Link adaptation a communication network
18 claims: 4 independent, 14 dependent
- 1ネットワークのリンク適合を行う方法であり、 制御フィールドを生成する段階 であって、リンク品質情報の要求を示すように前記制御フィールドに第1ビットを設定することを含む、段階 と、 第1ヘッダを有する第1通信フレームを生成する段階と、 前記第1通信フレームを送信する段階と、 第1通信デバイスと第2通信デバイスとの間の無線通信リンクに対応するリンク品質メトリックを決定する段階と、 第2ヘッダを有する第2通信フレームを生成する段階と、 前記第2通信フレームを送信する段階と を備え、 前記第1ヘッダは、前記 制御フィールド を含み、 前記第1通信フレームは、i)サウンディングフレームではなく、ii)ヌルデータパケットが前記第1通信フレームに続くことをアナウンスするフレームではなく、 前記制御フィールドを生成する段階は、さらに、前記制御フィールドを第1通信プロトコルに従ってインタープリトし、第2通信プロトコルに従ってインタープリトしないことを示す値 に 前記制御フィールドの第2 ビットを 設定する段階をさらに有し、 前記第2通信プロトコルは、i)サウンディングフレーム であり 、 または ii)ヌルデータパケットが通信フレームに続くことをアナウンスするフレーム である 前記通信フレーム においてのみ リンク品質情報の 前記 要求を 示すように前記制御フィールド内に前記第1ビットを設定することを 許可 し 、 前記第2ヘッダは、 i)前記無線通信リンクを介して用いる変調符号化方式を指定する前記制御フィールドの第3サブフィールドと ii)前記リンク品質メトリックを含む前記制御フィールドの第4サブフィールドと 含 み 、 前記第2通信プロトコルは、チャネル状態情報またはビーム形成フィードバックの要求を示すための前記第4サブフィールドに対応する複数のビットを指定する、 方法。
- 2前記リンク品質メトリックは、i)信号対雑音比(SNR)、ii)受信信号強度インジケータ(RSSI)、およびiii)リンクマージン メトリック のうちの少なくとも1つを含む請求項1に記載の方法。
- 3前記変調符号化方式を決定する段階と、 決定された前記変調符号化方式の指標を前記第3サブフィールドに含める段階と をさらに備える、請求項1または2に記載の方法。
- 4前記第3サブフィールドに変調符号化方式フィードバックが利用可能でないことを示す値を設定する段階をさらに備える、請求項1から3のいずれか1項に記載の方法。
- 5前記第2ヘッダ内の前記制御フィールドを前記第1通信プロトコルに従ってインタープリトし、前記第2通信プロトコルに従ってインタープリトしないことを示す値を、前記第2ヘッダ内の前記制御フィールドの 第5 サブフィールドに設定する段階をさらに備え、 前記第2通信プロトコルは、前記リンク品質メトリックを指定する前記制御フィールドの前記第 4 サブフィールドを含まない、請求項1から4のいずれか1項に記載の方法。
- 6ネットワークインタフェースを備え、 前記ネットワークインタフェースは、 制 御フィールドを生成し、 第1ヘッダを有する第1通信フレームを生成し、 前記第1通信フレームが送信されるようにし、 前記ネットワークインタフェースと他の通信デバイスとの間の無線通信リンクに対応するリンク品質メトリックを決定し、 第2ヘッダを有する第2通信フレームを生成し、 さらに、前記第2通信フレームが送信されるようにし、 前記制御フィールドを生成することは、リンク品質情報の要求を示す第1ビットを前記制御フィールドに設定することを含み、 前記第1ヘッダは、前記 制御フィールド を含み、 前記第1通信フレームは、i)サウンディングフレームではなく、ii)ヌルデータパケットが前記第1通信フレームに続くことをアナウンスするフレームではなく、 前記制御フィールドを生成することは、前記制御フィールドを第1通信プロトコルに従ってインタープリトし、第2通信プロトコルに従ってインタープリトしないことを示す値 に 前記制御フィールドの第2 ビットを 設定することを含み、 前記第2通信プロトコルは、i)サウンディングフレーム であり 、 または ii)ヌルデータパケットが通信フレームに続くことをアナウンスするフレーム である 前記通信フレームに おいてのみ リンク品質情報の 前記 要求を 示すように前記制御フィールドに前記第1ビットを設定することを 許可 し 、 前記第2ヘッダは、 i)前記無線通信リンクを介して用いる変調符号化方式を指定する前記制御フィールドの第3サブフィールドと ii)前記リンク品質メトリックを含む前記制御フィールドの第4サブフィールドと 含 み 、 前記第2通信プロトコルは、チャネル状態情報またはビーム形成フィードバックの要求を示すための前記第4サブフィールドに対応する複数のビットを指定する、 装置。
- 7前記リンク品質メトリックは、i)信号対雑音比(SNR)、ii)受信信号強度インジケータ(RSSI)、およびiii)リンクマージン メトリック のうちの少なくとも1つを含む、請求項6に記載の装置。
- 8前記ネットワークインタフェースはさらに 前記変調符号化方式を決定し、 決定された前記変調符号化方式の指標を前記第3サブフィールドに含める、請求項6または7に記載の装置。
- 9前記ネットワークインタフェースはさらに、前記第3サブフィールドに変調符号化方式フィードバックが利用可能でないことを示す値を設定する、請求項6から8のいずれか1項に記載の装置。
- 10前記ネットワークインタフェースはさらに、 前記第2ヘッダ内の前記制御フィールドを前記第1通信プロトコルに従ってインタープリトし、前記第2通信プロトコルに従ってインタープリトしないことを示す値 に 、前記第2ヘッダ内の前記制御フィールドの 第5 サブフィールドに設定し、 前記第2通信プロトコルは、前記リンク品質メトリックを指定する前記制御フィールドの前記第 4 サブフィールドを含まない、請求項6から9のいずれか1項に記載の装置。
- 11ネットワークのリンク適合を行う方法であり、 制 御フィールドを生成する段階と、 ヘッダを有する通信フレームを生成する段階と、 前記通信フレームを送信する段階と を備え、 前記制御フィールドを生成する段階は、リンク品質情報の要求を示すように前記制御フィールドに第1ビットを設定することを含み、 前記ヘッダは、前記 制御フィールド を含み、 前記通信フレームは、i)サウンディングフレームではなく、ii)ヌルデータパケットが前記通信フレームに続くことをアナウンスするフレームではなく、 前記制御フィールドを生成する段階は、前記制御フィールドを第1通信プロトコルに従ってインタープリトし、第2通信プロトコルに従ってインタープリトしないことを示す値 に 前記制御フィールドの第2 ビットを 設定する段階を有し、 前記第2通信プロトコルは、i)サウンディングフレーム であり 、 または ii)ヌルデータパケットが通信フレームに続くことをアナウンスするフレーム である 前記通信フレーム においてのみ リンク品質情報の 前記 要求を 示すように前記制御フィールドに前記第1ビットを設定することを 許可 する 、方法。
- 12前記制御フィールドを生成する段階は、さらに、前記通信フレームがシングルユーザフレームであるかマルチユーザフレームであるかを示すよう第 3 サブフィールドを設定する段階を有し、 前記通信フレームを生成する段階は、i)前記第 3 サブフィールドがシングルユーザフレームを示すよう設定されている場合、前記通信フレームをシングルユーザフレームとして生成し、ii)前記第 3 サブフィールドがマルチユーザフレームを示すよう設定されている場合、前記通信フレームをマルチユーザフレームとして生成する段階を有する、請求項11に記載の方法。
- 13前記ヘッダが、メディアアクセス制御プロトコルデータユニットのメディアアクセス制御ヘッダである、請求項11または12に記載の方法。
- 14ネットワークインタフェースを備え、 前記ネットワークインタフェースは、 制 御フィールドを生成し、 ヘッダを有する通信フレームを生成し、 前記通信フレームが送信されるようにし、 前記制御フィールドを生成することは、リンク品質情報の要求を示すように前記制御フィールドに第1ビットを設定することを含み、 前記ヘッダは、前記 制御フィールド を含み、 前記通信フレームは、i)サウンディングフレームではなく、ii)ヌルデータパケットが前記通信フレームに続くことをアナウンスするフレームではなく、 前記制御フィールドを生成することは、前記制御フィールドを第1通信プロトコルに従ってインタープリトし、第2通信プロトコルに従ってインタープリトしないことを示す値 に 前記制御フィールドの第2 ビットを 設定することを含み、 前記第2通信プロトコルは、i)サウンディングフレーム であり 、 または ii)ヌルデータパケットが通信フレームに続くことをアナウンスするフレーム である 前記通信フレーム においてのみ リンク品質情報の 前記 要求を 示すように前記制御フィールドに前記第1ビットを設定することを 許可 する 、装置。
- 15前記ネットワークインタフェースは、前記通信フレームがシングルユーザフレームであるかマルチユーザフレームであるかを示すよう第 3 サブフィールドを設定し、 前記ネットワークインタフェースは、i)前記第 3 サブフィールドがシングルユーザフレームを示すよう設定されている場合、前記通信フレームをシングルユーザフレームとして生成し、ii)前記第 3 サブフィールドがマルチユーザフレームを示すよう設定されている場合、前記通信フレームをマルチユーザフレームとして生成する、請求項14に記載の装置。
- 16前記ヘッダが、メディアアクセス制御プロトコルデータユニットのメディアアクセス制御ヘッダである、請求項14または15に記載の装置。
- 17前記ネットワークインタフェースはメディアアクセス制御処理ユニットを含み、 前記メディアアクセス制御処理ユニットは前記制御フィールドを生成し、 前記メディアアクセス制御処理ユニットは前記メディアアクセス制御ヘッダを生成し、 前記メディアアクセス制御処理ユニットは前記メディアアクセス制御プロトコルデータユニットを生成する、請求項16に記載の装置。
- 18前記ネットワークインタフェースは物理層処理ユニットを含み、 前記物理層処理ユニットは前記メディアアクセス制御プロトコルデータユニットを含む前記通信フレームを生成する、請求項16または17に記載の装置。
Independent claims18
93 paragraphs, as filed
The present invention generally relates to a communication network, and more particularly to a communication network in which information is exchanged between devices in order to adapt a communication link in response to a change in channel conditions, for example.
