Abstract: In an 802.11ax network with an access point, a trigger frame offers scheduled and random resource units to nodes for data uplink communication to the access point. To avoid the overall energy level seen by legacy nodes for a communication channel to drop below a detection threshold, the invention provides two tools. First, the scheduled and random resource units may be interleaved over communication channels. Second, unused resource units may be detected, and a node or the access point may send a padding signal on them to increase the overall energy level. The latter may be evaluated during a monitoring period before deciding to emit the signal. As the overall energy level seen by legacy nodes is increased, the risk that such legacy nodes do not detect activity on a 20 MHz channel having only a subpart of its RUs used is reduced. And risks of collisions are consequently reduced.

Abstract: In 802.11ax networks with access points, a trigger frame offers scheduled and random resource units to nodes for data uplink communication to the access points. To make more effective the usage of the network, the access point may design the trigger frame to force the nodes to send some categories of data. Resource units may be defined in trigger frames to be dedicated to small packets or to some access category data. Adjusting the time length of the resource units helps restricting the type of data that can be conveyed by the resource units. Also, using various frequency widths for resource units in the same trigger frame helps reducing padding in the resource units when various traffic types coexist.

Abstract: Compression between two blocks (5, 6) forming a dynamic seal (13) between a rotor (2) and a stator (1) is applied by an inflatable seal (7) located in a groove. When blocks (5 and 6) must be cuttable, in other words divided into two parts to be assembled around the shaft (2), the originally linear seal (7) is wound in the groove and its ends are in contact with each other. It applies a uniform compression around the circumference and its placement does not require major disassembly of the equipment.