Multiband reception device and communication method

Abstract

To provide a device for a multiband communication, and provide a method.SOLUTION: A multiband reception device comprises: a reception part that receives a plurality of MAC layer protocol data units (MPDUs) that belong to a single traffic identifier (TID) that is transmitted from a multiband transmission device in a plurality of frequency bands; and a transmission part that transmits a multiband block confirmation response frame indicating a reception state of each of the plurality of MPDUs containing one or more MPDUs transmitted in a certain frequency band on a first frequency band that is different from the frequency band. The transmission part transmits the block confirmation response frame in each band indicating a reception state of only MPDU transmitted in one frequency band in the plurality of frequency bands of the plurality of MPDUs belonging to the single TID in the one frequency band.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present embodiments relate generally to communication devices, and more particularly to methods and devices for multi-band communication involving multi-band traffic streams. [Background technology]

[0002] In today's world, communication devices are expected to operate wirelessly with the same capabilities as wired computing devices. For example, users expect to be able to seamlessly watch high-definition video streamed to their wireless communication devices. This presents challenges for communication devices and the access points to which they wirelessly connect.

[0003] Recently, the Institute of Electrical and Electronics Engineers (IEEE) 802.11 Group formed the Extreme High Throughput (EHT) Study Group to address the above challenges. Multi-band operation in the 2.4 GHz, 5 GHz, and 6 GHz frequency bands is considered a key candidate technology for such communications. Multi-channel aggregation across multiple bands is a natural way to increase communications data throughput many times over. In current IEEE 802.11 devices, if admission control for an access category (AC) by an access point (AP) is mandatory (e.g., via one or more Admission Control Mandatory (ACM) subfields in the Enhanced Distributed Channel Access (EDCA) parameter set element), the communicating device (STA) must set up a traffic stream (TS) for the AC with the AP (via an Add Traffic Stream (ADDTS) request / response exchange). A Block Ack agreement for the corresponding TID must also be made (via an Add Block Ack (ADDBA) request / response exchange). Summary of the Invention

[0004] One non-limiting, exemplary embodiment provides a multi-band communications device including at least a plurality of transceivers, each of which, in operation, transmits signal frames in a different one of a plurality of frequency bands, and a media access control (MAC) circuit, coupled to the transceivers and, in operation, receiving, in one of the plurality of frequency bands, a multi-band block acknowledgment frame that acknowledges the signal frames transmitted in the plurality of frequency bands.

[0005] Another non-limiting, exemplary embodiment contributes to providing a multi-band communications device including a plurality of transceivers and a media access control (MAC) circuit that, in operation, generates a multi-band block acknowledgment frame that acknowledges signal frames received over a plurality of frequency bands and transmits the multi-band block acknowledgment frame over one of the plurality of frequency bands.

[0006] It should be noted that the general or specific embodiments may be implemented as a system, a method, an integrated circuit, a computer program, a storage medium, or any selective combination thereof. Additional benefits and advantages of the disclosed embodiments will become apparent from the specification and drawings. These benefits and / or advantages may be obtained individually by various embodiments and features of the specification and drawings. However, not all of these features need to be present to obtain one or more of such benefits and / or advantages. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing an example of an overview of an 802.11 wireless network basic service set (BSS) according to an embodiment of the present invention. [Figure 2] FIG. 1 is a diagram showing an example of communication from an access point (AP) to a communication device according to an embodiment of the present invention. [Figure 3]FIG. 1 illustrates an example of setting up a traffic stream (TS) and a block acknowledgment (BA) agreement for a traffic identifier (TID) according to an embodiment of the present invention. [Figure 4] 1 illustrates a communication flow between a multi-band AP 102 and a multi-band STA 104 for the setup and subsequent communication of TSs and BAs across multiple bands in accordance with current multi-band communication. [Figure 5] FIG. 1 illustrates the communication flow between a multiband AP 102 and a multiband STA 104 for the setup of a multiband TS and a multiband BA and subsequent communication, according to an embodiment of the present invention. [Figure 6] FIG. 1 illustrates an example of a multi-band enhanced distributed channel access (EDCA) parameter set element according to the present embodiment. [Figure 7] 1 shows an example of a multiband ADDTS request frame and a multiband ADDTS response frame according to the present embodiment. [Figure 8] 1 is a diagram showing an example of a multi-band ADDBA request frame and a multi-band ADDBA response frame according to the present embodiment. [Figure 9] FIG. 9 shows examples of multiband elements in FIGS. 7 and 8 according to the present embodiment. [Figure 10] FIG. 1 shows an example of a multi-band capability element according to the present embodiment. [Figure 11] FIG. 10 shows examples of a multiband BlockAckReq frame and a multiband BlockAck frame according to a first modification of the present embodiment. [Figure 12] FIG. 1 illustrates an example of a traffic stream and Block Ack architecture according to an embodiment of the present invention. [Figure 13] FIG. 1 is a diagram illustrating a first exemplary multi-band transmission example according to the present embodiment. [Figure 14] FIG. 1 illustrates an example of an exemplary reference model for implementing Multiband Block Ack according to an embodiment of the present invention. [Figure 15]FIG. 10 is a diagram illustrating a second exemplary multi-band transmission example according to the present embodiment. [Figure 16] FIG. 10 is a diagram showing an example of a multiband BlockAckReq frame in which a multiband frame variant type according to the present embodiment is defined. [Figure 17] FIG. 10 is a diagram illustrating an example of a multi-band BlockAck frame in which variants of the BA Information field are defined according to the present embodiment. [Figure 18] FIG. 15 illustrates an example of a first variation of the exemplary reference model for the Multiband Block Ack implementation of FIG. 14 according to an embodiment of the present invention. [Figure 19] FIG. 10 is a diagram illustrating an example of a delayed Block Ack scheme as a third exemplary multi-band transmission according to the present embodiment. [Figure 20] FIG. 1 illustrates an example of the purpose of the traffic stream and Block Ack architecture defined to handle multi-band transmissions and multi-band Block Acks, according to an embodiment. [Figure 21] FIG. 10 shows examples of a multiband BlockAckReq frame and a multiband BlockAck frame according to a second modification of the present embodiment. [Figure 22] FIG. 15 illustrates an example of a second variation of the exemplary reference model for the Multiband Block Ack implementation of FIG. 14 according to an embodiment of the present invention. [Figure 23] FIG. 10 is a diagram illustrating an example of an implicit multiband block Ack request scheme as a fourth exemplary multiband transmission according to the present embodiment. [Figure 24] 1 is a simplified block diagram of a multi-band communication device according to an embodiment of the present invention. [Figure 25] 1 is a detailed block diagram of a multi-band communication device according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0008] In the accompanying drawings, like reference numerals refer to identical or functionally similar elements throughout the different views, and together with the following detailed description, which are incorporated in and form a part of this specification, serve to illustrate various embodiments and explain various principles and advantages of the present embodiments. Those skilled in the art will appreciate that the elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale.

[0009] The following detailed description is merely exemplary in nature and is not intended to limit the embodiments or the application and uses of the embodiments. Furthermore, there is no intention to be bound by the preceding background or any theory presented in this detailed description. It is recognized that existing IEEE 802.11 Traffic Stream (TS) and Block Ack (BA) mechanisms for a particular TID are limited to a single band. An objective of the present embodiments is to present a TS and BA mechanism that operates across multiple bands to fully realize the throughput gains of multi-band aggregation. Furthermore, other desirable features and characteristics will become apparent from the following detailed description and the appended claims, taken in conjunction with the accompanying drawings and the background of this disclosure.

[0010] Referring to FIG. 1, an example overview of an 802.11 wireless network 100, also known as a basic service set (BSS), is shown. The 802.11 wireless network 100 includes an access point (AP) 102, which is a redistribution point, and multiple communication devices (STAs) 104 connected to the AP 102. Current IEEE 802.11 BSSs operate in a single frequency band with multi-band-capable APs operating as independent APs in each frequency band. While most current 802.11 STAs are single-band devices, future 802.11 communication devices (e.g., very high throughput (EHT) communication devices) are expected to be able to operate simultaneously in multiple frequency bands. Such a future AP 102 may set up BSSs in the 2.4 GHz frequency band, the 5 GHz frequency band, or the 6 GHz frequency band as separate BSSs, as in existing 802.11 systems, with STAs 104 assumed to participate in the BSSs in the three frequency bands according to legacy authentication and association procedures. Alternatively, the future AP 102 may operate a unified / virtual BSS operating in multiple frequency bands (i.e., the 2.4 GHz frequency band 106, the 5 GHz frequency band 108, and the 6 GHz frequency band 110), as shown in BSS 100. In this case, STAs 104 are assumed to participate in the unified / virtual BSS 100 in all three frequency bands via individual authentication and association requests / responses in each frequency band or via multi-band authentication and association requests / responses in any one of these frequency bands.