[Priority information] This disclosure claims the benefits of the following US provisional patent applications: The title of the invention filed on September 1, 2010 is "Link Adaptation in 802.11ac", US Provisional Patent Application No. 61 / 379,322, and the title of the invention filed on November 9, 2010 is "VHT Fast". US Provisional Patent Application No. 61 / 411,857 of "Link Adaptation", US Provisional Patent Application No. 61 / 416,154 of "VHT Fast Link Adaptation" with the title of the invention filed on November 22, 2010, January 6, 2011 The US provisional patent application No. 61 / 430,379 with the title of the invention filed on the date of "VHT Fast Link Adaptation" and the US provisional patent application with the title of the invention filed on March 10, 2011 "VHT Fast Link Adaptation" Patent application No. 61 / 451,431.
All of the disclosures of the patent applications referenced above are incorporated herein by reference in their entirety.
The description of the background techniques provided herein is intended to present the background of the present disclosure in general. The aspects of the invention by the inventors described in this background art section and the description not recognized as prior art at the time of filing are not recognized as prior art of the present disclosure, either express or implied.
A wireless local area network (WLAN) typically includes an access point (AP) and one or more client stations when operating in infrastructure mode. WLAN has grown rapidly over the last decade. The development of WLAN standards such as the Institute for Electrical and Electronics Engineers (IEEE) 802.11a, 802.11b, 802.11g, and 802.11n standards has improved peak data throughput for single users. For example, the IEEE802.11b standard has a single-user peak throughput of 11 megabits per second (Mbps), the IEEE802.11a and 802.11g standards have a single-user peak throughput of 54 Mbps, and the IEEE802.11n standard has a single-user peak throughput. The peak throughput is 600 Mbps. Research toward the new standard IEEE802.11ac has begun, and higher throughput is expected.
<p num="0006"> In one embodiment, the method of network link matching produces a communication frame with a header and a step of determining the link quality metric corresponding to the wireless communication link between the first communication device and the second communication device. Containing a step and a step of transmitting a communication frame, the header contains i) the first subfield of the control field that specifies the modulation coding scheme to use over the wireless communication link and ii) the control field that contains the link quality metric. Includes second subfield.</p><p num="0007"> In other embodiments, the device comprises a network interface, which determines the link quality metric corresponding to the wireless communication link between the network interface and another communication device and produces a communication frame with a header. The headers are i) the first subfield of the control field that specifies the modulation coding method used over the wireless communication link and ii) the second subfield of the control field that contains the link quality metric. Including with field.</p><p num="0008"> In yet another embodiment, the method of link matching the network includes a step of generating a control field to include a first subfield indicating a request for link quality information, a step of generating a communication frame with a header, and a communication. Including the stage of transmitting the frame, 1) the header contains the first subfield, 2) the communication frame is not i) the sounding frame, but ii) in the frame announcing that the null data packet follows the communication frame. Absent.</p><p num="0009"> In yet another embodiment, the device includes a network interface, which generates a control field to include a first subfield indicating a request for link quality information, a communication frame with a header, and a communication frame. The header contains the first subfield, and the communication frame is not i) a sounding frame and ii) a frame announcing that a null data packet follows the communication frame.</p>
<figref num="1">FIG. 1 is a block diagram of an exemplary wireless local area network (WLAN) 10 according to an embodiment.</figref><figref num="2A">FIG. 2A is a diagram showing a control frame format of the prior art.</figref><figref num="2B">FIG. 2B is a diagram showing a control frame format of the prior art.</figref><figref num="2C">FIG. 2C is a diagram showing a control frame format of the prior art.</figref><figref num="3A">FIG. 3A is a diagram showing an exemplary control frame format according to an embodiment.</figref><figref num="3B">FIG. 3B is a diagram showing an exemplary control frame format according to an embodiment.</figref><figref num="4A">FIG. 4A is a diagram showing other exemplary control frame formats according to other embodiments.</figref><figref num="4B">FIG. 4B is a diagram showing other exemplary control frame formats according to other embodiments.</figref><figref num="5">FIG. 5 is a diagram showing other exemplary control frame formats according to other embodiments.</figref><figref num="6">FIG. 6 is a diagram showing an exemplary communication frame including a control frame according to an embodiment.</figref><figref num="7">FIG. 7 is a flow chart of an exemplary method of requesting information for link conformance according to an embodiment.</figref><figref num="8">FIG. 8 is a flow chart of an exemplary method for generating and providing information for link matching according to an embodiment.</figref><figref num="9">FIG. 9 is a flow chart of an exemplary method of generating and providing non-required information in order to perform link conformance in one embodiment.</figref><figref num="10">FIG. 10 is a flow chart of an exemplary method of determining a beam formation vector using link quality information in one embodiment.</figref><figref num="11">FIG. 11 is a flow chart of an exemplary method of determining a calibration matrix using link quality information in one embodiment.</figref><figref num="12">FIG. 12 is a timing chart of an exemplary transmit sequence in a downlink multi-user multi-input multi-output (MIMO) where modulation coding scheme (MCS) and / or link quality feedback is required by the access point in one embodiment. Is.</figref><figref num="13">FIG. 13 is a timing chart of other exemplary transmission sequences in downlink multi-user MIMO in which MCS and / or link quality feedback is required by the access point in other embodiments.</figref>
In the embodiment described below, the first network device, which is a client device in a wireless local area network (WLAN), transmits link quality information to a second network device, such as a WLAN access point (AP). In some embodiments and / or scenarios, the link quality information is transmitted by the first network device in response to a request for link quality information from the second network device. In some embodiments and / or scenarios, the link quality information transmitted by the first network device is unrequired. That is, it is transmitted under the initiative of the first network device, and does not respond to the request from the second network device. In various embodiments, the link quality information is one or more forms such as a modulation coding scheme indicator, signal-to-noise ratio (SNR) information, received signal strength indicator (RSSI), link margin, and the like.
