Canon Kabushiki Kaisha

Makoto Umehara

Tomoyuki Takada

Naoto Takahashi

Wataru Tachiwa

Hitoshi Asai

Noriyuki Suzuki

Kazuki Takemoto

Hiroichi Yamaguchi

A communication apparatus is capable of using a method of transmitting a signal using a plurality of wireless links, based on confirmation that a wireless medium related to one wireless link among the plurality of wireless links varying in frequency channels is idle for a random backoff time determined by a first method, and a method of transmitting a signal using one wireless link, based on confirmation that a wireless medium related to the one wireless link is idle for a random backoff time determined by a second method, wherein an expectation value of the random backoff time determined by the first method is larger than an expectation value of the random backoff time determined by the second method.

Communication apparatus capable of transmitting signal over multiple wireless links, communication method, and storage medium

The invention provides a mechanism for reducing residual frequency differences in distributed MIMO using a slave trigger, and increasing synchronization precision between APs. The communication device, which constitutes a wireless network by cooperating with another communication device, has a transmission unit for transmitting a frame for synchronization to the other communication device to cooperate with the other communication device. The transmission unit includes: a setting unit that sets a value exceeding 4 as a repetition number for an EHT Long Training Field (EHT-LTF) in a preset position of an EHT Signal Field (EHT-SIG-A) of a frame for synchronization; and a generation unit that generates a frame for synchronization, the frame including EHT-LTFs whose quantity is the set repetition number. The transmission unit transmits the generated frame to the other communication device.

Communication device and method for controlling same and non-transitory computer-readable storage medium

A communication device communicates a physical (PHY) frame including a preamble and a data field. The preamble includes a Legacy Short Training Field (L-STF), a Legacy Long Training Field (L-LTF), a Legacy Signal Field (L-SIG), an EHT Signal Field (EHT-SIG-A), an EHT Short Training Field (EHT-STF), and an EHT Long Training Field (EHT-LTF), and the EHT-SIG-A includes fields indicating a modulation scheme and information indicating which one of a UC (Uniform Constellation) scheme and an NUC (Non Uniform Constellation) scheme is used as the modulation scheme, and the data field includes data that has undergone modulation corresponding to the modulation scheme and the information indicated by the fields.

Communication device, communication method, and computer-readable storage medium

A communication device that supports first and second communication standards using an OFDMA (Orthogonal Frequency Division Multiple Access) technique allocates, based on a frequency resource that has been allocated for a first other communication device in accordance with the first communication standard that uses a first pattern for allocating a frequency resource, a frequency resource for a second other communication device that conforms to the second communication standard that uses a second pattern for allocating a frequency resource. The communication device specifies, from among frequency resources in the second pattern, a second frequency resource that partially or entirely overlaps with a first frequency resource that has been allocated to the first other communication device, and allocates a frequency resource that are not included in the second frequency resource in the second pattern to the second other communication device.

Communication device, control method, and storage medium

There is provided a wireless communication apparatus that is able to perform a first wireless communication and a second wireless communication, the second wireless communication having power consumption lower than that of the first wireless communication. The wireless communication apparatus receives, from another wireless communication apparatus through the second wireless communication, information indicating a channel which the another wireless communication apparatus is able to use in the first wireless communication, selects a communication parameter to be provided to the another wireless communication apparatus based on the received information, the communication parameter being required by the another wireless communication apparatus to connect to an apparatus that forms a network in which the first wireless communication occurs; and transmits the selected communication parameter to the another wireless communication apparatus through the first wireless communication.

Wireless communication apparatus, method of controlling the apparatus, and non-transitory computer-readable storage medium

A communication device communicates a physical (PHY) frame including a preamble and a data field. The preamble includes a Legacy Short Training Field (L-STF), a Legacy Long Training Field (L-LTF), a Legacy Signal Field (L-SIG), an EHT Signal Field (EHT-SIG-A), an EHT Short Training Field (EHT-STF), and an EHT Long Training Field (EHT-LTF) and the EHT-SIG-A includes fields indicating a modulation scheme and information indicating which one of a UC (Uniform Constellation) scheme and an NUC (Non Uniform Constellation) scheme is used as the modulation scheme, and the data field includes data that has undergone modulation corresponding to the modulation scheme and the information indicated by the fields.