[0011] FIG. 2 illustrates an example 200 of communication of a video file 202 from an AP 102 to a STA 104. To fully realize the throughput gains of multi-band aggregation, a traffic stream (TS) and block acknowledgement (BA) mechanism that operates across multiple bands is desirable. Such multi-band TS and BA can help increase device throughput many times by enabling aggregation of traffic across multiple bands (e.g., 2.4 GHz band 204, 5 GHz band 206, and 6 GHz band 208). Streaming high-resolution video 202 (e.g., high-definition (HD) or 4K or 8K video) may require such multi-band transmission. At the Internet Protocol (IP) layer 210 of the AP 102, the video file 202 is segmented into small IP packets. The 802.11 media access control (MAC) layer 212 of the AP 102 converts the IP packets into 802.11 MAC layer protocol data units (MPDUs) and sends them to a MAC TX queue 214, which then provides the MPDUs to transceivers 216, 218, and 220 in the lower MAC layer 212 and physical layer (PHY) 222 for simultaneous transmission over the 2.4 GHz frequency band 204, the 5 GHz frequency band 206, and the 6 GHz frequency band 208, respectively. In this manner, MPDU 224 is transmitted over the 2.4 GHz frequency band 204, MPDU 226 over the 5 GHz frequency band 206, and MPDU 228 over the 6 GHz frequency band 208 to the receiving device, the STA 104.

[0012] At the receiving device, the MPDUs 224, 226, 228 are received by the transceivers 230, 232, 234 at the PHY layer 236 and the lower MAC layer 238. The MPDUs 224, 226, 228 are collected by the MAC layer 238 and reordered, if necessary, to their original order before being passed to the MAC RX queue 240 and to the IP layer 242 where the IP packets are combined to form the original video file 202.

[0013] In current 802.11 communication devices, admission control is typically mandated to maintain quality of service (QoS) levels for high-priority traffic such as video (AC_VO) or voice (AC_VI). When admission control for an access category (AC) is mandated by the AP (e.g., via the admission control required (ACM) subfield in the enhanced distributed channel access (EDCA) parameter set element), the STA must set up a TS for the access category (AC) with the AP through an add traffic stream (ADDTS) request / response exchange. The traffic specification (TSPEC) element in the ADDTS request and ADDTS response frames specifies various parameters associated with the TS, including the traffic stream identifier (TSID), direction, MSDU size, minimum and maximum interval range, and minimum, average, and peak data rates.

[0014] Also, Block Ack agreement for the corresponding TID must occur via Add Block Ack (ADDBA) Request / Response exchange. Traffic streams and Block Ack agreements may be set up for different frequency bands by including multi-band elements in each ADDTS and ADDBA Request / Response exchange, or via On-Channel Tunneling (OCT).

[0015] Because the unmanaged addition of new high-priority traffic to a wireless network can adversely affect the QoS of existing traffic, APs typically mandate admission control for such traffic. In the presence of a large amount of existing traffic, an AP may reject a STA's request to set up a traffic stream for that access category (AC).

[0016] To achieve multi-band transmission according to this embodiment, modifications to the operation of TS and BA are required since the current TS and BA setup is set up between the MAC layer of a specific band. Referring to Figure 3, an example 300 shows a traffic stream (TS) and Block Ack (BA) agreement for a traffic identifier (TID) set up between a transmitter (TX) communication device 302 and a receiver (RX) communication device 304 according to this embodiment. The TS and BA agreements are typically set up as a pair, with the BA agreement being set up in the opposite direction to the TS direction. TSs 306, 308, and 310 are set up between the TX MAC layers 318, 320, and 322 of each band and the corresponding RX MAC layers 324, 326, and 328 of each band for data transmission from the transmitter 302 to the receiver 304, while BA agreements 312, 314, and 316 are set up in the opposite direction between the RX MAC layers 324, 326, and 328 and the TX MAC layers 318, 320, and 322 for transmission of BAs from the receiver to the transmitter, acknowledging the data transmissions corresponding to TSs 306, 308, and 310, respectively.

[0017] On the transmitter side, the TX Upper Layer 330 and TX Logical Link Control (LLC) Layer 332 decide which band to use for transmission for a particular TID. MPDUs for each TS 306, 308, and 310 are generated at the TX MAC layer (MAC Layers 318, 320, and 322) for each band and addressed to the peer RX MAC layer (MAC Layers 324, 326, and 328) for the same band. On the receiver side, MAC Service Data Units (MSDUs) received on different bands are reordered by the RX LLC Layer 334 and passed to the RX Upper Layer 336. Block Acknowledgments (BAs) corresponding to the MPDUs for each TS 306, 308, and 310 are generated at the RX MAC layer (MAC Layers 324, 326, and 328) for the same band and addressed to the peer TX MAC layer (MAC Layers 318, 320, and 322) for the same band. If a BA is not received or if an MPDU is not acknowledged in the BA bitmap (the bit corresponding to the MPDU is set to 0), the transmission is considered to have failed for the unacknowledged MPDU. MAC layer retransmissions of the unacknowledged MPDU are performed in the same frequency band as the failed transmission (2.4 GHz, 5 GHz, 6 GHz), as shown in Figure 4.

[0018] FIG. 4 illustrates a communication flow 400 between a multi-band AP 102 and a multi-band STA 104 for TS and BA setup and subsequent communication according to current multi-band communication. If an EDCA parameter set element received in a beacon frame in a given band has the Admission Control Required (ACM) bit set for a given access category (AC), the STA must set up a traffic stream (TS) for that TID with the AP before transmitting data frames belonging to the corresponding TID / AC in that band. TS setup 410 for a specific TID is performed separately for each band by exchanging ADDTS request / response frames in each band, e.g., for downlink data transmission (i.e., transmission from the AP to a non-AP device). The ADDTS request is always initiated by a non-AP STA, regardless of the actual direction of data transmission. Similarly, BA setup 420 for a specific TID is performed separately for each band by exchanging ADDBA request / response frames in each band. The ADDBA request is initiated by the transmitter device of the corresponding TS (in this case, the AP). Once a TS and BA are set up in each band, a data transmission and corresponding BA transmission may occur in each band (e.g., transmission 430 may occur in the 6 GHz band, transmission 440 may occur in the 5 GHz band, and transmission 450 may occur in the 2.4 GHz band). BlockAck frames for data transmissions 430, 440, and 450 in each band are requested via BlockAckReq frames, and the requested BlockAck frames are transmitted in the same band. Because transmissions 430, 440, and 450 occur in different bands, these transmissions may occur simultaneously or at overlapping times, thereby achieving multi-band transmission.

[0019] If the transmission of a data frame is determined to be unsuccessful (eg, as indicated in a BlockAck frame in data transmission 452), the data frame is retransmitted (eg, retransmission 454) on the same bandwidth.

[0020] Although multi-band transmission can be achieved with this approach, scheduling, band selection, retransmission, and other responsibilities are delegated to higher layers 330, 336 (FIG. 3), which may not have the necessary information of the PHY layers 317, 319, 321, 323, 325, 327 to make such decisions. It would be better if the multi-band transmission decision were made at the MAC layer 318, 320, 322, 324, 326, 328, since the MAC layer has better information / control of the PHY layer.

[0021] FIG. 5 illustrates a communication flow between a multi-band AP 102 and a multi-band STA 104 for TS and BA setup and subsequent communication according to this embodiment. A multi-band-capable STA 104 can choose to listen to beacon frames transmitted in a single band to conserve power. Aside from legacy EDCA parameter set elements, a beacon frame 502 in a primary band (e.g., the 5 GHz band) can carry a multi-band EDCA parameter set element to indicate EDCA parameters for bands other than the band in which the beacon frame 502 is transmitted. If the ACM bit in the beacon frame 502 is set to “1” for any AC in any band, the STA 104 must set up a traffic stream (TS) for that TID in that band before transmitting data frames belonging to the TID / AC corresponding to that AC in the indicated band. Alternatively, the STA 104 may receive beacon frames in each band separately using legacy EDCA parameter set elements carrying the ACM bit set to “1.”