FIG. 1 is a block diagram of an exemplary wireless local area network (WLAN) 10 according to an embodiment. AP14 includes a host processor 15 coupled to network interface 16. The network interface 16 includes a medium access control (MAC) processing unit 18 and a physical layer (PHY) processing unit 20. The PHY processing unit 20 includes a plurality of transceivers 21, and the transceiver 21 is coupled to the plurality of antennas 24. Although FIG. 1 illustrates three transceivers 21 and three antennas 24, in other embodiments the AP 14 includes a different number of transceivers 21 and antennas 24 (eg, 1, 2, 4, 5, etc.). In one embodiment, the MAC processing unit 18 and the PHY processing unit 20 operate according to the first communication protocol (for example, the currently standardized IEEE 802.11ac standard). In other embodiments, the MAC processing unit 18 and the PHY processing unit 20 operate according to a second communication protocol (eg, such as the IEEE 802.11n standard).
WLAN10 includes a plurality of client stations 25. Although four client stations 25 are illustrated in FIG. 1, in various scenarios and embodiments, WLAN 10 includes a different number of client stations 25 (eg, 1, 2, 3, 5, 6, etc.). At least one of client stations 25 (for example, client station 25-1) operates according to at least the first communication protocol. In some embodiments, at least one of the client stations 25 does not operate according to the first communication protocol, but operates according to the second communication protocol (hereinafter sometimes referred to as "legacy client station").
Client station 25-1 includes a host processor 26 coupled to network interface 27. The network interface 27 includes a MAC processing unit 28 and a PHY processing unit 29. The PHY processing unit 29 includes a plurality of transceivers 30, and the transceiver 30 is coupled to a plurality of antennas 34. Although FIG. 1 illustrates three transceivers 30 and three antennas 34, in other embodiments the client station 25-1 has a different number of transceivers 30 and antennas (eg 1, 2, 4, 5, etc.). Including 34.
In one embodiment, one or both of client stations 25-2, 25-3 has the same or similar structure as client station 25-1. In one embodiment, client station 25-4 has a structure similar to client station 25-1, but does not operate according to the first communication protocol. Rather, in one embodiment, client stations 25-4 operate according to a second communication protocol. In various embodiments, the client station 25 having the same or similar structure as the client station 25-1 has the same or different number of transceivers or antennas. For example, in one embodiment, client station 25-2 has only two transceivers and two antennas.
In one embodiment, client stations 25-4 are legacy client stations. That is, the client station 25-4 cannot receive the communication frame transmitted by the AP14 or another client station 25 according to the first communication protocol, and cannot completely decode it. Similarly, in one embodiment, legacy client stations 25-4 cannot transmit communication frames according to the first communication protocol. On the other hand, the legacy client station 25-4 can receive the communication frame, completely decode it, and transmit it according to the second communication protocol.
In various embodiments, the MAC processing unit 18 and the PHY processing unit 20 of the AP 14 generate communication frames according to the first communication protocol. The transceiver 21 transmits the generated communication frame via the antenna 24. Similarly, the transceiver 21 receives a communication frame via the antenna 24. In various embodiments, the MAC processing unit 18 and the PHY processing unit 20 of the AP 14 process the received communication frame according to the first communication protocol.
In various embodiments, the MAC processing unit 28 and the PHY processing unit 29 of the client device 25-1 generate a communication frame according to the first communication protocol. The transceiver 30 transmits the generated communication frame via the antenna 34. Similarly, the transceiver 30 receives the communication frame via the antenna 34. In various embodiments, the MAC processing unit 28 and the PHY processing unit 29 of the client device 25-1 process the received communication frame according to the first communication protocol.
In Figure 2A, AP14 and / or client stations 25-1, 25-2, 25-3 transmit to legacy client station 25-4, and legacy client station 25-4 sends to AP14 and / or for the purpose of link matching. Alternatively, it is a diagram showing a control field 60 of the prior art to transmit to client stations 25-1, 25-2, 25-3. Control field 60 is defined in the IEEE 802.11n standard. The control field 60 is included in the MAC header of the communication frame. The control field 60 includes a link conformance control subfield 64 used to request a demodulation coding scheme (MCS) and transmit the MCS. The calibration position subfield 66 is used to indicate the position in the calibration sounding exchange sequence, and the calibration sequence subfield 68 is used to indicate an instance of the calibration procedure. Subfield 70 is reserved. The Channel State Information (CSI) / Steering Subfield 72 is used to indicate a request for CSI or beam formation feedback. The null data packet (NDP) announcement subfield 74 is used to announce that the NDP sounding packet follows a frame containing control field 60. A sounding packet is a communication frame having a training field that allows the determination of channel estimates for a multi-input, multi-output (MIMO) communication channel, i.e., a training field that sounds the dimensions of the available MIMO channels.
Control frame 60 also includes reserved subfield 76. Control frame 60 has access category (AC) constraint subfield 78 and reverse permission (RDG) / additional PPDU subfield 80 for transmit opportunity (TXOP) holders that allow other stations to transmit data during TXOP. Also includes.
FIG. 2B is a diagram showing the link conformance control subfield 64 of FIG. 2A. The link fit control subfield 64 includes a reserved subfield 84 and a training request (TRQ) subfield 86. TRQ subfield 86 indicates whether the respondent to control field 60 is requested to send a sounding frame. The MCS Request or Antenna Selection (ASEL) Indicator (MAI) subfield 88 indicates whether the control subfield 64 should be interpreted as related to MCS feedback or as related to ASEL. .. When the MAI subfield 88 is set to a value of 14, this indicates that the control subfield 64 is interpreted as related to ASEL. When the MAI subfield 88 is set to a value other than 14, this indicates that the control subfield 64 is interpreted as illustrated in FIG. 2C. Referring to FIG. 2C, when the MAI subfield 88 is set to a value other than 14, the MAI subfield 88 is assumed to include the MCS request (MRQ) subfield 90 and the MRQ sequence identifier (MSI) subfield 92. It will be interpreted. When the MRQ subfield 90 is set to 1, the responder is requested to send MCS feedback (MFB) in response to receiving control field 60. If the MRQ subfield 90 is set to 0, no MFB is requested. When the MRQ subfield 90 is set to 1, the MSI subfield 92 is populated with a sequence number in the range 0-6 that specifies a particular MRQ. If the MRQ subfield 90 is set to 0, the MSI subfield 92 is reserved.
With reference to FIG. 2B again, the link conformance control subfield 64 includes an MCS feedback sequence identifier (MFSI) subfield 94 indicating the MSI corresponding to the MFB of the link conformance subfield 64. For example, the requester uses the control frame 60 (FIGS. 2A-2C) to set the MSI value of the MSI subfield 92 and sends the MCS request to the responder. The responder to the request sends MCS feedback (MFB) using the control frame 60 and sets the MSI value set by the requester in the MFSI subfield 94.
Link conformance control subfield 64 also includes MCS feedback and antenna selection command / data (MFB / ASELC) subfield 96. When the MAI subfield 88 is set to a value of 14, the MFB / ASELC subfield 96 is interpreted as containing ASEL data. On the other hand, when the MAI subfield 88 is set to a value other than 14, the MFB / ASELC subfield 96 is interpreted as indicating the recommended MCS. A value of 127 indicates that MCS feedback (MFB) is not provided.
According to the IEEE802.11n standard, network devices send frames with MRQ subfield 90 set to 1 only when i) the frame is a Sounding PHY Protocol Data Unit (PPDU), or ii. ) Announces that NDP will follow (that is, the NDP announcement subfield 74 is set to 1) and only in frames followed by NDP sounding packets.
In one embodiment, AP14 and / or client stations 25-1, 25-2, 25-3 use control field 60 to link match with legacy client station 25-4 and legacy client station 25-4. Uses control field 60 when link matching with AP14 and / or client stations 25-1, 25-2, 25-3.
In Figure 3A, AP14 transmits to one of client stations 25-1, 25-2, 25-3 and client stations 25-1, 25-2 for the purpose of link conformance according to one embodiment. , 25-3 is a diagram showing an exemplary control field 120 that one of 25-3 sends to AP14. The control field 120 is a subfield indicating whether the control field 120 should be interpreted according to the format shown in FIG. 3A or the format shown in FIG. 2A.<u style="single">121</u>including. For example, subfield<u style="single">121</u>If a first value (for example, 0) is set for, the control field will be interpreted according to the format shown in Figure 2A. Meanwhile, subfields<u style="single">121</u>If a second value (for example, 1) is set for, the control field will be interpreted according to the format shown in Figure 3A.
