Patent application number | Description | Published |
20080267162 | Method and Apparatus Performing Express Forwarding Bypass for Time-Critical Frames - A method, apparatus and computer program product for the express forwarding bypass are presented. A timer (NAV) is maintained at each respective node of a wireless LAN, the timer (NAV) set to a corresponding time period during which the respective node must refrain from transmitting on a channel. The first node of said plurality of nodes has a time-critical (TC) frame. The first node detects a frame to be express-forwarded by a second node. The first node decrements the duration field by a first predetermined time increment (DT | 10-30-2008 |
20080291873 | HYBRID COORDINATION FUNCTION (HCF) ACCESS THROUGH TIERED CONTENTION AND OVERLAPPED WIRELESS CELL MITIGATION - A method and system reduce interference between overlapping first and second wireless LAN cells in a medium. Each cell includes a respective plurality of member stations and there is at least one overlapped station occupying both cells. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point transmits a beacon packet containing the inter-cell contention-free period value, which is intercepted at the overlapped station. The overlapped station forwards the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires. The beacon packet sent by the first access point station also includes an intra-cell contention-free period value, which causes the member stations in the first cell to delay accessing the medium until polled by the first access point. After the expiration of the intra-cell contention-free period, member stations in the first cell may contend for the medium based on the quality of service (QoS) data they are to transmit, using the Tiered Contention Multiple Access (TCMA) protocol. | 11-27-2008 |
20090232155 | METHOD AND APPARATUS FOR COORDINATING ADJACENT CHANNEL TRANSMISSIONS ON MULTIPLE RADIO NODES - A method, apparatus and computer program product for coordinating adjacent channel transmissions on multiple-radio nodes is presented. A Maximum Channel Occupancy Duration (MCOD) limit for a length of an overall transmit period is defined. A set of timers (NNAV) for each neighbor node is maintained, each of said NNAV including a first timer (CTSNNAV) for the channel which, if set, indicates the maximum duration of a transmission to said neighbor node and a second timer (RTSNNAV) for a channel which, if set, prevents the neighbor node from authorizing a transmission the channel. | 09-17-2009 |
20090252135 | EFFICIENT POWER MANAGEMENT IN WIRELESS LOCAL AREA NETWORKS - A method of providing power management in a Wireless Local Area Network (WLAN) is presented. The method includes receiving a Traffic Indication Map (TIM) at a station, indicating the presence of buffered frames, associated with any AC, for the station at an Access Point (AP). The method further includes sending, by the station, one of an uplink data frame if one is buffered, and a null frame to retrieve the buffered frames from said AP. The station remains awake to receive frames from the AP until a downlink frame is received containing an indication that it is the last frame to be transmitted in the service period. The method may further include determining at the end of service period whether there are more frames remaining buffered for the station at the AP. | 10-08-2009 |
20090323650 | METHOD AND APPARATUS PERFORMING EXPRESS FORWARDING FRAMES HAVING MULTIPLE FRAGMENTS - A method, apparatus and computer program product for the express forwarding frames having multiple fragments are presented. A timer (NAV) is maintained at each respective node of a wireless Local Area Network (LAN). At least two fragments of a frame are designated as a Time Sensitive Quality of Service (TSQ) frame fragments to be express forwarded. A duration field of each of the TSQ frame fragments is incremented by a first predetermined time increment (DT | 12-31-2009 |
20100069080 | Call Admission Control for Mobility-Capable Telecommunications Terminals - A method and apparatus are disclosed that enable taking into consideration the variation in channel occupancy of a particular terminal or terminals during the call admission process. A channel utilization manager accounts for the probabilistic nature of the call admission decision by using a pre-determined, statistically justified value to represent the channel occupancy. The “per-call” channel occupancy value is determined by a number of factors, including the shared-communications channel data rate. Channel occupancy is incorporated into one or more cumulative distribution functions (CDF), which are evaluated by the channel utilization manager as part of the call admission process. In turn, each channel-occupancy CDF of a shared-communications channel can be generated from a CDF of the terminals' data rates on that channel, which data rates can be determined analytically or empirically. | 03-18-2010 |
20100131815 | METHOD AND APPARATUS PERFORMING EXPRESS RETRANSMISSION OF FRAMES - A method, apparatus and computer program product for the express forwarding are presented. A node attempts to transmit a frame designated as a Time Sensitive Quality of Service (TSQ) frame to be express forwarded from a first node to a second node of a plurality of nodes. A collision is detected involving the TSQ frame while attempting to transmit the TSQ frame. A retransmission of the TSQ frame is attempted without waiting a predetermined back off period. | 05-27-2010 |