[0022] If both the transmitter and receiver support multi-band TS and multi-band BA and indicate the capability in the multi-band TS and Block Ack fields in the multi-band capability element (the multi-band capability element including the Multi-band TS and Block Ack fields is discussed in more detail in FIG. 10 ), multi-band TS setup 510 (e.g., setup for downlink traffic) for a specific TID applicable to multiple bands (e.g., three bands, 2.4 GHz, 5 GHz, and 6 GHz) may be performed using a single frame exchange (e.g., a channel in the primary band) according to this embodiment. Similarly, multi-band BA setup 520 for a TID applicable to multiple bands (e.g., three bands, 2.4 GHz, 5 GHz, and 6 GHz) may be performed using a single frame exchange (e.g., a channel in the primary band) according to this embodiment. Multi-band ADDTS request frame 512 and multi-band ADDTS response frame 514 are used to negotiate TS setup 516 for TIDs across multiple bands. Similarly, a multi-band ADDBA request 522 and a multi-band ADDBA response 524 are used to negotiate a BA setup 526 for a TID across multiple bands. In this downlink traffic example, the multi-band ADDBA request 522 is sent by the AP 102 to the STA 104. If the multi-band TS setup 510 were for uplink traffic, a multi-band ADDBA request would be sent in the opposite direction, i.e., by the STA 104 to the AP 102.

[0023] Once the multi-band TS 516 and multi-band BA 526 are set up on multiple bands, the AP 102 can proceed to initiate multi-band transmission 530 to the STAs 104. The multi-band transmission 530 includes simultaneously transmitting frames belonging to the same TS (TID / AC) in QoS data A-MPDUs 536a, 536b, and 536c, respectively, on the three bands to the STAs 104.

[0024] Upon completion of the multi-band transmission 530, the AP 102 may transmit a multi-band BlockAckReq 532 to the STA 104 in one of these bands (e.g., the primary band) to request a multi-band Block Ack acknowledging the frames 536a, 536b, and 536c received in the three bands. Upon receiving the multi-band BlockAckReq 532 from the AP, the STA 104 transmits a multi-band Block Ack 534 in the same band in which the multi-band BlockAckReq 532 was received, indicating that the STA successfully received the QoS data A-MPDUs 536a and 536b but failed to receive the QoS data A-MPDU 536c transmitted in the 2.4 GHz band. To improve the success rate of retransmissions by using frequency diversity, the AP 102 may, in accordance with the present embodiment, choose to retransmit the QoS data A-MPDU 538 in the 6 GHz band instead of the 2.4 GHz band used for the original transmission.

[0025] The AP 102 then transmits a Multi-band BlockAckReq 542 to the STA 104 on a different band (e.g., the primary band) requesting a Multi-band Block Ack 544 carrying an aggregated BA bitmap acknowledging the frame received on the 6 GHz band. Thus, according to this embodiment, it can be seen that a traffic stream is set up across multiple bands using a single multi-band ADDTS frame exchange 512, 514 on any one band. Block Acks are also set up across multiple bands using a single multi-band ADDBA frame exchange 522, 524 on any one band. Furthermore, according to this embodiment, the aggregated Multi-band Block Ack frame 534 acknowledges a transmission with multi-band aggregation, the Multi-band Block Ack frame 544 may be used to acknowledge a transmission on another band, and a failed frame 536c may be retransmitted 538 on a different band.

[0026] Thus, in accordance with the present embodiment, a multi-band communications device (e.g., AP 102) includes multiple transceivers 216, 218, and 220, each of which, in operation, transmits signal frames 536c, 536a, and 536b in a different one of multiple frequency bands 204, 206, and 208. The multi-band communications device also includes a media access control (MAC) circuit 212 coupled to the multiple transceivers 216, 218, and 220, which, in operation, generates a multi-band block acknowledgment request frame 532 and transmits the MAC multi-band block acknowledgment request frame 532 in one of the multiple frequency bands 206 to request a multi-band block acknowledgment frame 534. The media access control (MAC) circuit 212 then receives, in one of the multiple frequency bands 206, the multi-band block acknowledgment frame 534 that acknowledges the signal frames 536a, 536b, and 536c transmitted in the multiple frequency bands.

[0027] Further according to this embodiment, the multi-band communications device (e.g., the STA 104) includes a plurality of transceivers 230, 232, and 234 coupled to the MAC circuit 238. In operation, each of the plurality of transceivers 230, 232, and 234 receives signal frames 536a, 536b, and 536c over a different one of the plurality of frequency bands 204, 206, and 208. In operation, the MAC circuit 238 receives a multi-band block acknowledgment request frame 532 over one frequency band 206 of the plurality of frequency bands, generates a multi-band block acknowledgment frame 534 that acknowledges the signal frames 536a, 536b, and 536c received over the plurality of frequency bands 204, 206, and 208, and transmits the multi-band block acknowledgment frame 534 over the one frequency band 206 of the plurality of frequency bands.

[0028] FIG. 6 illustrates an example 600 of a multi-band EDCA parameter set element 610 in a beacon frame 402 (FIG. 4) according to this embodiment. The multi-band EDCA parameter set element 610 indicates EDCA parameters for bands other than the band in which the beacon frame 402 is transmitted. The applicable bands are indicated by a Band ID field 612. The format of each Parameter Record field 620 for a particular AC is shown. If the ACM bit 622 is set to "1" for any AC in any band, the STA must set up a traffic stream (TS) for that TID in that band before transmitting data frames belonging to the TID / AC corresponding to that AC in the indicated band. Alternatively, the STA may receive beacon frames in each band separately that include a legacy EDCA parameter set element carrying the ACM bit 622 set to "1."

[0029] Figure 7 shows an example 700 of a multi-band ADDTS request frame 710 and a multi-band ADDTS response frame 720 according to this embodiment, and Figure 8 shows an example 800 of a multi-band ADDTS request frame 810 and a multi-band ADDTS response frame 820 according to this embodiment. The multi-band ADDTS request frame 710 and the multi-band ADDTS response frame 720 are used to negotiate TS setup for a TID across multiple bands according to information in one or more multi-band elements 750 in each of the multi-band ADDTS request frame 710 and the multi-band ADDTS response frame 720. Similarly, the multi-band ADDBA request frame 810 and the multi-band ADDBA response frame 820 are used to negotiate BA setup for a TID across multiple bands according to information in one or more multi-band elements 750 in each of the multi-band ADDTS request frame 810 and the multi-band ADDTS response frame 820.

[0030] 9, example 900 illustrates a multi-band element 750 according to this embodiment. The multi-band element 750 indicates an additional band (separate from the band in which the transmission occurs) to which the TS or BA agreement applies. The multi-band element 750 may also include a MAC address to be used in that band.

[0031] The multi-band element 750 includes a multi-band control field 910, which in turn includes several fields, including an inter-band field 920. The inter-band field 920 is used to distinguish the multi-band element for use in multi-band TS and BA setups. When the inter-band field 920 is set to '1', this indicates that the corresponding setup applies to the band indicated in the band ID field 930, in addition to the band in which the frame carrying the element is transmitted. Thus, the inter-band field 920 helps distinguish between the inclusion of the multi-band element 750 for multi-band ADDTS and multi-band ADDBA setups according to this embodiment and its use for conventional ADDTS and ADDBA setups performed in a different band.

[0032] 7 and 8, each of the multi-band ADDTS request frame 710, multi-band ADDTS response frame 720, multi-band ADDBA request frame 810, and multi-band ADDBA response frame 820 includes two multi-band elements 750, with the inter-band field 920 set to "1," the first multi-band element 750 having the band ID field 930 set to 2.4 GHz, and the second multi-band element 750 having the band ID field 930 set to 6 GHz. Because the frames are transmitted in the 5 GHz band, this indicates a multi-band setup with three bands.

[0033] In this example, a multi-band ADDBA request 810 is sent by the AP 102 to the STA 104, whereas if the multi-band TS setup 510 were for uplink traffic, the multi-band ADDBA request would be sent by the STA 104 to the AP 102. Once the TS and BA are configured on the multi-band, the AP 102 can proceed to initiate a multi-band transmission 530 to the STA 104. The multi-band transmission 530 involves simultaneous transmission of frames belonging to the same TS (TID / AC) to the STA 104 across three bands.

[0034] 10 illustrates an example 1000 of a multiband capability element 1010 according to this embodiment. If both the transmitter and receiver support multiband TS and multiband BA and indicate the capability in the multiband TS and Block Ack field 1020 in the multiband capability element 1010, multiband TS setup 510 (downlink traffic) and multiband BA setup 520 for a specific TID applicable to multiple bands may be performed using a single frame exchange, for example, on a channel in the primary band. The multiband TS and Block Ack field 1020 also indicates whether the AP 102 and the STAs 104 support the multiband TS and multiband BA functionality, and the supported bands field 1030 indicates the frequency bands supported by the AP 102 and the STAs 104.

