Canon Kabushiki Kaisha

Romain Guignard

Pascal Viger

Stéphane Baron

Patrice Nezou

Julien Sevin

Yacine El Kolli

Arnaud Closset

Lionel Tocze

Tristan Halna Du Fretay

Lionel Le Scolan

Philippe Le Bars

Pascal Lagrange

Pierre Visa

Mickaël Lorgeoux

An 802.11ax access point, AP, manage a granted transmission opportunity to schedule multi user uplink and downlink transmissions with non-AP stations. Resource units may also be allocated to non-AP stations for direct link, DiL, transmissions. To efficiently arbitrate between scheduling new MU UL transmissions or DiL transmissions, the AP must know the needs of the non-AP stations. The buffer status report, BSR, either solicited or unsolicited, provides an ACI Bitmap subfield and a Delta TID subfield to signal a number of TIDs for which buffered uplink traffic is declared. The BSR is amended so that these two subfields further signal, in addition to the buffered UL traffic, when there is buffered DiL traffic. Other subfields may provide more information on the amount of buffered DiL traffic.

Buffer status report signaling both buffered uplink traffic and buffered direct link traffic

The present invention concerns a method of wireless communication between a base station and a user equipment, wherein the method comprises: transmitting, by the base station, a data radio bearer configuration; and transmitting packets according to the data radio bearer configuration between the base station and the user equipment; wherein: the data radio bearer configuration comprises a network coding configuration; and the transmitted packets are transmitted according to the network coding configuration.

Method and apparatus for configuring network coding and controlling network coding activation

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.

Trigger frames adapted to packet-based policies in an 802.11 network

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.

Emission of a signal in unused resource units to increase energy detection of an 802.11 channel

802.11ac networks define an operating band made of an ordered series of 20 MHz channels and authorize a restricted number of possible composite channel configurations to be used for data transmission. A method of transmitting data between a source and a receiver in such a wireless network may comprise, at the source: sending, to the receiver, RTS fames to request reservation of a composite channel, the RTS frames including a flag signalling the source supports transmission over un-authorized composite channels, for instance over sub-channels not contiguous within the operating band; receiving, from the receiver in response to the RTS frames, CTS frames acknowledging reservation of un-authorized composite channel configuration, for instance of non-contiguous sub-channels; and then transmitting, to the receiver, data frames on the reserved sub-channels of the un-authorized configuration, for instance on the reserved non-contiguous sub-channels within the operating band.

Non-contiguous channel allocation over multi-channel wireless networks

The present invention relates to a method for generating control signals for an image capture device, the method being performed in a communication device comprising a first slave time generator and a second slave time generator, the communication device being connected to a first remote time server and a second remote time server, the method comprising:

Method for generating control signals for an image capture device

Trigger frames adapted to packet-based policies in an 802.11 network preliminary class

The invention relates to a method and system for simultaneous transmission of data from two or more wireless communication device during a transmission opportunity otherwise reserved for a single communication device. The invention proposes collaboration among the group of communication devices to reserve a transmission opportunity on a composite channel comprising of a plurality of sub-channels for the entire group and to efficiently manage allocation of the sub-channels for simultaneous data transmission from two or more devices. In the main aspect of the invention, the collaboration takes the form of grouping the sub-channels in the reserved composite channel so as to allow two or more stations to transmit data simultaneously over a contiguous frequency band. The collaboration among the group of communication devices may be in a managed or an ad hoc mode. The invention is particularly relevant to the IEEE 802.11 ac communication standard.

Enhanced channel allocation over multi-channel wireless networks

A method of synchronization of a communication device comprising a first and second communication ports, each of the first and second communication port being associated with a respective first and second time system, the method comprising a regular master synchronization process synchronizing regularly the first time system with an external synchronization server according to a time synchronization protocol; a regular slave synchronization process synchronizing regularly the second time system with the first-time system; detecting a loss of synchronization between the first and second time system; determining which of the first and second time system is desynchronized; and synchronizing the desynchronized time system with the other one.

Method and apparatus for synchronizing different communication ports

A method for synchronizing a logical clock in a device comprising a physical clock, an input port, and an output port, the device further comprising a logical clock and a time compensation clock sharing the physical clock, the time compensation clock making it possible to determine a residence time, comprising obtaining a theoretical residence time, during a pre-synchronization phase according to which the logical clock is not synchronized, adding a value representative of the obtained theoretical residence time to a residence time value stored in a synchronization message to be forwarded, during a synchronization phase according to which the logical clock is synchronized, obtaining a residence time and adding a value representative of the obtained residence time to a residence time value stored in a synchronization message to be forwarded, and synchronizing the logical clock as a function of a residence time value stored in a received synchronization message.

Method, device, and computer program for improving synchronization of clocks in devices linked according to a daisy-chain topology

A communication device comprising at least one communication port called reception port and another communication port called forward port, each communication port being associated with a respective clock, the communication device being further configured for computing an offset between the respective clocks associated with the reception and forward ports, and synchronizing the respective clocks based on the computed offset.

Growing community of inventors

Rennes, France

Romain Guignard