20100254365 | EMERGENCY CALL HANDLING IN CONTENTION-BASED WIRELESS LOCAL AREA NETWORKS - An apparatus and methods for handling emergency message frames (e.g., “911” call frames, etc.) sent by a station in a wireless local-area network are disclosed. The illustrative embodiment increases the probability with which an emergency message frame is accorded the singularly highest quality-of-service by modifying one or more IEEE 802.11 e parameters (e.g., back-off contention window length, Arbitration Inter-Frame Space [AIFS], etc.) for a station or access point that transmits an emergency message frame. | 10-07-2010 |
20110188484 | METHOD AND APPARATUS FOR IMPLEMENTING A BLANKET WIRELESS LOCAL AREA NETWORK CONTROL PLANE - A method and apparatus for maintaining a connection between a wireless transmit/receive unit (WTRU) and a blanket wireless local area network (BWLAN) are described. An inter-working function (IWF) entity in a given network access point (NAP) of the BWLAN maintains lists of WTRUs in respective states. Furthermore, the given NAP maintains a list of neighbor NAPs, and operates in accordance with a selected WTRU mobility protocol. The states may include a “not aware” (NA) state in which the given NAP is actually not aware of a particular WTRU, an “active transmit” (AT) state in which the given NAP is actively transmitting to a particular WTRU, and a “neighbor range” (NR) state for WTRUs indicated in an update report from neighbor (URN) message that the given NAP was not aware of. The WTRU mobility protocol may be a push mobility protocol or a poll mobility protocol. | 08-04-2011 |
20110211476 | METHOD FOR UPLINK SPECTRUM MONITORING FOR SPARSE OVERLAY TDMA SYSTEMS - Spectrum monitoring measurements are made by microcell base stations in a layered cellular network, while not serving calls or engaged in processing calls. The microcell base station transmits a first control message from to a microcell mobile station, to increase the duration for the mobile station to reside in the camping state on a control channel of the microcell base station. The microcell base station transmits a second control message from the microcell base station to the microcell mobile station, to increase the duration for the mobile station to reside in a call origination state while attempting to access a control channel of the microcell base station. Then, to perform the spectrum monitoring measurement, the base station's transmitter is turned off, the receiver is retuned to the frequency to be monitored, a signal strength measurement taken on that frequency, the receiver is retuned back to its assigned frequency, and the transmitter is turned back on, all in a short time interval. Because the measurement time is so short, it is possible to take spectrum-monitoring measurements without causing inactive mobiles registered on the measuring base station to reselect control channel. Mobiles initiating a call during a spectrum monitoring measurement by its base station are also delayed in their control channel reselection. | 09-01-2011 |
20120069832 | PREEMPTIVE PACKET FOR MAINTAINING CONTIGUITY IN CYCLIC PRIORITIZED MULTIPLE ACCESS (CPMA) CONTENTION-FREE SESSIONS - An access point transmits a preemptive peg packet when it has no data to transmit in order to maintain the contiguity of its transmission timing position with respect to the timing position of other contention-free sessions (CFS) transmitted by other access points in an existing, periodic sequence. The cyclic prioritized multiple access (CDMA) method establishes the transmission timing position of contention-free sessions (CFS) between overlapping first and second wireless LAN cells contending for the same medium. Each cell includes a respective plurality of member stations. If an access point has no traffic, it will transmit a short, preemptive pegging packet and reset its backoff timer. In this manner, no gaps longer than the distributed coordination function (DCF) Interframe Space (DIFS) are left idle. This prevents other stations from using DCF contention to seize the channel, until all access points have completed one contention-free session (CFS) per periodic cycle. | 03-22-2012 |
20120127965 | HYBRID COORDINATION FUNCTION (HCF) ACCESS THROUGH TIERED CONTENTION AND OVERLAPPED WIRELESS CELL MITIGATION - A method and system reduce interference between overlapping first and second wireless LAN cells in a medium. Each cell includes a respective plurality of member stations and there is at least one overlapped station occupying both cells. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point transmits a beacon packet containing the inter-cell contention-free period value, which is intercepted at the overlapped station. The overlapped station forwards the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires. | 05-24-2012 |
20120213166 | HYBRID COORDINATION FUNCTION (HCF) ACCESS THROUGH TIERED CONTENTION AND OVERLAPPED WIRELESS CELL MITIGATION - A method and system reduce interference between overlapping first and second wireless LAN cells in a medium. Each cell includes a respective plurality of member stations and there is at least one overlapped station occupying both cells. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point transmits a beacon packet containing the inter-cell contention-free period value, which is intercepted at the overlapped station. The overlapped station forwards the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires. | 08-23-2012 |
20120230262 | 'SHIELD': PROTECTING HIGH PRIORITY CHANNEL ACCESS ATTEMPTS IN OVERLAPPED WIRELESS CELLS - A method and system reduce interference between overlapping first and second wireless LAN cells contending for the same medium. Each cell includes a respective plurality of member stations. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point in the first cell transmits an initial shield packet to deter other stations from contending for the medium. The access point then transmits a beacon packet containing the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires. | 09-13-2012 |