[0035] 11 shows examples of a multi-band BlockAckReq frame 1100 and a multi-band BlockAck frame 1150 according to a first variation of this embodiment. After completing the multi-band transmission 530, the AP 102 can transmit the multi-band BlockAckReq frame 1100 to a STA in any band (e.g., the primary band) to request a multi-band BlockAck frame 1150. The multi-band BlockAck frame 1150 includes an integrated BA bitmap in a BA Information field 1152 to acknowledge frames received in the three bands. The multi-band field 1110 and the multi-band field 1160 distinguish the multi-band BlockAckReq frame 1100 and the multi-band BlockAck frame 1150 from the prior art single-band BlockAckReq frame and the prior art single-band BlockAck frame, respectively.

[0036] The integrated BA bitmap in the multi-band BlockAck frame 1150 indicates that the receiver failed to receive the QoS data A-MPDU 536c transmitted in the 2.4 GHz band. To improve the success rate of retransmission by using frequency diversity, the AP 102 can choose to retransmit the QoS data A-MPDU 538 in the 6 GHz band instead of the 2.4 GHz band used for the original transmission.

[0037] The AP 102 then transmits a multi-band BlockAckReq frame 1100 to the STA 104 on a different band (e.g., the primary band) to request a multi-band BlockAck frame 1150 carrying an aggregate BA bitmap acknowledging the frame received on the 6 GHz band.

[0038] The Receiver Address (RA) and Transmitter Address (TA) fields are set as the MAC addresses of the wireless radio interfaces for each band. However, regardless of the contents of the RA and TA fields, if the multiband field 1110 is set to "1," the BlockAckReq frame 1100 is interpreted as requesting a multiband BlockAck frame that acknowledges frames belonging to the TID indicated in the TID_INFO field 1112, regardless of the band on which the frames are received. Similarly, regardless of the contents of the RA and TA fields, if the multiband field 1160 is set to "1," the multiband BlockAck frame 1150 carries an integrated BA bitmap in the BA Information field 1152 that acknowledges frames belonging to the TID indicated in the TID_INFO field 1162, regardless of the band on which the frames are received.

[0039] Therefore, in accordance with this embodiment, traffic belonging to the same TID may be split across multiple bands. Furthermore, Block Acks for multiple bands may be aggregated and transmitted in another band. This capability is provided in accordance with this embodiment for existing Block Ack Request types, such as the Compressed Block Ack Request type, the Multi-TID Block Ack Request type, the Multi-STA Block Ack Request type, and the GroupCast with Retry (GCR) Block Ack Request type.

[0040] 12 illustrates an example traffic stream and Block Ack architecture 1200 according to this embodiment. The MAC layers 318, 320, 322, 324, 326, and 328 are divided into band-independent Unified Upper MAC (UMAC) layers 1202 and 1204 and band-specific Lower MAC (LMAC) layers 1206, 1208, 1210, 1212, 1214, and 1216. Multi-band traffic stream agreements 1220, 1222, and 1224 and multi-band Block Ack agreements 1230, 1232, and 1234 for TIDs are set up between the respective MAC layers for each band.

[0041] The upper layer 330 and LLC layer 332 may interact with the unified UMAC layer 1202, and the upper layer 336 and LLC layer 334 may interact with the unified UMAC layer 1204. At the transmitter 302 side, the unified UMAC layer 1202 performs multi-band aggregation of TS data across the three TS data paths 1240, 1242, and 1244 (i.e., aggregation of frames belonging to a particular traffic stream (TS) may occur across different bands) and determines which bands to use for transmission and retransmission. The actual bands used for transmission may be transparent to the upper layers. The unified UMAC 1204 at the receiver 304 is responsible for multi-band de-aggregation (i.e., reordering frames belonging to a particular traffic stream (TS) received from different bands) and recording reception in the integrated block Ack scorecard.

[0042] The unified UMAC 1204 of the receiver 304 is also responsible for multi-band Block Ack generation and transmission of multi-band Block Acks (BAs) along a multi-band BA path 1250 in a selected frequency band (2.4 GHz in this example). The transmitter 302 may request a multi-band BA in any band by transmitting a multi-band Block Ack request. The receiver 304 generates and transmits a multi-band Block Ack in response to receiving a multi-band Block Ack request frame or in response to an implicit request to generate a multi-band Block Ack frame. The multi-band Block Ack frames are transmitted in the same band in which the respective request was received.

[0043] 13 illustrates a first exemplary multi-band transmission example 1300 according to this embodiment, showing transmissions in a first frequency band 1302 (e.g., 2.4 GHz), a second frequency band 1304 (e.g., 5 GHz), and a third frequency band 1306 (e.g., 6 GHz), assuming that TS and BA setup for TIDs has been completed in those bands. The bandwidth of the channels in each band 1302, 1304, 1306 may vary depending on channel conditions and availability (e.g., 20 MHz for the 2.4 GHz band 1302, 80 MHz for the 5 GHz band 1304, and 160 MHz for the 6 GHz band 1306). Band 1 (1302) (e.g., the 2.4 GHz band) may be primarily used to exchange management and control frames such as multi-band block acknowledgment request frames 1308 and multi-band block acknowledgment frames 1310 and is known as the primary band, while band 2 (1304) (e.g., the 5 GHz band) and band 3 (1306) (e.g., the 6 GHz band) may be primarily used to exchange data frames 1312 (e.g., downlink (DL) PPDUs) and are known as secondary or supplemental bands.

[0044] After gaining access to a channel in each band, the AP 102 begins a multi-band transmission 1300 consisting of a downlink PPDU 1312a in Band 3 (1306), a downlink PPDU 1312b in Band 2 (1304), and a downlink PPDU 1312c in Band 1 (1302). Each PPDU may contain aggregated MPDUs (A-MPDUs), each having several frames.

[0045] The AP 102 sets the Ack Policy in the QoS Control field of each frame to Block Ack to indicate that there should be no immediate Ack in each band, allocates BAR and BA transmissions in the low-rate band (e.g., 2.4 GHz band 1302), and reserves the high-rate bands (e.g., band 2 (1304) and band 3 (1306)) for data transmission. Furthermore, the same sequence number counter is used for each STA, TID pair across multiple bands to ensure that the sequence numbers (SNs) of transmitted frames do not overlap across bands. In this example, frames for SN1, SN2, and SN3 are transmitted in band 1 (1302) in PPDU 1312c, frames for SN4, SN5, and SN6 are transmitted in band 2 (1304) in PPDU 1312b, and frames for SN7, SN8, and SN9 are transmitted in band 3 (1306) in PPDU 1312a. The STA 104 (i.e., receiver) maintains a separate BlockAck bitmap for each band in its network interface (NIC), but upon receiving a multi-band BlockAckReq frame, it aggregates the separate BlockAck bitmaps into a single BlockAck bitmap 1314. The multi-band BA frame 1310 includes an aggregate bitmap 1314 that acknowledges frames received on the three bands (in which a bit set to "1" indicates successful frame reception for the frame with the corresponding SN, and a "0" indicates unsuccessful frame reception for the frame with the corresponding SN).

[0046] In the example transmission 1300, the multi-band aggregated DL PPDU frame transmission includes frame 1312a transmitted in band 3 (1306), frame 1312b transmitted in band 2 (1304), and frame 1312c transmitted in band 1 (1302), with SN2's frame transmission in band 1 (1302) and SN5 and SN6's frame transmission in band 2 (1304) failing. Upon completion of the multi-band transmission, the AP 102 transmits a multi-band BlockAckReq frame 1308a to request the multi-band BA to acknowledge the frames transmitted in the three bands 1302, 1304, and 1306. The multi-band BA 1310a aggregates the BlockAck bitmaps from the three bands into an aggregated BlockAck bitmap 1314a. Bits 2, 5, and 6 corresponding to SN2, SN5, and SN6 are set to "0" in the consolidated BlockAck bitmap 1314a to indicate failed reception of the frames for SN2, SN5, and SN6, while the remaining bits are set to "1" to indicate successful reception. Because there are failed transmissions in Band 2 (1304) and Band 1 (1302) but no failures in Band 3 (1306), the AP 102 may determine that the channel conditions in Band 3 are better and choose to consolidate the failed frames and retransmit them in Band 3 (1306) in PPDU 1312d. A multi-band BlockAckReq frame 1308b is then transmitted in Band 1 (1302) requesting a multi-band BA 1310b carrying an acknowledgment for the frames carried in the PPDU 1312d transmitted in Band 3 (1306). This time, all three retransmitted frames are received successfully, and the STA 104 transmits a multi-band BA 1310b with the corresponding bit in the BA bitmap set to one.

