of a plurality of directional antennas; and wherein said step of selecting a directional antenna includes selecting said directional antenna from said plurality of directional antennas, said selected directional antenna having a highest received signal strength of the CTS frame. ### Claim 4 (depends on 1) The method of claim 1, wherein said step of selecting a directional antenna based on the arrival direction of the received CTS frame includes selecting a directional antenna closest to the arrival direction of the CTS frame. ### Claim 5 (depends on 1) The method of claim 1, wherein said at least one data frame is sent to the station via the selected directional antenna starting within a short interframe space (SIFS) time. ### Claim 6 (depends on 2) The method of claim 2, further comprising: switching back to the omni-directional antenna after sending the at least one data frame to the station. ### Claim 7 An apparatus for wireless communication, comprising: at least one integrated circuit configured to: send a Request to Send (RTS) frame to a station via an omni-directional antenna; receive a Clear to Send (CTS) frame from the station via the omni-directional antenna; determine an arrival direction of the received CTS frame; and select a directional antenna based on the arrival direction of the received CTS frame. ### Claim 8 (depends on 7) The apparatus of claim 7, wherein said at least one integrated circuit is further configured to: send at least one data frame to the station via the selected directional antenna. ### Claim 9 (depends on 7) The apparatus of claim 7, wherein the at least one integrated circuit is further configured to determine received signal strength of the CTS frame for each of a plurality of directional antennas; and wherein said selected directional antenna is selected from said plurality of directional antennas, said selected directional antenna having a highest received signal strength of the CTS frame. ### Claim 10 An apparatus for wireless communication, comprising: means for sending a Request to Send (RTS) frame to a station via an omni-directional antenna; means for receiving a Clear to Send (CTS) frame from the station via the omni-directional antenna; means for determining an arrival direction of the received CTS frame; and means for selecting a directional antenna based on the arrival direction of the received CTS frame. ### Claim 11 (depends on 10) The apparatus of claim 10, further comprising: means for sending at least one data frame to the station via the selected directional antenna. ### Claim 12 (depends on 10) The apparatus of claim 10, further comprising: means for determining received signal strength of the CTS frame for each of a plurality of directional antennas; and wherein said means for selecting a directional antenna select said directional antenna from said plurality of directional antennas, said selected directional antenna having a highest received signal strength of the CTS frame. ### Claim 13 (depends on 10) The apparatus of claim 10, wherein said means for selecting a directional antenna based on the arrival direction of the received CTS frame select a directional antenna closest to the arrival direction of the CTS frame. ### Claim 14 (depends on 11) The apparatus of claim 11, further comprising: means for switching back to the omni-directional antenna after sending the at least one data frame to the station. ### Claim 15 A non-transitory computer readable medium comprising computer readable instructions stored thereon, the computer readable instructions executable by at least one computer to: send a Request to Send (RTS) frame to a station via an omni-directional antenna; receive a Clear to Send (CTS) frame from the station via the omni-directional antenna; determine an arrival direction of the received CTS frame; and select a directional antenna based on the arrival direction of the received CTS frame. ### Claim 16 (depends on 15) The non-transitory computer readable medium of claim 15, further comprising computer readable instructions executable by said at least one computer to: send at least one data frame to the station via the selected directional antenna. ### Claim 17 A station for wireless communication, comprising: an omni-directional antenna; a plurality of directional antennas; and at least one integrated circuit configured to: send a Request to Send (RTS) frame to another station via the omni-directional antenna; receive a Clear to Send (CTS) frame from the other station via the omni-directional antenna; determine an arrival direction of the received CTS frame; select a directional antenna from among the plurality of directional antennas based on the arrival direction of the received CTS frame. ### Claim 18 (depends on 17) The station of claim 17, wherein said at least one integrated circuit is further configured to: send at least one data frame to the other station via the selected directional antenna. ### Claim 19 (depends on 17) The station of claim 17, wherein said at least one integrated circuit is further configured to: determine received signal strength of the CTS frame for each of a plurality of directional antennas; and select said directional antenna from said plurality of directional antennas, said selected directional antenna having a highest received signal strength of the CTS frame. ### Claim 20 (depends on 18) The station of claim 18, wherein said at least one integrated circuit is further configured to: control said station to switch back to the omni-directional antenna after sending the at least one data frame to the station.