20120327919 | FIXED DETERMINISTIC POST-BACKOFF FOR CYCLIC PRIORITIZED MULTIPLE ACCESS (CPMA) CONTENTION-FREE SESSIONS - A cyclic prioritized multiple access method is disclosed which includes Fixed Deterministic Post-Backoff. Fixed deterministic post-backoff reduces conflicts between access points of overlapping cells. Contention-free sessions can be generated, one from each overlapping cell. Each active access point engages in a fixed deterministic post-backoff. A fixed deterministic backoff delay (Bkoff times a fixed number of idle time slots) is used by all access points, with the value of Bkoff being greater than the number of overlapping cells. The Bkoff should be large enough to enable the traffic that needs to be accommodated by the channel. Each access point has a backoff timer that is counted down using the shortest interframe space possible. A contention-free session is initiated when the backoff timer expires, and it is then reset to the value of Bkoff to start a new cycle. | 12-27-2012 |
20140010081 | TIERED CONTENTION MULTIPLE ACCESS (TCMA): A METHOD FOR PRIORITY-BASED SHARED CHANNEL ACCESS - Quality of Service (QoS) support is provided by means of a Tiered Contention Multiple Access (TCMA) distributed medium access protocol that schedules transmission of different types of traffic based on their service quality specifications. In one embodiment, a wireless station is supplied with data from a source having a lower QoS priority QoS(A), such as file transfer data. Another wireless station is supplied with data from a source having a higher QoS priority QoS(B), such as voice and video data. Each wireless station can determine the urgency class of its pending packets according to a scheduling algorithm. For example file transfer data is assigned lower urgency class and voice and video data is assigned higher urgency class. There are several urgency classes which indicate the desired ordering. Pending packets in a given urgency class are transmitted before transmitting packets of a lower urgency class. | 01-09-2014 |
20140010226 | PREEMPTIVE PACKET FOR MAINTAINING CONTIGUITY IN CYCLIC PRIORITIZED MULTIPLE ACCESS (CPMA) CONTENTION-FREE SESSIONS - An access point transmits a preemptive peg packet when it has no data to transmit in order to maintain the contiguity of its transmission timing position with respect to the timing position of other contention-free sessions (CFS) transmitted by other access points in an existing, periodic sequence. The cyclic prioritized multiple access (CPMA) method establishes the transmission timing position of contention-free sessions (CFS) between overlapping first and second wireless LAN cells contending for the same medium. Each cell includes a respective plurality of member stations. If an access point has no traffic, it will transmit a short, preemptive pegging packet and reset its backoff timer. In this manner, no gaps longer than the distributed coordination function (DCF) Interframe Space (DIPS) are left idle. This prevents other stations from using DCF contention to seize the channel, until all access points have completed one contention-free session (CFS) per periodic cycle. | 01-09-2014 |
20140254555 | METHOD AND APPARATUS FOR IMPLEMENTING A BLANKET WIRELESS LOCAL AREA NETWORK CONTROL PLANE - A method and apparatus for maintaining a connection between a wireless transmit/receive unit (WTRU) and a blanket wireless local area network (BWLAN) are described. An inter-working function (IWF) entity in a given network access point (NAP) of the BWLAN maintains lists of WTRUs in respective states. Furthermore, the given NAP maintains a list of neighbor NAPs, and operates in accordance with a selected WTRU mobility protocol. The states may include a “not aware” (NA) state in which the given NAP is actually not aware of a particular WTRU, an “active transmit” (AT) state in which the given NAP is actively transmitting to a particular WTRU, and a “neighbor range” (NR) state for WTRUs indicated in an update report from neighbor (URN) message that the given NAP was not aware of. The WTRU mobility protocol may be a push mobility protocol or a poll mobility protocol. | 09-11-2014 |
20140301291 | HYBRID COORDINATION FUNCTION (HCF) ACCESS THROUGH TIERED CONTENTION AND OVERLAPPED WIRELESS CELL MITIGATION - A method and system reduce interference between overlapping first and second wireless LAN cells in a medium. Each cell includes a respective plurality of member stations and there is at least one overlapped station occupying both cells. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point transmits a beacon packet containing the inter-cell contention-free period value, which is intercepted at the overlapped station. The overlapped station forwards the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires. | 10-09-2014 |
20140308965 | HYBRID COORDINATION FUNCTION (HCF) ACCESS THROUGH TIERED CONTENTION AND OVERLAPPED WIRELESS CELL MITIGATION - A method and system reduce interference between overlapping first and second wireless LAN cells in a medium. Each cell includes a respective plurality of member stations and there is at least one overlapped station occupying both cells. An inter-cell contention-free period value is assigned to a first access point station in the first cell, associated with an accessing order in the medium for member stations in the first and second cells. The access point transmits a beacon packet containing the inter-cell contention-free period value, which is intercepted at the overlapped station. The overlapped station forwards the inter-cell contention-free period value to member stations in the second cell. A second access point in the second cell can then delay transmissions by member stations in the second cell until after the inter-cell contention-free period expires. | 10-16-2014 |