Subfield 122 is used to indicate whether control field 120 contains unsolicited, i.e., link conformance feedback that is not sent in response to the MRQ. When the MRQ subfield 124 is set to 1, the responder is requested to send MCS feedback (MFB) in response to receiving control field 120. If the MRQ subfield 120 is set to 0, no MFB is requested. When the MRQ subfield 124 is set to 1, the MSI subfield 126 is populated with a sequence number in the range 0-6 that specifies a particular MRQ. If the MRQ subfield 124 is set to 0, the MSI subfield 126 is reserved.
The MCS Feedback Sequence Identifier (MFSI) / GID-L subfield 128 indicates the MSI corresponding to the MFB in control field 120. For example, the requester uses the control frame 120 to set the MSI value of the MSI subfield 126 and sends the MCS request to the responder. The responder to the request sends MCS feedback (MFB) using the control frame 120 and sets the MSI value set by the requester in the MFSI / GID-L field 128. In one embodiment, if the subfield 122 is set to indicate that the control field 120 contains unsolicited link conformance feedback, the MFSI / GID-L field is referenced to be calculated based on the unsolicited MFB. Represents the lower 3 bits of the frame's group ID.
The MFB subfield 130 is used to transmit MFB information and / or other information related to link quality. FIG. 3B is a diagram showing the MFB subfield 130 according to the embodiment. The MFB subfield 130 includes a subfield 132 indicating the number of spatiotemporal streams to which MFB information and / or other information about link quality corresponds. The MCS subfield 134 is used to provide an indicator of the proposed modulation coding scheme (MCS) used to transmit over the link. In one embodiment, a given value (such as 15, or any other suitable value) indicates that MCS feedback is not available. Subfield 136 is used to provide information about link quality other than the proposed MCS and the number of proposed spatiotemporal streams. In one embodiment, subfield 136 is used to provide signal-to-noise ratio (SNR) information about the link. In one embodiment, SNR information is measured by the responder over multiple Orthogonal Frequency Division Multiplexing (OFDM) tones or subchannels (eg, all tones, all data tones, etc.) and between all spatial streams. Includes values that indicate the averaged, average SNR (eg, expressed in decibels). In one embodiment, the SNR information<maths num="1"><img id="000002" he="18" wi="134" file="JP6029110B2_D0001.tif" img-format="tif" img-content="drawing" /></maths>(Formula 1) and<maths num="2"><img id="000003" he="9" wi="134" file="JP6029110B2_D0001.tif" img-format="tif" img-content="drawing" /></maths>It is determined according to (Formula 2). Here N<sub>STS</sub>Is the number of spatial streams,<maths num="3"><img id="000004" he="10" wi="133" file="JP6029110B2_D0001.tif" img-format="tif" img-content="drawing" /></maths>Is the number of data tones, k is the tone index, and N<sub>SR</sub>Is the maximum tone index value, N<sub>SR</sub>Is the minimum tone index value, i<sub>STS</sub>Is a spatial stream index,<maths num="4"><img id="000005" he="8" wi="134" file="JP6029110B2_D0001.tif" img-format="tif" img-content="drawing" /></maths>Is i<sub>STS</sub>The SNR value of the kth tone of the th spatial stream. In Equation 2, the value in square brackets is a value quantized into an 8-bit (or other suitable number of bits) two's complement (or other suitable format).
In other embodiments, the SNR information includes a single SNR value, which is the smallest of all spatial streams, the SNR value averaged over multiple tones. In other embodiments, the SNR information is i) an average SNR averaged across all spatial streams across multiple OFDM tones measured by the responder (eg, all tones, or all data tones). Includes a single SNR value that is the smallest of all spatial streams, the SNR value averaged over multiple tones. In other embodiments, the SNR information includes a link margin value that is the difference between the measured SNR and the MCS sensitivity point indicated by the MCS subfield 134.
In another embodiment, subfield 136 includes a received signal strength indicator (RSSI).
In one embodiment, the GID-H subfield 138 is valid when the subfield 122 is set to indicate that the control field 120 contains unsolicited link conformance feedback, and the GID-H subfield 138 is Represents the upper 3 bits of the group ID in the referenced frame calculated based on the unrequested MFB. The coded type subfield 140 is valid when the subfield 122 is set to indicate that the control field 120 contains unsolicited link conformance feedback, and the coded type subfield 140 is based on the unsolicited MFB. Represents the error-controlled coding type (BCC or LDPC) in the referenced frame calculated in. The feedback Tx type subfield 142 is valid when the subfield 122 is set to indicate that the control field 120 contains unsolicited link conformance feedback, and the feedback Tx type subfield 142 indicates that the transmit beam formation is Indicates whether the unsolicited MFB is applied in the referenced frame calculated based on it.
Control field 120 includes reserved subfield 144. Control frame 120 also includes access category (AC) constraint subfield 146 for transmit opportunity (TXOP) holders that allow data transmission to other stations during TXOP, and reverse allow (RDG) / additional PPDU subfield 148. Including.
In other embodiments, the appropriate bit order and number of subfields different from the examples shown in FIGS. 3A and 3B are used. For example, FIGS. 4A, 4B, 5 show other examples of bit order and number.
In FIG. 4A, AP14 transmits to one of client stations 25-1, 25-2, 25-3, or client stations 25-1, 25-, for the purpose of link conformance according to one embodiment. It is a figure which shows the other exemplary control field 200 that any one of 2, 25-3 sends to AP14. Similar to the exemplary control field 120 in FIG. 3A, the control field 200 should be interpreted according to the format shown in FIG. 4A or the format shown in FIG. 2A. Subfield indicating<u style="single">121</u>including. For example, subfield<u style="single">121</u>If a first value (for example, 0) is set for, the control field will be interpreted according to the format shown in Figure 2A. Meanwhile, subfields<u style="single">121</u>If a second value (for example, 1) is set for, the control field will be interpreted according to the format shown in Figure 4A.
The control field 200 is similar to the control field 120 of FIG. 3A, and the description of the similarly numbered elements is not repeated. Compared to control field 120 in FIG. 3A, reserved subfield 204 and unsolicited FB subfield 208 are in different locations within the control field. In addition, the MFB subfield 212 has a different format than the MFB subfield 130 of FIG. 3B.
Subfield 216 is similar to subfield 136 in FIG. 3B, but with two fewer bits. Subfield 212 also includes bandwidth (BW) subfield 220. Bandwidth (BW) subfield 220 indicates the bandwidth of the received communication frame used for MCS selection and / or link quality determination and corresponding to the values in fields 134 and / or 216. BW subfield 220 is unrequired if the receiver of control field 200 is not aware of the bandwidth of the communication frame corresponding to the values in fields 134 and / or 216 used for MCS selection and / or link quality determination. Used for feedback (that is, when the unsolicited feedback subfield 208 is set to indicate unsolicited feedback). In one embodiment, the BW subfield 220 is reserved if the unsolicited feedback subfield 208 is not configured to indicate unsolicited feedback.
FIG. 5 shows that AP14 transmits to any one of client stations 25-1, 25-2, 25-3, or client stations 25-1, 25-, for the purpose of link conformance according to one embodiment. It is a figure which shows the other exemplary control field 250 which any one of 2, 25-3 transmits to AP14. Similar to the exemplary control field 120 in FIG. 3A and the exemplary control field 200 in FIG. 4A, control field 200 should be interpreted in FIG. 2A to see if the control field 200 should be interpreted according to the format shown in FIG. A subfield that indicates whether it should be interpreted according to the format shown<u style="single">121</u>including. For example, subfield<u style="single">121</u>If a first value (for example, 0) is set for, the control field will be interpreted according to the format shown in Figure 2A. Meanwhile, subfields<u style="single">121</u>If a second value (for example, 1) is set for, the control field will be interpreted according to the format shown in Figure 5.
