Restricted target wake time service period termination
A wireless communication protocol using CSMA/CA, EDCA and R-TWT to prioritize RTA traffic transmissions. During an R-TWT SP, the RTA traffic is prioritized for transmission and mechanisms are provided for assuring proper indications and termination of the R-TWT SP. During this process, member STAs communicate with the R-TWT scheduling AP when they have no more frames to send. The R-TWT scheduling AP can also terminate the R-TWT SP before its scheduled end time, allowing non-member STAs to immediately contend for the channel. In addition, the R-TWT scheduling AP can exchange frames with STAs, that have an R-TWT feature but are not R-TWT member STAs, after frame exchanges with the R-TWT member STAs during the R-TWT SP have been completed.
1 . An apparatus for wireless communication in a network, the apparatus comprising:
(a) a wireless communication circuit, as a station (STA) which is separate or associated with a multi-link device (MLD), wherein said station is configured for wirelessly communicating over a channel with other wireless stations (STAs) performing transmissions of frames with their packets using carrier sense multiple access/collision avoidance (CSMA/CA) on a wireless local area network (WLAN) under an IEEE 802 protocol for a scheduling service period (SP) for a restricted target wake time (R-TWT);
(b) a processor coupled to said STA for operating on the WLAN;
(c) a non-transitory memory storing instructions executable by the processor for communicating with other STAs in a communications protocol; and
(d) wherein said instructions, when executed by the processor, perform one or more steps in announcing R-TWT scheduling to exchange frames with R-TWT member STAs comprising:
(i) wherein said station, operating as an access point (AP) which is configured for performing R-TWT scheduling, as an R-TWT scheduling AP, announces R-TWT scheduling, including a scheduled end time of an R-TWT SP, and exchanges frames with a R-TWT member STA, of the R-TWT member STAs, after entering into an R-TWT SP;
(ii) wherein said R-TWT scheduling AP enters into negotiation with one or more of the R-TWT member STAs in determining which traffic streams are to be transmitted with higher priority during the announced R-TWT SP, with scheduled traffic prioritized to transmit during the R-TWT SP;
(iii) wherein said R-TWT scheduling AP receives signals from one or more of the R-TWT member STAs indicating that there are no more frames of scheduled traffic to be transmitted; and
(iv) wherein said R-TWT scheduling AP, after all the frame exchanges have been completed during the R-TWT SP, can share any of the remaining time of the R-TWT SP before it transmits a signal to indicate termination of the R-TWT SP, in a termination announcement.
2 . The apparatus of claim 1 , wherein termination announcement from said R-TWT scheduling AP occurs before the scheduled end time of the R-TWT SP.
3 . The apparatus of claim 1 , further comprising exchanging frames between said R-TWT scheduling AP and the R-TWT member STAs during said R-TWT SP.
4 . The apparatus of claim 3 , further comprising exchanging frames between said R-TWT scheduling AP with STAs that have an R-TWT feature but are not R-TWT member STAs, after said R-TWT scheduling AP completes frame exchanges with the R-TWT member STAs during the R-TWT SP.
5 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising the R-TWT member STA sending a signal to said R-TWT scheduling AP when it does not have any uplink (UL) or peer-to-peer (P2P) frames to transmit during the R-TWT SP.
6 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising said R-TWT member STA sending a frame indicating that it does not have frames to transmit during the R-TWT SP.
7 . The apparatus of claim 6 , wherein said frame which indicates that it does not have frames to transmit during the R-TWT SP comprises (a) a frame that is neither a quality-of-service (QOS) data frame or a QoS Null frame; and (b) a frame which contains a field indicating whether it has more data, as a more data field which is in a state representing that said R-TWT member STA does not have any more frames to transmit during the R-TWT SP.
8 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising the R-TWT member STA sending a QoS data or QoS Null frame with the end of service period (EOSP) subfield set to a state which indicates that the R-TWT member STA does not have UL and/or P2P frames to transmit during the R-TWT SP.
9 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising said R-TWT scheduling AP sending a QoS data frame, or QoS Null frame, with an end of service period (EOSP) subfield set to a state which indicates termination of the R-TWT SP.
10 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising said R-TWT scheduling AP sending a frame, that is neither a QoS data frame or a QoS Null frame, with the frame having a field, as a more data field, for indicating when there is more data to be sent, and said more data field is set to a value indicating the termination of the R-TWT SP.
11 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising said R-TWT scheduling AP sending a contention-free (CF) end frame to indicate termination of the R-TWT SP.
12 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising said R-TWT scheduling AP sending a trigger frame, not addressed to any specific R-TWT member STAs, having a field for indicating when there are more trigger frames, and setting that field to indicate the termination of the R-TWT SP.