[0047] 14 illustrates an example reference model 1400 for implementing multi-band Block Ack in accordance with this embodiment. In a wireless communication device, the radio interface (I / F) for each band is typically implemented as an independent module (e.g., modules 1410, 1420, and 1430 (e.g., transceiver units 216, 218, and 220 (FIG. 2)) for the 2.4 GHz, 5 GHz, and 6 GHz bands, respectively). All of modules 1410, 1420, and 1430 are connected to a host system 1405, which may be a CPU. The time-critical MAC functions within the physical layer (PHY) modules (e.g., 317, 319, 321 (FIG. 12)) and lower MAC layer 1402 (e.g., 1206, 1208, 1210 (FIG. 12)) may be implemented in the wireless I / Fs 216, 218, 220, and the remaining MAC functions (i.e., upper MAC layer 1404 (e.g., 1202 (FIG. 12))) may be implemented in the host system 1405.

[0048] Because BAs corresponding to BARs must be generated with low latency (i.e., within the short interframe space (SIFS) from the end of the BAR), the Block Ack scorecard for a specific band is implemented using fast but expensive on-chip memory within each radio interface. However, maintaining a BA scorecard that persists throughout the duration of all active Block Ack sessions (known as full state Block Ack) increases the memory requirements for the receiver implementation. Therefore, in most implementations, the on-chip memory is reused for multiple Block Ack sessions. The memory acts as a cache to store the state of the last active Block Ack session (also known as partial state Block Ack). In-band BA scorecards 1412, 1422, and 1432 are examples of on-chip memory used as BA scorecards to record the reception status of frames received in the 2.4 GHz, 5 GHz, and 6 GHz bands, respectively. Partial State Block Acks save memory, but increase the risk that the Block Ack scorecard may be overwritten by another Block Ack session at the next Transmission Opportunity (TXOP), requiring special handling to prevent data loss.

[0049] To implement Multi-band Block Ack operations, a Multi-band BA Scorecard 1406 is maintained in the host system 1405. Because memory in the host system 1405 is generally inexpensive, the Multi-band BA Scorecard 1406 may be implemented as a full-state Block Ack scorecard (i.e., the scorecard persists for the entire duration of the Multi-band Block Ack session).

[0050] According to this embodiment, as shown in example 1400, frames received in each band are parsed by Rx parsers 1414, 1424, 1434 and processed according to frame type. Data frames 1415, 1425, 1435 that are correctly received and correctly addressed to the receiver are recorded in in-band BA scorecards 1412, 1422, 1432 according to the data frame sequence number (SN) before being passed to receive buffer 1408. The contents of receive buffer 1408 may be periodically sorted according to data frame SN.

[0051] In conventional single-band Block Ack operation, upon completion of a TXOP (for implicit Block Ack) or upon receiving a legacy Block Ack Request (BAR) frame (for explicit Block Ack), the subordinate MAC copies the BA bitmap from the in-band BA scorecard and generates a Block Ack frame for immediate transmission. However, for multi-band Block Ack operation, explicit Block Ack may be used, and upon completion of a TXOP on each band, the multi-band BA scorecard 1406 is updated with the contents of the in-band scorecards 1412, 1422, and 1432 from the respective radio I / Fs. By the end of the multi-band transmit opportunity (TXOP), the multi-band BA scorecard 1406 may combine the BA bitmaps of all in-band BA scorecards 1412, 1422, and 1432.

[0052] Finally, upon receiving a multi-band BAR frame 1416 on either band, the upper MAC 1404 copies the BA bitmap from the multi-band BA scorecard 1406 and generates 1407 a multi-band BlockAck frame for transmission. At the same time, the reception of the multi-band BAR frame 1416 triggers the upper MAC to reassemble complete MSDUs from the frames in the receive buffer 1408 (all complete MSDUs with a starting sequence number (SSN) less than the SSN carried in the multi-band BAR frame 1416) and forward them in order to the upper layer. In the example 1400, the reception of the multi-band BAR frame 1416 and the transmission of the multi-band BA frame 1820 are shown in the 2.4 GHz band, but it will be understood that the process is the same for other frequency bands.

[0053] 15 illustrates a second exemplary multi-band transmission example 1500 according to this embodiment. This second exemplary multi-band transmission is similar to the first exemplary multi-band transmission (FIG. 13), except that it is an example of a frequency division duplex (FDD) scenario in which band 2 (5 GHz band 1304) and band 3 (6 GHz band 1306) are reserved for high-bandwidth data transmission, while band 1 (2.4 GHz band 1302) is reserved for low-bandwidth control frames, assuming that TS and BA setup for TIDs is complete in all relevant bands. Such type of frequency division can result in an overall increase in system throughput due to reduced channel access delay in high-bandwidth frequency bands, since control frames are transmitted exclusively in low-bandwidth frequency bands.

[0054] After gaining access to the channel in each band, the AP 102 initiates a multi-band transmission consisting of a downlink PPDU 1512a in Band 3 (1306) and a downlink PPDU 1512b in Band 2 (1304). To ensure that sequence numbers do not overlap across bands, the same sequence number counter is used for each STA, TID pair across multiple bands. As with the first exemplary multi-band transmission 1300, in the second exemplary multi-band transmission 1500, the receiver STA 104 maintains separate BlockAck bitmaps for each band in its network interface (NIC), but upon receiving a multi-band BlockAckReq frame 1508a in Band 1 (1302), it consolidates the separate BlockAck bitmaps into a single BlockAck bitmap 1514a. A starting sequence number (SSN) is included in the multi-band BAR frame 1508a to indicate the first SN that will be acknowledged. The SSN triggers all frames in the receive buffer 1408 (FIG. 14) whose SN is less than the SSN to be forwarded to upper layers. During this multi-band transmission, the SN1 and SN2 frames are successfully received by the STA 104, but the SN3 and SN4 frames are unsuccessful. Bits 3 and 4 are set to "0" in the aggregate BlockAck bitmap 1514a to indicate unsuccessful reception of the SN3 and SN4 frames, while bits 1 and 2 are set to "1" to indicate successful reception of the SN1 and SN2 frames.

[0055] During this time, the AP 102 continues transmitting multi-band aggregated DL PPDU frames, including PPDU 1512c transmitted in band 3 (1306) and frame PPDU 1512d transmitted in band 2 (1304). During this transmission, the transmission of frames for SN7 and SN8 in band 2 (1304) fails. A multi-band BlockAckReq frame 1508b is transmitted in band 1 (1302) requesting a multi-band BA for the frames transmitted in the two bands 1304 and 1306. The multi-band BA 1510b aggregates the BlockAck bitmaps from the two bands 1304 and 1306 into an aggregated BlockAck bitmap 1514b.

[0056] In consolidated BlockAck bitmap 1514b, bits 7 and 8 are set to "0" to indicate unsuccessful reception of the SN7 and SN8 frames, while bits 5 and 6 are set to "1" to indicate successful reception of the SN5 and SN6 frames. Note that while bits 1 and 2 are indicated as successful receptions in consolidated BlockAck bitmap 1514a, these bits are not indicated in consolidated BlockAck bitmap 1514b for brevity. Because there was a failed transmission in band 2 (1304), but not in band 3 (1306), the transmitter may choose to consolidate the failed SN3 and SN4 frames and retransmit them as PPDU 1512e in band 3 (1306), while the failed SN7 and SN8 frames are retransmitted as PPDU 1512f in band 3 (1306). Multi-band BlockAckReq frames 1508c and 1508d are transmitted in band 1 (1302) to request multi-band BAs 1510c and 1510d, respectively, carrying acknowledgments for frames carried in PPDUs 1512e and 1512f transmitted in band 3 (1306).

[0057] Instead of regular retransmissions, retransmissions may use Hybrid Automatic Repeat request (HARQ) retransmissions, which can benefit from frequency diversity by being transmitted on different bands. PPDUs 1512a and 1512b are acknowledged in multiband BlockAck frame 1510a, PPDUs 1512c and 1512d are acknowledged in multiband BlockAck frame 1510b, PPDU 1512e is acknowledged in multiband BlockAck frame 1510c, and PPDU 1512f is acknowledged in multiband BlockAck frame 1510d. Instead of retransmitting exact copies of the failed SN3, SN4, SN7, and SN8 frames, the transmitter can choose to perform HARQ retransmissions of the failed frames (either as Chase Combing or Incremental Redundancy). HARQ retransmissions can achieve additional gains through frequency diversity, since failed frames are retransmitted on a different frequency band than the original transmission.

[0058] 16 illustrates an example 1600 of a multi-band BlockAckReq frame 1610 according to an embodiment of the present invention, where the multi-band frame variant type is defined in accordance with the present embodiment. Upon completion of a multi-band transmission 530, the multi-band BlockAckReq frame 1600 is transmitted to request a multi-band BlockAck frame and includes a BAR Control field 1612 and a BAR Information field 1614.