The control field 250 is similar to the control field 200 of FIG. 4A (and the control field 120 of FIG. 3A), and the description of the similarly numbered elements is not repeated. Like the control field 200 in FIG. 4A, the reserved subfield 204 and the unsolicited FB subfield 208 are in different locations within the control field compared to the control field 120 in FIG. 3A. In one embodiment, the MFB subfield 130 has the same format as the MFB subfield 130 of FIG. 3B.
If the unsolicited FB subfield 208 is set to a value that does not indicate unsolicited feedback, and if the MRQ subfield 124 is set to 1, then the MSI multi-user (MU) indicator subfield 254 is set to 0 as an example. Sets the sequence number that identifies a particular MRQ, selected from the range ~ 6. In one embodiment, if the unsolicited FB subfield 208 is set to a value indicating unsolicited feedback, to indicate whether the feedback in subfield 130 is associated with single-user or multi-user transmissions. , Interpret the bits in subfield 254 again. In other embodiments, if the unsolicited FB subfield 208 is set to a value indicating unsolicited feedback, it is set to indicate whether the feedback is associated with single-user or multi-user transmissions. Interpret the MRQ subfield 124 again to include the bits.
In one embodiment, the unsolicited FB subfield 208 is set to a value indicating unsolicited feedback, and subfield 254 indicates that the feedback in subfield 130 is associated with single-user transmission, MCS selection and /. Or used in link quality determination, the 2 bits of subfield 258 are reinterpreted and the 3rd bit of subfield 258 is reserved to indicate the bandwidth of the communication frame corresponding to the value of subfield 130. It will be interpreted again. If the unsolicited FB subfield 208 is set to a value indicating unsolicited feedback, but subfield 254 indicates that the feedback in subfield 130 is associated with multi-user transmission, then the recipient of control field 250 Is used for MCS selection and / or link quality determination, and the bandwidth of the communication frame corresponding to the value in subfield 130 is based on the group identifier in subfield 258, which indicates the group of stations to which the communication frame was transmitted. Can be decided. In another embodiment, the unsolicited FB subfield 208 is set to a value indicating unsolicited feedback, but subfield 254 indicates that the feedback in subfield 130 is associated with multi-user transmission. Used for MCS selection and / or link quality determination, the 2 bits of subfield 258 are reinterpreted to indicate the bandwidth of the communication frame corresponding to the value in subfield 130, and the 3rd bit of subfield 258 is , Will be interpreted again as reserved. In other embodiments, if the unsolicited FB subfield 208 is set to a value indicating unsolicited feedback and the subfield 124 indicates that the feedback in the subfield 130 is associated with a single user transmission, then MCS selection and / Or used in link quality determination, subfield to indicate the bandwidth of the communication frame corresponding to the value in subfield 130
FIG. 6 is a diagram illustrating an exemplary communication frame 280 used to transmit a control frame as described with reference to FIGS. 3A, 3B, 4A, 4B, 5 in some embodiments. Frame 280 contains the MAC Protocol Data Unit (MPDU) 284 and the PHY Header 286. The MPDU 284 includes a MAC header 288, a MAC Service Data Unit (MSDU) 290, and a Cyclic Redundancy Check (CRC) field 292. In other embodiments where the control field 294 is included in the MAC header 288, the control field 294 is included in the PHY header 286. In one embodiment, the control frame 294 has a format as shown in FIG. 3A. In another embodiment, the control frame 294 has a format as shown in FIG. 3B. In another embodiment, the control frame 294 has a format as shown in FIG. In other embodiments, the control frame 294 has other suitable formats. The PHY header 286 and the MAC header 288 are included in the header portion 296 of the communication frame. Therefore, the control field 294 is included in the header portion 296.
FIG. 7 is a flow diagram illustrating an exemplary method 300 of requesting information to perform link conformance in one embodiment. In one embodiment, method 300 is implemented by network interface 16 (eg, such as MAC processing unit 18 and / or PHY processing unit 20). In another embodiment, method 300 is implemented by network interface 27 (eg, such as MAC processing unit 28 and / or PHY processing unit 29). In other embodiments, method 300 is implemented by other suitable network interfaces.
At block 304, a control field to be included in the communication frame is generated. In one embodiment, the control field is a field in the MAC header and is included in the MAC header of the communication frame. In one embodiment, the control frame has a format as shown in FIG. 3A. In another embodiment, the control frame has a format as shown in FIG. 4A. In another embodiment, the control frame has a format as shown in FIG. In other embodiments, the control frame has other suitable formats.
In one embodiment, block 304 includes block 308 in which subfields of control fields are configured to indicate a request for link quality information. In one embodiment, the subfield indicates one or more requirements of MCS, SNR information, RSSI, link margin information, and the like. In some embodiments, block 308 comprises setting a value in the MRQ subfield 124 (FIGS. 3A, 4A or 5) to indicate a request. In some embodiments, block 304 identifies a particular request in MSI subfield 126 (FIG. 3A or 4A), or MSI / MU subfield 254 (FIG. 5) (eg, in the range 0-6 or elsewhere). Includes setting sequence numbers (such as the appropriate range).
In one embodiment, block 304 includes block 312 that sets a value in the subfield to indicate that the control feel is interpreted according to the first communication protocol and not according to the second communication protocol. In some embodiments, block 312 subfields a value indicating that the control field is interpreted according to the first communication protocol and not according to the second communication protocol.<u style="single">121</u>Including setting to.
In one embodiment, block 304 includes both block 308 and block 312. In one embodiment, block 304 includes block 308, while block 304 and method 300 omit block 312.
In block 316, a communication frame containing the control field generated in block 304 is generated. In one embodiment, block 316 comprises generating a MAC header for a communication frame containing the control fields generated in block 304.
In block 320, the communication frame generated in block 316 is transmitted to or initiated from another device in the communication system.
In one embodiment and some scenarios, communication frames generated in block 316 and transmitted in block 320 are not sounding packets, but null in subsequent frames (such as null data packet (NDP) announcement frames). Yes, in a communication frame that contains an indicator that a data packet is being sent. In other embodiments and / or scenarios, the communication frame generated in block 316 and transmitted in block 320 is a sounding packet or an NDP announcement frame.
FIG. 8 is a flow diagram illustrating an exemplary method 400 that, in one embodiment, generates and provides information for link matching. In one embodiment, method 400 is implemented by network interface 16 (eg, such as MAC processing unit 18 and / or PHY processing unit 20). In another embodiment, method 400 is implemented by network interface 27 (eg, such as MAC processing unit 28 and / or PHY processing unit 29). In other embodiments, method 400 is implemented by other suitable network interfaces.
At block 404, the first communication frame with the first control field is received. In one embodiment, the first control field is included in the field of the MAC header of the first communication frame. The first control field includes a subfield containing an indicator indicating a request for link quality information. In one embodiment, the first control frame has a format as shown in FIG. 3A. In another embodiment, the first control frame has a format as shown in FIG. 4A. In another embodiment, the first control frame has a format as shown in FIG. In other embodiments, the first control frame has other suitable formats. In some embodiments, the subfield is an MRQ subfield 124 (FIGS. 3A, 4A or 5) configured to indicate a request for link quality information. In some embodiments, MSI subfield 126 (FIG. 3A or 4A) or MSI / MU subfield 254 (FIG. 5) identifies a particular MRQ request (eg, in the range 0-6, or other suitable. Set the sequence number (of the range).
In block 408, the proposed MCS is determined based on the first communication frame received in block 404. Appropriate techniques will be used to determine the proposed MCS, such as those known to those of skill in the art.