13 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising said R-TWT scheduling AP sending a TWT information frame that has a TWT flow identification field set equal to the R-TWT identification, to indicate the termination of the R-TWT SP.
14 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising the R-TWT member STA recognizing that the R-TWT SP has terminated, in response to receiving a frame from said R-TWT scheduling AP containing an indication that the R-TWT SP has terminated.
15 . The apparatus of claim 1 , wherein said instructions when executed by the processor further perform steps comprising the R-TWT member STA recognizing that the R-TWT SP has terminated in response to receiving an acknowledgement, from said R-TWT scheduling AP, indicating that the R-TWT SP has terminated.
16 . An apparatus for wireless communication in a network, the apparatus comprising:
(a) a wireless communication circuit, as a station (STA) which is separate or associated with a multi-link device (MLD), wherein said station is configured for wirelessly communicating over a channel with other wireless stations (STAs) performing transmissions of frames with their packets using carrier sense multiple access/collision avoidance (CSMA/CA) on a wireless local area network (WLAN) under an IEEE 802 protocol for a scheduling service period (SP) for a restricted target wake time (R-TWT);
(b) a processor coupled to said STA for operating on the WLAN;
(c) a non-transitory memory storing instructions executable by the processor for communicating with other STAs; and
(d) wherein said instructions, when executed by the processor, perform one or more steps in announcing R-TWT scheduling to exchange frames with member STAs of the R-TWT comprising:
(i) wherein said station, operating as an access point (AP) which is configured for performing R-TWT scheduling, as an R-TWT scheduling AP; and wherein said R-TWT scheduling AP and the R-TWT member STAs enter into an R-TWT SP;
(ii) terminating said R-TWT SP, by said R-TWT scheduling AP, before the scheduled end time of the R-TWT SP and sending a termination announcement on the channel; (iii)
(iii) wherein other STAs on the network, which are not member STAs of the R-TWT, in response to receiving said termination announcement, can immediately contend for the channel; and
(iv) wherein said R-TWT member STA is not allowed to contend for the channel after the R-TWT SP terminates, until the scheduled end time of the R-TWT SP is arrived at.
17 . The apparatus of claim 16 , wherein said instructions when executed by the processor further perform steps comprising said R-TWT scheduling AP sending a signal over the channel to indicate the termination of the R-TWT SP.
18 . The apparatus of claim 16 , wherein said instructions when executed by the processor further perform steps comprising allowing the R-TWT member STAs to contend for the channel with lower priority than regular EDCA parameter settings for those R-TWT member STAs, after the R-TWT SP terminates until the scheduled end time of the R-TWT SP.
19 . An apparatus for wireless communication in a network, the apparatus comprising:
(a) a wireless communication circuit, as a station (STA) which is separate or associated with a multi-link device (MLD), wherein said station is configured for wirelessly communicating over a channel with other wireless stations (STAs) performing transmissions of frames with their packets using carrier sense multiple access/collision avoidance (CSMA/CA) on a wireless local area network (WLAN) under an IEEE 802 protocol for a scheduling service period (SP) for a restricted target wake time (R-TWT);
(b) a processor coupled to said STA for operating on the WLAN;
(c) a non-transitory memory storing instructions executable by the processor for communicating with other STAs; and
(d) wherein said instructions, when executed by the processor, perform one or more steps in announcing R-TWT scheduling to exchange frames with member STAs of the R-TWT comprising:
(i) wherein said station, operating as an access point (AP) which is configured for performing R-TWT scheduling, as an R-TWT scheduling AP; and wherein said R-TWT scheduling AP and the R-TWT member STAs enter into an R-TWT SP;
(ii) terminating said R-TWT SP, by said R-TWT scheduling AP, before the scheduled end time of the R-TWT SP and sending a termination announcement on the channel;
(iii) wherein other STAs on the network, which are not member STAs of the R-TWT, in response to receiving said termination announcement, can immediately contend for the channel; and
(iv) wherein said instructions when executed by the processor further perform steps comprising allowing the R-TWT member STAs to contend for the channel with lower priority than regular EDCA parameter settings for those R-TWT member STAs, after the R-TWT SP terminates until the scheduled end time of the R-TWT SP.
20 . The apparatus of claim 19 , wherein said instructions when executed by the processor further perform steps comprising said R-TWT scheduling AP sending a signal over the channel to indicate the termination of the R-TWT SP.
21 . The apparatus of claim 19 , wherein said R-TWT member STA is not allowed to contend for the channel after the R-TWT SP terminates, until the scheduled end time of the R-TWT SP is arrived at.