[0059] The BAR control field 1612 includes, among other things, a BAR Type field 1620 and a TID_INFO field 1622. The TID_INFO field 1622 indicates the number of bands (TID_INFO+1) present in the BAR. Table 1630 indicates the BAR types 1632 that can be indicated in the BAR Type field 1620 and the corresponding BAR frame variants 1634, such as compressed BAR type, multi-TID BAR type, multi-STA BAR type, and GCR BAR type. According to this embodiment, a BAR type 1636 is defined for multi-band BARs. Similarly, a corresponding new BA type is defined for multi-band BAs. The format is more flexible and can be used to request BAs for specific bands, specific TIDs, and specific BA initiation sequence controls (which may be different for each band).

[0060] According to this embodiment, the BAR information field 1614 includes a Per Band Info field 1640 and a Block Ack Starting Sequence Control field 1641 for each frequency band for which an acknowledgment is requested by the multi-band BlockAckReq frame 1610. The Per Band Info field 1640 carries information specific to the frequency band. The frequency band is identified by a Band ID field 1642. The Band ID field may follow the same encoding as the Band ID field 612 of FIG. 6. The Receiver Address (RA) and Transmitter Address (TA) fields 1644 are optionally present if different MAC addresses are used for different bands, allowing RA and TA to be identified per band. The TID Value field 1646 identifies the TID for which a Block Ack is requested in the band. The RA and TA fields 1644 may be omitted in the Per Band Info field 1640 for bands in which the BAR is transmitted.

[0061] FIG. 17 illustrates an example 1700 of a multi-band BlockAck frame 1702, in which a variant of the BA information field 1710 is defined in accordance with this embodiment. The multi-band BlockAck frame 1702 is transmitted in response to the multi-band BlockAckReq frame 1600 and includes a BA Control field 1704 and a BA information field 1710. The multi-band BlockAck frame 1702 is identified by a BA Type field 1706 set to "Multi-Band" 1636 and may be used to return a Block Ack for a specific band, a specific TID, and a specific BA initiation sequence control, which may be different for each band. The BA information field 1710 includes a per-band information field 1640 for each frequency band, as well as a per-frequency-band Block Ack initiation sequence control field 1641 and a Block Ack bitmap 1720, which are identified by the Band ID field 1730. The receiver address (RA) and transmitter address (TA) fields 1644 are optionally present if different MAC addresses are used for different bands, allowing for per-band RA and TA identification. The TID value field 1646 identifies the TID for which the Block Ack is reported in the band. The RA and TA fields 1644 may be omitted in the per-band information field 1640 for bands in which BARs are transmitted. The per-band Block Ack bitmap 1720 acknowledges only frames received in the band identified by the Band ID field 1730 in the per-band information field 1640. Thus, if frames received in three frequency bands are acknowledged, the multi-band Block Ack frame 1702 carries three Block Ack bitmap fields 1720, one for each frequency band. Upon receiving the multi-band Block Ack frame 1702, the transmitter can combine these band-specific bitmaps into a single bitmap.

[0062] Figure 18 illustrates an example 1800 of a variation of the exemplary reference model for the multi-band Block Ack implementation of Figure 14, according to this embodiment. According to the multi-band Block Ack implementation illustrated in example 1800, a separate multi-band BA scorecard 1406 need not be maintained in the host system 1805. Receipt of a multi-band BAR frame in any band triggers the generation (1810) and transmission (1820) of a multi-band BA, and the bitmap of the requested band is copied from the in-band BA scoreboard of the corresponding radio I / F and used to generate (1830) and transmit (1832) a Block Ack for the requested band. At the same time, receipt of the multi-band BAR frame 1610 triggers the upper MAC to reassemble complete MSDUs from the frames in the receive buffer 1408 (all complete MSDUs with SNs smaller than the starting sequence number (SSN)) and forward those complete MSDUs in order to the upper layer. In FIG. 18, the reception of multi-band BAR frames 1610 and the transmission of multi-band BA frames 1820 are shown in the 2.4 GHz band, although it will be understood that the process is the same for other frequency bands.

[0063] Because the multi-band BA is generated 1810 without an integrated bitmap, transmission 1820 of the multi-band BA may require longer time and therefore require a delayed Block Ack scheme. FIG. 19 shows an example 1900 of a delayed multi-band Block Ack scheme as a third exemplary multi-band transmission according to this embodiment. In the delayed multi-band Block Ack scheme, Ack frames 1902a and 1902c are transmitted in response to the multi-band Block Ack request frames 1308a and 1308b. The multi-band Block Ack frames may not be transmitted immediately after receiving the multi-band Block Ack request frames 1308a and 1308b, but may be transmitted as delayed Block Ack frames 1904a and 1904b (followed by Ack frames 1902b and 1902d) to allow the receiver time to copy the band-specific BA bitmaps from the radio I / F of each band. Thus, the multi-band Block Ack frames 1904a, 1904b carry Block Ack Information 1906a, 1906b that includes bitmaps specific to each band, and these bitmaps are not aggregated.

[0064] 20 illustrates an example 2000 of the traffic stream and Block Ack architecture objectives defined for handling multi-band transmissions and multi-band Block Acks, according to an embodiment of the present invention. Multi-band traffic streams and multi-band Block Ack agreements for TIDs are set up between the respective unified MAC addresses of the unified upper MAC layers 2002, 2012 of each device, and are band-independent and therefore much easier to manage. Multi-band traffic streams and multi-band Block Ack agreements are identified by the unified MAC address rather than by band-specific MAC addresses (i.e., multi-band transmissions are addressed to the unified MAC address regardless of the band used).

[0065] At the transmitter 302, the unified UMAC layer 2002 passes traffic streams (TSs) to a Multi-band Adaptation sublayer 2004. The Multi-band Adaptation sublayer performs multi-band aggregation of TS data across the three TS data paths 1240, 1242, and 1244 and makes decisions about which band(s) to use for transmission and retransmission. The Multi-band Adaptation sublayer 2014 at the receiver 304 is responsible for multi-band de-aggregation (i.e., reordering of frames belonging to TSs received on the three TS data paths 1240, 1242, and 1244) before passing the TSs to the receiver's unified upper MAC layer 2012.

[0066] 21 shows an example 2100 of a multiband BlockAckReq frame 2110 and a multiband BlockAck frame 2120 according to a second variation of this embodiment. The RA field 2112 and the TA field 2114 of the multiband BlockAckReq frame 2110 carry the unified MAC address of the unified upper MAC layer 2002 regardless of the band used to transmit the multiband BlockAckReq frame 2110. Similarly, the RA field 2122 and the TA field 2124 of the multiband BlockAck frame 2120 carry the unified MAC address of the unified upper MAC layer 2002 regardless of the band used to transmit the multiband BlockAck frame 2120.

[0067] The multi-band BlockAckReq frame 2110 indicates the requested band 2135 in the Band Info field 2130 of the BlockAck Request Control field 2116. Similarly, the multi-band BlockAck frame 2120 indicates the acknowledged band 2145 in the Band Info field 2140 of the Block Ack Control field 2126.

[0068] Additionally, if the Band Information field 2116 is not present in the multiband BlockAckReq frame 2110, or if all three bands are indicated by the Band Information field 2116 in the multiband BlockAckReq frame 2110, then the Block Ack Information field 2128 contains a consolidated BlockAck bitmap across the requested bands. Otherwise, the Block Ack Information field 2128 contains a BlockAck bitmap for a particular single band when that band is indicated in the Band Information field 2116.

[0069] Figure 22 illustrates an example 2200 of a second variation of the exemplary reference model for the multi-band Block Ack implementation of Figure 14, according to an embodiment of the present invention. If advances in semiconductor technology allow multiple wireless I / Fs 2210, 2220, and 2230 to be implemented as a single system on chip (SOC), or if the connection between the wireless I / Fs 2210, 2220, and 2230 and the host system 1405 is sufficiently fast, a single unified multi-band BA scoreboard 1406 may be maintained per TID, and in-band BA scorecards 1412, 1422, and 1432 (Figure 4) may not be maintained. Also, to support reporting of band-specific Block Acks (e.g., upon receipt of a legacy (single-band) BlockAckReq frame or a multi-band BlockAckReq frame 2110 (FIG. 21) having a band information field 2130 indicating one band or two bands), separate band-specific scoreboards may be maintained in cache memory at the host system 1405. Thus, receipt of a frame on any band is recorded directly in the MB BA scorecard 1406. This second variation of the exemplary reference model for multi-band Block Ack implementation may help reduce on-chip memory requirements for the multi-band Block Ack scheme.