At block 412, the link quality metric is determined based on the first communication frame received at block 404. Appropriate techniques are used to determine the link quality metric, such as those known to those of skill in the art. In one embodiment, the link quality metric is a signal-to-noise ratio (SNR) metric for the first communication frame received at block 404. In one embodiment, the SNR metric spans multiple OFDM tones (eg, all tones, all data tones, etc.) measured by a network interface performing method 400 with respect to the first communication frame received in block 404. Corresponds to a value indicating the average SNR (eg, expressed in decibels) averaged across all spatial streams. In one embodiment, the SNR metric is determined according to Equation 1. In another embodiment, the metric is a single SNR value, which is the smallest, averaged SNR value across multiple tones of all spatial streams for the first communication frame received in block 404. In other embodiments, the SNR metric is i) averaging across all OFDM tones (eg, all tones, or all data tones) for the first communication frame received in block 404 across all spatial streams. A value indicating the averaged SNR, and ii) a single SNR value, which is the smallest SNR value averaged over multiple tones of all spatial streams for the first communication frame received in block 404. Including. In another embodiment, the link quality metric includes a link margin value that is the difference between the measured SNR and the MCS sensitivity point indicated by the MCS subfield 134 for the first communication frame received in block 404. In another embodiment, the link quality indicator includes a received signal strength indicator (RSSI) for the first communication frame received in block 404.
In block 416, the second control field to be included in the second communication frame is generated to include the MCS index determined in block 408 and the link quality metric index determined in block 412. In one embodiment, the second control field is a field in the MAC header and is included in the MAC header of the second communication frame. In one embodiment, the second control frame has a format as shown in FIG. 3A. In another embodiment, the second control frame has a format as shown in FIG. 3B. In another embodiment, the second control frame has a format as shown in FIG. In other embodiments, the second control frame has other suitable formats. In one embodiment, the MCS index is included in subfield 134. In one embodiment, indicators of the link quality metric are included in subfield 136 (FIG. 3A). In other embodiments, indicators of link quality metrics are included in subfield 216 (FIG. 4A). In one embodiment, the index of the link quality metric is determined according to Equation 2.
In one embodiment, block 416 comprises setting the MFSI subfield 128 (FIGS. 3A, 4A or 5) to the sequence number contained in the MSI or MSI / MU subfield of the first control field (block 404). In one embodiment, the block 416 has subfield 122 (FIG. 3A) or subfield 208 (FIG. 4A or 5) containing the link quality information contained in the second control field (eg, the first control of the first communication frame). Includes setting a value to indicate that it is in response to a request for link quality information (such as in response to a field) (block 404).
In one embodiment, block 416 comprises setting a subfield of the second control field with a value indicating that the second control field is interpreted according to the first communication protocol and not according to the second communication protocol. Including 420. In some embodiments, block 420 is a subfield to indicate that the second control field is interpreted according to the first communication protocol and not according to the second communication protocol.<u style="single">121</u>Including setting. In one embodiment, block 416 and method 400 omit block 420.
At block 424, the second communication frame is generated to include the second control field generated at block 416. In one embodiment, block 424 comprises generating a MAC header for a second communication frame containing a second control field generated in block 416.
In block 428, the second communication frame generated in block 424 is transmitted to or initiates transmission to the device that generated the first communication frame (block 404).
In one embodiment and some scenarios, the communication frame received in block 404 is not a sounding packet and is not a communication frame that includes an indicator that a null data packet is transmitted in a subsequent frame. In other embodiments and / or scenarios, the communication frame received in block 404 is a sounding packet.
In some embodiments, block 408 is omitted. In some embodiments where block 408 is omitted, block 416 comprises setting a subfield of the second control field to a value indicating that MCS feedback is not available. In one embodiment, the subfield 134 is set to a value indicating that MCS feedback is not available. In some embodiments where block 408 is omitted, block 416 omits setting the subfield of the second control field to indicate the proposed MCS.
FIG. 9 is a flow diagram illustrating an exemplary method 450 that, in one embodiment, generates and provides unsolicited information for link conformance. In one embodiment, method 450 is implemented by network interface 16 (eg, such as MAC processing unit 18 and / or PHY processing unit 20). In another embodiment, method 450 is implemented by network interface 27 (eg, such as MAC processing unit 28 and / or PHY processing unit 29). In other embodiments, method 450 is implemented by other suitable network interfaces.
At block 454, it is determined to send the unsolicited link quality information to another communication device. The determination of whether to transmit unsolicited link quality information to other communication devices is made in an appropriate manner, including using techniques known to those of skill in the art. For example, in one embodiment, the decision to send unsolicited link quality information to other communication devices is based on detecting changes in link quality (eg, increasing or decreasing SNR, RSSI, PER, etc.).
At block 458, the proposed MCS is determined based on the most recently received communication frame from another communication device. Appropriate techniques will be used to determine the proposed MCS, such as those known to those of skill in the art.
At block 462, the link quality metric is determined based on the most recently received communication frame from another communication device. In one embodiment, the most recently received communication frame used in block 462 is the same as the communication frame used in block 458. In another embodiment, the most recently received communication frame used in block 462 is different from the communication frame used in block 458.
Appropriate techniques are used to determine the link quality metric, such as those known to those of skill in the art. In one embodiment, the link quality metric is a signal-to-noise ratio (SNR) metric for the most recently received communication frame. In one embodiment, the SNR metric is multiple for the most recently received communication frame (eg, all tones, all data tones, etc.) as measured by the network interface performing method 450 for the most recently received communication frame. Corresponds to a value that indicates the average SNR (eg, expressed in decibels) averaged across all spatial streams over the OFDM tone of. In one embodiment, the SNR metric is determined according to Equation 1. In another embodiment, the metric is a single SNR value that is the smallest, averaged SNR value across multiple tones of all spatial streams for the most recently received communication frame. In other embodiments, the SNR metric is i) averaged across all spatial streams across multiple OFDM tones (eg, all tones, or all data tones) for the most recently received communication frame. It contains a value indicating the average SNR, and ii) a single SNR value that is the smallest SNR value averaged over multiple tones of all spatial streams for the most recently received communication frame. In another embodiment, the link quality metric includes a link margin value that is the difference between the measured SNR and the MCS sensitivity point indicated by the MCS subfield 134 for the most recently received communication frame. In other embodiments, the link quality indicator includes a received signal strength indicator (RSSI) for the most recently received communication frame.
At block 466, the control fields to be included in the communication frame are generated to include the MCS index determined in block 458 and the link quality metric index determined in block 462. In one embodiment, the control field is a field in the MAC header and is included in the MAC header of the communication frame. In one embodiment, the control frame has a format as shown in FIG. 3A. In another embodiment, the control frame has a format as shown in FIG. 3B. In another embodiment, the control frame has a format as shown in FIG. In other embodiments, the control frame has other suitable formats. In one embodiment, the MCS index is included in subfield 134. In one embodiment, indicators of the link quality metric are included in subfield 136 (FIG. 3A). In other embodiments, indicators of link quality metrics are included in subfield 216 (FIG. 4A). In one embodiment, the index of the link quality metric is determined according to Equation 2.
In one embodiment, block 466 sets subfield 122 (FIG. 3A) or subfield 208 (FIG. 4A or 5) to a value indicating that the link quality information contained in the control field is unrequired. Including. In one embodiment, if the MCS determined in block 458 and / or the link quality metric determined in block 462 is based on the received single user frame, block 466 is in the control field (eg, subfield 220 in FIG. 4B). Or include setting subfields (such as subfield 258 in Figure 5) to indicate the bandwidth of the received single-user frame based on the MCS determined in block 458 and / or the link quality metric determined in block 462. .. In one embodiment, if the MCS determined in block 458 and / or the link quality metric determined in block 462 is based on the received multi-user frame, block 466 is in the control field (eg, subfields 128, 138). Includes setting subfields (such as, 258) to indicate the group ID of the received multi-user frame based on the MCS determined in block 458 and / or the link quality metric determined in block 462.
In one embodiment, block 466 includes block 470, which sets a subfield of the control field with a value indicating that the control field is interpreted according to the first communication protocol and not according to the second communication protocol. In some embodiments, block 470 is a subfield to indicate that the control field is interpreted according to the first communication protocol and not according to the second communication protocol.<u style="single">121</u>Including setting. In one embodiment, block 466 and method 450 omit block 470.
At block 474, the communication frame is generated to include the control fields generated at block 466. In one embodiment, block 474 comprises generating a MAC header for a communication frame containing a control field generated in block 466.
In block 478, the communication frame generated in block 474 is transmitted to or initiated from the device that generated the communication frame used to generate the MCS and / or link quality information.
In some embodiments, block 462 is omitted. In some embodiments where block 462 is omitted, block 466 omits setting subfields within the control field to indicate a link quality metric.
