Mobile terminal decode failure procedure in a wireless local area network
First Claim
1. A method for implementing a mobile terminal decode failure procedure in a wireless local area network, comprising the steps of:
- sending a sleep request from a mobile terminal in the network to an access point in the network, wherein the sleep request includes a proposed sleep interval;
receiving a sleep reservation in the mobile terminal from the access point, wherein the sleep reservation includes a sleep duration and a sleep start time for the mobile terminal;
the mobile terminal going to sleep at the sleep start time;
the mobile terminal listening, at the end of the sleep duration, for a wakeup announcement in a Medium Access Control (MAC) frame sent by an access point in the network;
determining in the mobile terminal, whether the mobile terminal has failed to properly decode a wakeup announcement in a Medium Access Control (MAC) frame sent by the access point in the network; and
in the mobile terminal, in response to a determined decode failure, remaining awake to monitor subsequent MAC frames until either a predetermined number of MAC frames transpire, or a wakeup announcement intended to awaken the mobile terminal is properly decoded, whichever occurs first.
1 Assignment
0 Petitions
Accused Products
Abstract
In accordance with embodiments of the invention, in a Wireless Local Area Network (WLAN) configured in accordance with the HIPERLAN Type 2 standard where an Access Point (AP) and Mobile Terminals (MTs) use a duplex airlink having a MAC frame structure to communicate with each other, when an MT fails to properly perceive and decode a wakeup announcement in the MAC frame that is directed to it by the AP, the MT will remain awake and continue to decode and monitor subsequent MAC frames until it either receives a wakeup announcement directed to it, or until a predetermined number of MAC frames transpire. Where the MT fails to correctly decode a wakeup announcement and/or fails to send an acknowledgment signal back to the AP when the wakeup announcement includes a polling request, the AP will continue to resend the wakeup announcement and any appropriate, associated downlink data pending for the AP, in subsequent MAC frames. The AP continues until either the MT correctly receives the wakeup announcement and responds appropriately, or until a predetermined number of MAC frames expire.
102 Citations
9 Claims
-
1. A method for implementing a mobile terminal decode failure procedure in a wireless local area network, comprising the steps of:
-
sending a sleep request from a mobile terminal in the network to an access point in the network, wherein the sleep request includes a proposed sleep interval;
receiving a sleep reservation in the mobile terminal from the access point, wherein the sleep reservation includes a sleep duration and a sleep start time for the mobile terminal;
the mobile terminal going to sleep at the sleep start time;
the mobile terminal listening, at the end of the sleep duration, for a wakeup announcement in a Medium Access Control (MAC) frame sent by an access point in the network;
determining in the mobile terminal, whether the mobile terminal has failed to properly decode a wakeup announcement in a Medium Access Control (MAC) frame sent by the access point in the network; and
in the mobile terminal, in response to a determined decode failure, remaining awake to monitor subsequent MAC frames until either a predetermined number of MAC frames transpire, or a wakeup announcement intended to awaken the mobile terminal is properly decoded, whichever occurs first. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
determining in an access point in the network, whether a mobile terminal in the network has failed to properly decode a wakeup announcement in a Medium Access Control (MAC) frame sent by an access point in the network; and
retransmitting the wakeup announcement in subsequent MAC frames from the access point to the mobile terminal, prior to a next scheduled wakeup announcement broadcast period for the mobile terminal, until either a number of retransmissions reaches a predetermined threshold, or the mobile terminal successfully decodes one of the retransmitted wakeup announcements, whichever occurs first.
-
-
3. The method of claim 2, wherein when the wakeup announcement includes a polling request and the mobile terminal fails to respond to the polling request, determining that the mobile terminal has failed to properly decode the wakeup announcement.
-
4. The method of claim 1, wherein when the access point includes a null pointer in the wakeup announcement, the mobile terminal remains awake and decodes each Broadcast Control Channel (BCCH) and Frame Control Channel (FCCH) that comes along, until further notice.
-
5. The method of claim 4, wherein the access point minimizes bandwidth use by including the null pointer in the wakeup announcement.
-
6. The method of claim 4, wherein the access point sends at least two wakeup announcements to the mobile terminal, each of the at least two wakeup announcements including the null pointer.
-
7. The method of claim 1, wherein the predetermined number of MAC frames is greater than 1.
-
8. The method of claim 4, wherein the null indicator indicates that a) the MAC frame does not contain downlink data for the mobile terminal, and b) the mobile terminal should remain awake to await downlink data that will be provided in the future.
-
9. The method of claim 8, wherein the null indicator indicates that the mobile terminal should not send a reply signal to the access point.
Specification