[0070] 23 illustrates an example 2300 of an implicit multi-band Block Ack request scheme as a fourth exemplary multi-band transmission according to this embodiment. In a multi-band transmission, the PHY header of the PPDU in each band (e.g., in one of the SIG fields) carries a multi-band PPDU indication 2305 indicating that this PPDU is part of a multi-band PPDU.

[0071] For implicit and explicit Multi-band Block Ack requests, the Ack Policy bits (e.g., bits 5 and 6) in the QoS Control field (i.e., the Frame Control field of the MAC header) may be overloaded with values ​​'00' and '11', which are redefined for frames carried in multi-band PPDUs. As shown in Table 1, '00' indicates an implicit Multi-band Block Ack request (i.e., there is no Block Ack request frame and the receiver is expected to send a Multi-band Block Ack immediately), and '3' (i.e., '11') indicates an explicit Multi-band Block Ack request (i.e., an explicit or implicit Multi-band Block Ack request is expected in the same band or any other band in the future). [Table 1]

[0072] For example, multiband PPDU indication 2305 is set in DL PPDUs 2310a, 2310b, and 2310c to indicate that the three PPDUs are part of a multiband DL transmission. Bits 5 and 6 of the QoS Control fields of PPDUs 2310a and 2310b are set to "1" and "1" to indicate an explicit Multiband Block Ack request, in which case the receiver can expect a Multiband BlockAckReq frame or an Implicit Block Ack request in the future. Therefore, the receiver does not need to transmit Block Ack frames in bands 1306 and 1304. Bits 5 and 6 of the QoS Control field of PPDU 2310c are set to "0" and "0" to indicate an implicit Multiband Block Ack request, in which case the receiver is expected to immediately transmit a Multiband Block Ack without waiting for a Block Ack Request frame. Thus, a Multiband Block Ack 1310a carrying a Multiband BA Bitmap 1314a acknowledging frames received on all three bands is transmitted by the receiver within the Short Interframe Space (SIFS) after the end of the PPDU 2310c without waiting for a Multiband Block Ack Request frame.

[0073] FIG. 24 is a simplified block diagram 2400 of a multi-band communications device 2402 (e.g., an AP 102 or a STA 104 (FIG. 1)) according to this embodiment. The multi-band communications device 2402 can function as either a transmitter 302 or a receiver 304, or both, simultaneously. Of course, the AP 102 may have simultaneous TS and BA sessions with multiple non-AP STAs 104 (see FIG. 1), thus increasing complexity. Meanwhile, the non-AP STAs 104 have TS and BA sessions only with the AP 102.

[0074] The multi-band communications device 2402 includes multiple transceivers 2410, 2420, and 2430. Each of these transceivers, in transmitter operation, transmits signal frames in a different one of multiple frequency bands from a respective antenna 2412, 2422, and 2432, and, in receiver operation, receives signal frames in a different one of multiple frequency bands via a respective antenna 2412, 2422, and 2432. Each of the transceivers 2410, 2420, and 2430 includes an RF / analog front end 2414, 2424, and 2434 coupled at one end to a corresponding one of the antennas 2412, 2422, and 2432 and at the other end to a corresponding one of the physical layer (PHY) processing modules 2416, 2426, and 2436. Additionally, each of the PHY processing modules 2416 , 2426 , 2436 is coupled to a corresponding one of the lower MAC processing modules 2418 , 2428 , 2438 .

[0075] The data paths from the multiple transceivers 2410, 2420, and 2430 are coupled to an upper MAC circuit 2440. The upper MAC circuit 2440 (or upper MAC processing layer) includes a multiband scheduler 2442, a multiband aggregation / deaggregation block 2444, a multiband Block Ack generation block 2446, and a multiband Block Ack scoreboard block 2448. The multiband Block Ack generation block 2446 and the multiband Block Ack scoreboard block 2448 are used only when the multiband communication device 2402 operates as a receiver. When operating as a transmitter, the multiband scheduler 2442 records the status / capability of different bands at the receiver STA, sets up multiband TSs and multiband BAs, and determines the bands used for Multiband Block Ack transmissions / retransmissions and the bands used for Multiband Block Ack requests. When operating as a transmitter, the multiband aggregation / desaggregation block 2444 performs aggregation of traffic streams across one or more selected bands, and when operating as a receiver, performs deaggregation of traffic streams originating from different bands into a single stream. When operating as a receiver, the multiband aggregation / desaggregation block 2444 also updates the multiband block acknowledgment scoreboard block 2448. When operating as a receiver, the multiband block acknowledgment generation block 2446 is coupled to the multiband scheduler 2442 and the multiband block acknowledgment scoreboard block 2448 and generates multiband block acknowledgments.

[0076] 25 shows a detailed block diagram 2500 of a multi-band communication device 2502 according to this embodiment. Each of the wireless I / Fs 2510, 2520, and 2530 implements both a corresponding one of the physical layer (PHY) processing modules 2416, 2426, and 2436 and a corresponding one of the lower MAC function modules 2512, 2522, and 2532. The upper MAC function may be implemented as software in a central processing unit (CPU) 2540, which may be coupled to a memory 2542, a secondary storage device 2544, and a wired communication I / F 2546 for communicating with external networks or other APs 102 during operation, which may be used to store a multi-band BA scoreboard. A power supply 2548 provides power to the AP 2502.

[0077] The present disclosure may be implemented in any type of apparatus, device, or system having a communication capability (collectively referred to as a communication device).

[0078] A communication device may include a transceiver and processing / control circuitry. The transceiver may include and / or function as a receiver and a transmitter. The transceiver may include a radio frequency (RF) module as a transmitter and a receiver. The RF module may include an amplifier, an RF modulator / demodulator, or the like, and one or more antennas.

[0079] Non-limiting examples of communication devices include telephones (e.g., mobile phones, smartphones), tablets, personal computers (PCs) (e.g., laptops, desktops, notebooks), cameras (e.g., digital still cameras / video cameras), digital players (e.g., digital audio players / video players), wearable devices (e.g., wearable cameras, smart watches, tracking devices), game consoles, digital book readers, telehealth / telemedicine devices, communication-enabled vehicles (e.g., cars, airplanes, ships), and combinations of the above devices.

[0080] Communication devices are not limited to portable or mobile devices, but also include any kind of equipment, device, or system that is non-portable or fixed, such as smart home devices (such as home appliances, lighting equipment, smart meters, control panels, etc.), vending machines, and any other "things" that may exist on an IoT (Internet of Things) network.

[0081] Communications include data communications via cellular systems, wireless LAN systems, communications satellite systems, etc., as well as data communications via combinations of these.

[0082] A communications device also includes devices such as controllers and sensors connected or coupled to a communications apparatus that performs the communications functions described in this disclosure, such as controllers and sensors that generate control and data signals used by the communications apparatus to perform the communications functions of the communications device.

[0083] Communication devices also include infrastructure facilities, such as base stations, access points, and any other apparatus, device, or system that communicate with or control the various non-limiting devices listed above.

[0084] Thus, it can be seen that the present embodiments provide communications devices and methods for operating across multiple frequency bands to fully realize the throughput gains of multi-band aggregation.

[0085] 1. A multi-band communications device comprising: a plurality of transceivers, each of which, in operation, transmits signal frames in a different frequency band among a plurality of frequency bands; and a media access control (MAC) circuit coupled to the plurality of transceivers, which, in operation, receives a multi-band block acknowledgment frame in one frequency band among the plurality of frequency bands, acknowledging the signal frames transmitted in the plurality of frequency bands.

[0086] 2. A multi-band communications device, wherein the MAC circuit, in operation, generates a multi-band block acknowledgment request frame to request the multi-band block acknowledgment frame, and transmits the multi-band block acknowledgment request frame in the one frequency band of the plurality of frequency bands.

[0087] 3. A multi-band communication device, wherein the signal frames transmitted in the multiple frequency bands all belong to a single traffic identifier (TID).

[0088] 4. A multi-band communications device, wherein the multi-band block acknowledgement frame is implicitly requested in any one of the transmitted signal frames.

[0089] 5. A multi-band communications device, wherein in response to the MAC circuit determining that one or more signal frames have been unsuccessfully received in a first frequency band of the plurality of frequency bands, the MAC circuit provides the one or more signal frames to one transceiver unit of the plurality of transceivers that transmits the signal frames in a second frequency band of the plurality of frequency bands that is different from the first frequency band of the plurality of frequency bands, and retransmits the one or more signal frames in the second frequency band of the plurality of frequency bands.

[0090] 6. A multi-band communication device, wherein the one or more signal frames retransmitted in the second frequency band of the plurality of frequency bands are transmitted in the same format as the one or more signal frames transmitted in the first frequency band of the plurality of frequency bands.

[0091] 7. A multi-band communications device, wherein the one or more retransmitted signal frames are retransmitted as hybrid automatic repeat request (HARQ) retransmissions.