Referring to FIGS. 8 and 9, in some embodiments and / or scenarios, the network interface of the communication device that receives the communication frame transmitted in block 428 or block 479 is in the control field (if included). Use the indicated MCS. In some embodiments and / or scenarios, the network interface of the communication device that receives the communication frame transmitted in block 428 or block 479 uses the link quality metric shown in the control field (if included). Determine the MCS used when transmitting to a communication device that implements Method 400/450.
FIG. 10 is a flow diagram illustrating an exemplary method 500 for determining a beam formation vector using link quality information in one embodiment. In one embodiment, method 500 is implemented by network interface 16 (eg, such as MAC processing unit 18 and / or PHY processing unit 20). In another embodiment, method 500 is implemented by network interface 27 (eg, such as MAC processing unit 28 and / or PHY processing unit 29). In other embodiments, method 500 is implemented by other suitable network interfaces.
At block 504, a plurality of communication frames, each requesting link quality information, are generated and transmitted to other communication devices. In one embodiment, each of the communication frames is transmitted using different beam forming vectors. In one embodiment, each of the communication frames is generated using the method described with reference to FIG. In one embodiment, the plurality of communication frames transmitted in block 504 are transmitted using the same MCS.
In block 508, a plurality of communication frames, each containing link quality information, are received from other communication devices in response to the transmission of the plurality of communication frames in block 504. In one embodiment, each of the other communication frames received in block 508 is generated by another communication device, such as by the method described with reference to FIG.
At block 512, the beam formation vector used for subsequent transmissions to other communication devices is determined based on the link quality information received at block 508. For example, in one embodiment, the beam forming vector that gives the highest SNR value is selected. As another example, in one embodiment, the beam forming vector that gives the highest link margin is selected. As another example, in one embodiment, the beam forming vector with the highest RSSI is selected. As another example, in one embodiment, a beam forming vector is generated using a set of beam forming vectors that gives the highest SNR value, link margin, RSSI, and the like. The beam formation vector determined in block 512 is used to transmit subsequent communication frames to other communication devices.
FIG. 11 is a flow diagram illustrating an exemplary method 600 of determining the calibration matrix used for implicit beam formation using link quality information in one embodiment. In one embodiment, method 600 is implemented by network interface 16 (eg, such as MAC processing unit 18 and / or PHY processing unit 20). In another embodiment, method 600 is implemented by network interface 27 (eg, such as MAC processing unit 28 and / or PHY processing unit 29). In other embodiments, method 600 is implemented by other suitable network interfaces.
At block 604, the communication frame from the second communication device is received by the first communication device. The communication frame received in block 604 is a communication frame having a training signal that sounds a reverse MIMO channel. In block 608, the channel estimate from the second communication device to the first communication device, that is, the reverse channel estimate, is determined based on the communication frame received in block 604.
In block 612, the forward channel estimate, that is, the channel estimate from the first communication device to the second communication device, is determined based on the reverse channel estimate determined in block 604.
In block 616, the transmit beam formation vector, i.e., the beam formation vector for transmission over the forward channel, is determined based on the forward channel estimate determined in block 612.
At block 620, multiple communication frames, each requesting link quality information, are generated and transmitted to the second communication device. In one embodiment, each of the communication frames is transmitted using the beam forming vector determined in block 616. In one embodiment, each of the communication frames is transmitted using a different calibration matrix (eg, a calibration matrix that corrects a transmit / receive chain mismatch between the forward and reverse channels). In one embodiment, each of the communication frames is generated using the method described with reference to FIG. In one embodiment, the plurality of communication frames transmitted in block 620 are transmitted using the same MCS.
At block 624, the plurality of communication frames, each containing link quality information, are received from the second communication device in response to the plurality of communication frames being transmitted at block 620. In one embodiment, each of the communication frames received by block 620 is generated by the second communication device, such as by the method described with reference to FIG.
At block 628, the calibration matrix used for subsequent transmissions to other communication devices is determined based on the link quality information received at block 624. For example, in one embodiment, the calibration matrix that gives the highest SNR value is selected. As another example, in one embodiment, the calibration matrix that gives the highest link margin is selected. As another example, in one embodiment, the calibration matrix that gives the highest RSSI is selected. As another example, in one embodiment, a calibration matrix is generated using a set of beam forming vectors that gives the highest SNR value, link margin, RSSI, and so on. The calibration matrix determined in block 628 is used to send subsequent communication frames to the second communication device.
With reference to FIGS. 7 and 8 again, in one embodiment, a communication frame containing a request for link quality information is included in the multi-user communication frame. For example, in multi-user downlink transmission, a corresponding control field, including a request for link quality information, is included in each subframe corresponding to multiple client devices. Each of the client devices responds with link quality information in the corresponding uplink transmission. For example, in one embodiment, link quality information from a plurality of client devices is included in each confirmation notification frame. As another example, in multi-user downlink transmission, a control field containing a request for link quality information is included in the NDP announcement frame transmitted to multiple client devices. Each of the client devices responds with link quality information in the corresponding uplink transmission. For example, in one embodiment, link quality information from a plurality of client devices is included in each confirmation notification frame.
FIG. 12 is a timing chart 700 showing an exemplary transmission sequence in downlink multi-user MIMO. After the multi-user sounding / feedback process, the AP sends a multi-user packet 704 containing independent data to multiple client stations, including at least the first client (client 1) and the second client (client 2). Independent data destined for multiple client stations is transmitted simultaneously in different spatial streams, on different frequency parts of the channel, etc., in a suitable way. In one embodiment, packet 704 includes an indicator of MCS and / or link conformance feedback request. Packet 704 also includes an indicator of which client station should provide feedback. In the embodiment illustrated in FIG. 12, packet 704 includes an indicator that client 1 should provide MCS and / or link conformance feedback (eg, SNR). Client 1 sends MFB / link conformance feedback (eg SNR) in packet 708. In one embodiment, the MFB / link conformance feedback (eg SNR) is included in the control field of packet 708. In one embodiment, the MFB / link conformance feedback (eg SNR) is included in the MAC portion of packet 708 (eg the High Throughput Control (HTC) field). In another embodiment, the MFB is included in the control field of the PHY header portion of packet 708.
In one embodiment, packet 708 is a confirmation notification packet. In other embodiments, packet 708 is another packet suitable for transmitting MFB / link conformance feedback (eg, SNR) to the AP. For example, in one embodiment, packet 708 is a control wrapper frame. In another embodiment, packet 708 is a management frame.
FIG. 13 is a timing chart 750 showing other exemplary transmission sequences in downlink multi-user MIMO. During the multi-user sounding / feedback process, the AP sends null data packet announcement (NDPA) packet 754. In one embodiment, the NDPA packet 754 comprises an indicator of MCS and / or link conformance feedback (eg, SNR) requirements.
In one embodiment, the NDPA packet 754 indicates that all stations within the Basic Services Set (BSS) should provide feedback. In other embodiments, packet 754 also includes an indicator of which client station should provide feedback. In the embodiment illustrated in FIG. 13, packet 754 includes an indicator that client 1 and client 2 should provide MFB. For example, an indicator that client 1 and client 2 should provide MFB is the group ID of the group to which client 1 and client 2 belong.
Packet 754 indicates that after sounding / feedback processing, the client station should provide feedback in response to the subsequent multi-user downlink packet 758 being transmitted. Packet 758 contains independent data destined for multiple client stations, including at least a first client (client 1) and a second client (client 2). Independent data destined for multiple client stations is transmitted simultaneously in different spatial streams, on different frequency parts of the channel, etc., in a suitable way.
Client 1 sends MFB / link conformance feedback (eg SNR) in packet 762. In one embodiment, the MFB / link conformance feedback (eg, SNR) is included in the control field of packet 762. In one embodiment, the MFB / link conformance feedback (eg SNR) is included in the MAC portion of packet 762 (eg the High Throughput Control (HTC) field). In another embodiment, the MFB is included in the control field of the PHY header portion of packet 762.