There is provided a wireless communication apparatus that is able to perform a first wireless communication and a second wireless communication, the second wireless communication having power consumption lower than that of the first wireless communication. The wireless communication apparatus receives, from another wireless communication apparatus through the second wireless communication, information indicating a channel which the another wireless communication apparatus is able to use in the first wireless communication, selects a communication parameter to be provided to the another wireless communication apparatus based on the received information, the communication parameter being required by the another wireless communication apparatus to connect to an apparatus that forms a network in which the first wireless communication occurs; and transmits the selected communication parameter the another wireless communication apparatus through the first wireless communication.

A communication apparatus, method of communication, and storage medium storing a computer program are provided. The communication apparatus selects, based on a first signal received from another apparatus that belongs to a BSS (Basic Service Set) complying with IEEE802.11 standard, a first or second mode. In the first mode, a first NAV (Network Allocation Vector) and a second NAV are maintained. In the second mode, one NAV is maintained. The first and second NAVs are updated based on signals received from another apparatus that does belongs to a first BSS, or does not belong to the first BSS, respectively. If the first mode is selected and the first NAV is not zero, the second NAV is zero, and a Trigger Frame (TF) complying with IEEE802.11ax standard is received, the communication apparatus responds to the TF. If the second NAV is not zero, the communication apparatus does not response to the TF.

Communication apparatus that permits high frequency utilization efficiency while reducing interference, control method, and storage medium

A display obtains a first image by image capturing, receives, from an external apparatus, a second image generated based on the first image, determines a communication quality with the external apparatus in reception of the second image, and controls to display the second image on a display unit until a value indicating a degree of degradation of the communication quality exceeds a first threshold as a result of determination, and display the first image on the display unit when the value indicating the degree of degradation of the communication quality exceeds the first threshold. The display controls to display the first image until the value indicating the degree of degradation of the communication quality becomes smaller than a second threshold smaller than the first threshold after exceeding the first threshold.

Display, control method, and storage medium

A communication apparatus includes a detection unit configured to detect received powers of a plurality of radio signals received during a first predetermined time period from another apparatus, and a transmission unit configured to transmit by proxy identification information of the another apparatus using a detection result by the detection unit as at least one condition.

Communication apparatus, control method for communication apparatus, and storage medium storing program

A burst signal generator generates a burst signal that is a variable length portion whose length changes in accordance with fluctuations in data input at a predetermined period. An OFDM modulator generates an OFDM signal (including a guard interval portion and an effective symbol portion) that is a fixed length portion containing data corresponding to n (n is a positive integer) times or 1/n of the predetermined period. A frame includes the variable length portion and the fixed length portion. This makes a transmission signal actually have a frame period almost equal to the period of a signal synchronized with the clock of a player, including the fluctuations.

Transmission apparatus and method

A communication apparatus performs communication of data using assigned time slots within a frame. In a case where data cannot be transmitted in a transmission time slot that has been assigned in order to transmit data, a time slot later than this transmission time slot is reserved as a time slot used to transmit the data, this later time slot being reserved within the frame having the transmission time slot in which the data cannot be transmitted.

Communication apparatus, communication system, communication apparatus control method and non-transitory computer-readable storage medium

A communication system including a parent station and a plurality of child stations, the parent station and the plurality of child stations being line-connected or loop-connected in a plurality of stages, and the parent station comprises a decision unit configured to decide, based on information representing states of the plurality of child stations, which one a first data relay method of transmitting data to a subsequent station in accordance with a clock reproduced from data received from a preceding station and a second data relay method of transmitting data to the subsequent station in accordance with a local clock generated in a local station should be employed by each of the plurality of child stations.

Communication system, method of controlling the same, and storage medium

A transmission apparatus for performing an orthogonal frequency division multiplexing (OFDM) transmission generates an OFDM symbol in which a modulation parameter used at a time of transmitting data is arranged in a subcarrier of a direct current component and transmits a transmission frame including the generated OFDM symbol. A receiving apparatus calculates an average value in an effective symbol period within the OFDM symbol included in the transmission frame received, extracts the modulation parameter arranged in the subcarrier of the direct current component based on the calculated average value, and performs OFDM demodulation processing using the extracted modulation parameter.

Communication system, transmission apparatus, and receiving apparatus

Data is transmitted by using continuous frames each of which includes a variable-length part having a length that varies depending on an input period and a fixed-length part containing data of one input period. The transmitted continuous frames are received, a frame period is detected, and data is reproduced based on the detected frame period.

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Kawasaki, Japan

Makoto Umehara