[0092] 8. A multi-band communications device, wherein the MAC circuit, in operation, performs setup of a multi-band traffic stream (TS) in the multiple frequency bands by exchanging multi-band traffic stream add (ADDTS) request frames and multi-band ADDTS response frames in one frequency band of the multiple frequency bands.

[0093] 9. A multiband communications device, wherein each of the multiband ADDTS request frame and the multiband ADDTS response frame includes information about the multiple frequency bands for the multiband TS and a MAC address used by the MAC circuit in each of the multiple frequency bands.

[0094] 10. The multiband communication device described in 8, wherein the multiband TS setup enables transmission of signal frames belonging to a traffic stream (TS) in any of the multiple frequency bands.

[0095] A multi-band communication device, wherein two or more frequency bands of the plurality of frequency bands include all of the plurality of frequency bands.

[0096] A multi-band communication device, wherein the plurality of frequency bands are all frequency bands above 2 GHz.

[0097] 11. A method for multi-band communication, comprising: transmitting signal frames in different frequency bands of a plurality of frequency bands; and receiving a multi-band block acknowledgment frame in one frequency band of the plurality of frequency bands.

[0098] 12. A multi-band communications device comprising: a plurality of transceivers, each of which, in operation, receives signal frames in a different frequency band among a plurality of frequency bands; and a media access control (MAC) circuit coupled to the plurality of transceivers, which, in operation, generates a multi-band block acknowledgment frame that acknowledges the signal frames received in the plurality of frequency bands, and transmits the multi-band block acknowledgment frame in one frequency band among the plurality of frequency bands.

[0099] 13. A multi-band communications device, wherein, in operation, the MAC circuit transmits the multi-band block acknowledgment frame in response to receiving a multi-band block acknowledgment request frame in the one frequency band of the plurality of frequency bands.

[0100] 14. A multi-band communications device, wherein the multi-band block acknowledgment frame includes a joint bitmap acknowledging signal frames received on the multiple frequency bands.

[0101] 15. A multi-band communications device, wherein the multi-band block acknowledgment frame transmitted in one frequency band of the plurality of frequency bands includes a bitmap acknowledging signal frames received in each of the plurality of frequency bands.

[0102] 16. A multiband communications device, wherein the multiband block acknowledgment frame transmitted in one frequency band of the plurality of frequency bands includes a bitmap acknowledging a signal frame received in another frequency band of the plurality of frequency bands.

[0103] 17. A multi-band communications device, wherein the MAC circuit, in operation, initiates a multi-band block acknowledgement (BA) setup in the multiple frequency bands by transmitting a multi-band block acknowledgement add (ADDBA) request frame in one frequency band of the multiple frequency bands and subsequently receiving a multi-band ADDBA response frame in the one frequency band of the multiple frequency bands.

[0104] 18. A multi-band communications device, wherein each of the multi-band ADDBA request frame and the multi-band ADDBA response frame includes information regarding the multiple frequency bands for the multi-band BA agreement and a MAC address used by the MAC circuit in each of the multiple frequency bands.

[0105] A multi-band communication device, wherein two or more frequency bands of the plurality of frequency bands include all of the plurality of frequency bands.

[0106] A multi-band communication device, wherein the plurality of frequency bands are all frequency bands above 2 GHz.

[0107] 19. A method for multi-band communication, comprising: receiving signal frames in different frequency bands of a plurality of frequency bands; and transmitting, in one frequency band of the plurality of frequency bands, a multi-band block acknowledgment frame that acknowledges the signal frames received in the plurality of frequency bands.

[0108] While exemplary embodiments have been presented in the foregoing detailed description of the present embodiments, it should be understood that numerous variations exist. It should be further understood that the exemplary embodiments are examples and are not intended to limit in any way the scope, applicability, operation, or configuration of the present disclosure. Rather, the foregoing detailed description provides those skilled in the art with a convenient road map for implementing the exemplary embodiments, and it should be understood that various changes may be made in the function and arrangement of the steps and methods of operation described in the exemplary embodiments, and in the modules and structure of the devices described in the exemplary embodiments, without departing from the scope of the subject matter set forth in the appended claims.

Claims

1. a control unit that forms a multi-band block confirmation agreement with a multi-band transmitting device on a single frequency band for a single traffic identifier (TID) across multiple frequency bands; a receiver configured to receive a plurality of MAC layer protocol data units (MPDUs) belonging to the single TID transmitted in the plurality of frequency bands from the multi-band transmitting device; a transmitter configured to transmit, on a first frequency band different from the frequency band, a multiband block acknowledgment frame indicating a reception status of each of the plurality of MPDUs, the plurality of MPDUs including one or more MPDUs transmitted in the frequency band; Equipped with the transmitting unit transmits, in one frequency band, a block acknowledgement frame for each band indicating a reception status of only MPDUs transmitted in one frequency band among the plurality of frequency bands among the plurality of MPDUs belonging to the single TID; Multi-band receiving device.

2. exchanging add traffic stream (ADDTS) request frames and add traffic stream (ADDTS) response frames with the multi-band receiving device to form a single multi-band block confirmation agreement for the TID; 10. The multi-band receiving device of claim 1.

3. the receiving unit transmits, in another frequency band, a block confirmation for each band indicating a reception status of some of the MPDUs transmitted in a certain frequency band among the plurality of MPDUs; 10. The multi-band receiving device of claim 1.

4. The plurality of MPDUs may be transmitted in any of the plurality of frequency bands.

10. The multi-band receiving device of claim 1.

5. after transmitting a multiband block acknowledgment frame indicating that reception of a first MPDU transmitted in a first frequency band among the plurality of frequency bands has failed, the receiving unit receives the first MPDU retransmitted in a second frequency band among the plurality of frequency bands that is different from the first frequency band among the plurality of frequency bands; 10. The multi-band receiving device of claim 1.

6. The receiver receives a multiband block acknowledgement request frame including one or more per-band information fields, each of the one or more per-band information fields including a TID value field indicating the TID for which a block acknowledgement is requested in the corresponding frequency band. A multi-band receiving device according to claim 5.

7. 1. A communication method for a multi-band receiving device, comprising: forming a multi-band block confirmation agreement on a single frequency band with a multi-band transmitting device for a single traffic identifier (TID) across multiple frequency bands; receiving a plurality of MAC layer protocol data units (MPDUs) belonging to the single TID transmitted in the plurality of frequency bands from the multi-band transmitting device; transmitting, on a first frequency band different from the frequency band, a multiband block acknowledgment frame indicating a reception status of each of the plurality of MPDUs, the plurality of MPDUs including one or more MPDUs transmitted in the frequency band; transmitting, in one frequency band, a block acknowledgement frame for each band indicating a reception status of only MPDUs transmitted in one frequency band among the plurality of frequency bands among the plurality of MPDUs belonging to the single TID; Communication method.

8. exchanging add traffic stream (ADDTS) request frames and add traffic stream (ADDTS) response frames with the multi-band receiving device to form a single multi-band block confirmation agreement for the TID; The communication method according to claim 7.

9. transmitting, in another frequency band, a block confirmation for each band indicating a reception status of a portion of the MPDUs transmitted in a certain frequency band among the plurality of MPDUs; The communication method according to claim 7.

10. The plurality of MPDUs may be transmitted in any of the plurality of frequency bands. The communication method according to claim 7.

11. transmitting a multiband block acknowledgment frame indicating that reception of a first MPDU transmitted in a first frequency band among the plurality of frequency bands has failed, and then receiving the first MPDU retransmitted in a second frequency band among the plurality of frequency bands that is different from the first frequency band among the plurality of frequency bands; The communication method according to claim 7.

12. receiving a multi-band block acknowledgement request frame including one or more per-band information fields, each of the one or more per-band information fields including a TID value field indicating the TID for which a block acknowledgement is requested in that frequency band; The communication method according to claim 11.

13. 1. An integrated circuit for a multi-band receiving device, comprising: forming a multi-band block confirmation agreement on a single frequency band with a multi-band transmitting device for a single traffic identifier (TID) across multiple frequency bands; receiving a plurality of MAC layer protocol data units (MPDUs) belonging to the single TID transmitted in the plurality of frequency bands from the multi-band transmitting device; transmitting, on a first frequency band different from the frequency band, a multiband block acknowledgment frame indicating a reception status of each of the plurality of MPDUs, the plurality of MPDUs including one or more MPDUs transmitted in the frequency band; transmitting, in one frequency band, a block acknowledgement frame for each band indicating a reception status of only MPDUs transmitted in one frequency band among the plurality of frequency bands among the plurality of MPDUs belonging to the single TID; An integrated circuit that controls

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