Client 2 sends MFB / link conformance feedback (eg SNR) in packet 766. In one embodiment, the MFB / link conformance feedback (eg SNR) is included in the control field of packet 766. In one embodiment, the MFB / link conformance feedback (eg SNR) is included in the MAC portion of packet 766 (eg the High Throughput Control (HTC) field). In another embodiment, the MFB is included in the control field of the PHY header portion of packet 766.
In one embodiment, packets 762 and 766 are confirmation notification packets. In other embodiments, packets 762, 766 are other packets suitable for transmitting MFB / link conformance feedback (eg, SNR) to the AP. For example, in one embodiment, packets 762, 766 are control wrapper frames. In another embodiment, packets 762, 766 are management frames.
At least some of the various blocks, processes and techniques described above can be implemented using hardware, processors that execute firmware instructions, processors that execute software instructions, or any combination thereof. When implemented with a processor that executes software or firmware instructions, the software or firmware instructions are stored in any computer-readable memory. Such computer-readable memory includes magnetic disks, optical disks, other storage media, RAM, ROM, flash memory, processors, hard disk drives, optical disk drives, tape drives, and the like. Similarly, software or firmware instructions may be sent to the user or via a known or desired delivery method, including, for example, on a computer-readable disk or other portable computer storage mechanism, or via a communication medium, and the like. It may be delivered to the system. Typically, the communication medium embodies data represented by computer-readable instructions, data instructions, program modules, or other modulated data signals such as carrier waves or other transport mechanisms. The term "modulated data signal" means a signal having one or more features that have been set or modified to encode information within the signal. Communication media include, but are not limited to, wired networks such as wired networks or direct wired connections, as well as wireless media including acoustic, radio frequency, infrared and other wireless media. Thus, a software or firmware instruction may be a telephone line, DSL line, cable television line, optical fiber cable, (as considered to be equivalent or equivalent to providing software via a portable storage medium). It may be delivered to the user or system via a communication channel such as a wireless communication channel or the Internet. A software or firmware instruction is a machine that causes the processor to perform various actions when executed by the processor.
When implemented in hardware, the hardware may include one or more of independent components, integrated circuits, application specific integrated circuits (ASICs), programmable logic devices (PLDs), and the like.
Although the inventions of the present application have been described with reference to specific examples, these specific examples are for illustration purposes only and are not intended to limit the invention of the present application. Modifications, additions and / or deletions to the disclosed embodiments are possible without departing from the aspects of the present invention.
21 sheets
Sheet 1 Sheet 2 Sheet 3 Sheet 4 Sheet 5 Sheet 6 Sheet 7 Sheet 8 Sheet 9 Sheet 10 Sheet 11 Sheet 12 Sheet 13 Sheet 14 Sheet 15 Sheet 16 Sheet 17 Sheet 18 Sheet 19 Sheet 20 Sheet 21
Every citation, both ways
| Document | Relation | Office |
|---|---|---|
| JP2009512363A | Cites | Japan |
| JP2003324407A | Cites | Japan |
| JP2007295257A | Cites | Japan |
| WO2009055662A2 | Cites | World Intellectual Property Organization (WIPO) |
| JP2008526093A | Cites | Japan |
| JP2009540662A | Cites | Japan |
13 members in 6 offices
Priority claims29
| Document | Office | Kind | Date |
|---|---|---|---|
| 37932210 | United States of America | P | |
| 37932210 | United States of America | P | |
| 61379322 | United States of America | – | |
| 41185710 | United States of America | P | |
| 41185710 | United States of America | P | |
| 61411857 | United States of America | – | |
| 41615410 | United States of America | P | |
| 41615410 | United States of America | P | |
| 61416154 | United States of America | – | |
| 201161430379 | United States of America | P | |
| 201161430379 | United States of America | P | |
| 61430379 | United States of America | – | |
| 201161451431 | United States of America | P | |
| 201161451431 | United States of America | P | |
| 61451431 | United States of America | – | |
| 2011048795 | United States of America | W | |
| 2011048795 | United States of America | W | |
| 61379322 | – | – | – |
| 61411857 | – | – | – |
| 61416154 | – | – | – |
| 61430379 | – | – | – |
| 61451431 | – | – | – |
| US20100379322P | – | – | – |
| US20100411857P | – | – | – |
| US20100416154P | – | – | – |
| US2011048795 | – | – | – |
| US201161430379P | – | – | – |
| US201161451431P | – | – | – |
| WO2011US48795 | – | – | – |
Members13
| Document | Office | Kind | |
|---|---|---|---|
| US2012051246A1 | United States of America | A1 | |
| WO2012030585A2 | World Intellectual Property Organization (WIPO) | A2 | |
| WO2012030585A3 | World Intellectual Property Organization (WIPO) | A3 | |
| WO2012030585A3 | World Intellectual Property Organization (WIPO) | A3 | |
| CN103141046A | China | A | |
| EP2612461A2 | European Patent Office (EPO) | A2 | |
| KR20130098355A | Republic of Korea | A | |
| JP2013541882A | Japan | A | |
| JP6029110B2This record | Japan | B2 | |
| US9531498B2 | United States of America | B2 | |
| CN103141046B | China | B | |
| KR101829852B1 | Republic of Korea | B1 | |
| EP2612461B1 | European Patent Office (EPO) | B1 |
28 legal events, as the office reported them to INPADOC
Over the term
Point at a mark for the eventEvents
| Event | Code | |
|---|---|---|
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Written notification of registration of transferJAPANESE INTERMEDIATE CODE: R350R350 | R350 | |
| Request for change of ownership or part of ownershipJAPANESE INTERMEDIATE CODE: R313113S111 | S111 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Written notification of registration of transferJAPANESE INTERMEDIATE CODE: R350R350 | R350 | |
| Request for change of ownership or part of ownershipJAPANESE INTERMEDIATE CODE: R313113S111 | S111 | |
| Written request for registration of change of domicileJAPANESE INTERMEDIATE CODE: R313531S531 | S531 | |
| Written notification of registration of transferJAPANESE INTERMEDIATE CODE: R350R350 | R350 | |
| Request for change of ownership or part of ownershipJAPANESE INTERMEDIATE CODE: R313113S111 | S111 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Transfer withdrawnWithdrawnJAPANESE INTERMEDIATE CODE: R371R371 | R371 | |
| Request for change of ownership or part of ownershipJAPANESE INTERMEDIATE CODE: R313113S111 | S111 | |
| Receipt of annual feesJAPANESE INTERMEDIATE CODE: R250R250 | R250 | |
| Certificate of patent or registration of utility modelJAPANESE INTERMEDIATE CODE: R150R150 | R150 | |
| First payment of annual fees (during grant procedure)JAPANESE INTERMEDIATE CODE: A61A61 | A61 | |
| Written decision to grant a patent or to grant a registration (utility model)JAPANESE INTERMEDIATE CODE: A01A01 | A01 | |
| Decision of grant or rejection writtenTRDD | TRDD | |
| Request for written amendment filedJAPANESE INTERMEDIATE CODE: A523A521 | A521 | |
| Written request for extension of timeJAPANESE INTERMEDIATE CODE: A601A601 | A601 | |
| Written request for extension of timeJAPANESE INTERMEDIATE CODE: A601A601 | A601 | |
| Notification of reasons for refusalJAPANESE INTERMEDIATE CODE: A131A131 | A131 | |
| Request for written amendment filedJAPANESE INTERMEDIATE CODE: A523A521 | A521 | |
| Notification of reasons for refusalJAPANESE INTERMEDIATE CODE: A131A131 | A131 | |
| Report on retrievalJAPANESE INTERMEDIATE CODE: A971007A977 | A977 | |
| Written request for application examinationJAPANESE INTERMEDIATE CODE: A621A621 | A621 |
Numbers
- Publication
- 6029110
- Publication, DOCDB
- 6029110
- Publication, EPODOC
- JP6029110B
- Application
- 2013527115
- Application, DOCDB
- 2013527115
- Application, EPODOC
- JP20130527115
Titles2
- Japanese
- 通信ネットワークのリンク適合
- English
- Communication network link compatibility
Classification
- CPC, 2
- H04L1/0001
- H04L1/00
- IPC, 3
- H04L1 00
- H04J11 00
- H04J99 00
