Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station, a parameter switch configuration that indicates at least one parameter switching pattern associated with two or more values of a configuration parameter, the parameter switching pattern corresponding to a periodic uplink communication and a periodic downlink communication. The UE may communicate, based at least in part on the parameter switching pattern, with at least one wireless communication device based at least in part on the periodic uplink communication and the periodic downlink communication. Numerous other aspects are described.

Abstract: A system and method for filtering chirp noise as it passes through a Radio over Internet Protocol (RoIP) gateway in a communication network is disclosed. Radio signals often include a short burst of chirp noise. Incoming signals are buffered and any chirp noise is detected. A chirp filter performs the filtering operation to remove chirp signal while ensuring true audio is not clipped. Without audio clipping the integrity of the audio signals are preserved.

Abstract: A user equipment and a method for handling a switching time period of downlink (DL)-uplink (UL) switching for half duplex-frequency division duplex operation are provided. The method includes: receiving a first configuration for a first active bandwidth part (BWP) with a first sub-carrier spacing (SCS), the first active BWP being one of an active UL BWP and an active DL BWP; receiving a second configuration for configuring a second active BWP with a second SCS, the second active BWP being another one of the active UL BWP and the active DL BWP; receiving a third configuration for the switching time period, the switching time period having a unit of symbol; performing communication with a Base Station (BS) on the first active BWP with the first SCS; and performing, after the switching time period, communication with the BS on the second active BWP with the second SCS.

Abstract: A method and system to control configuration of dual-connectivity service a user equipment device (UE), wherein the dual-connectivity service including the UE being served concurrently by a master node (MN) over a first connection and by a secondary node (SN) over a second connection. An example method includes (i) identifying multiple pairs of access nodes as candidate pairs of access nodes to be the MN and SN for the dual-connectivity service, (ii) for each identified pair, determining an inter-access-node communication delay, (iii) comparing the determined inter-access-node communication delays of the identified pairs and, based on the comparing, selecting one of the identified pairs to be the MN and SN for the dual-connectivity service, and (iv) causing the dual-connectivity service to be set up for the UE with the selected pair of access nodes being the MN and SN for the dual-connectivity service.

Abstract: Disclosed is an RS-485 circuit, which includes an RS-485 interface chip, a start detector, a control module and a counter. The RS-485 interface chip includes a data input terminal and an enable terminal, wherein the data input terminal is configured to receive a data signal, the enable terminal is configured to receive a start signal or a switching signal to make the RS-485 interface chip in a data transmitting state or a data receiving state. The start detector is configured to detect a first signal edge of the data signal to generate the start signal to the enable terminal. After detecting the first signal edge of the data signal, the control module outputs first counting information. The counter is configured to count based on the first counting information, and output the switching signal to the enable terminal when the counter expires.

Abstract: [Problem] When a communication apparatus that is the communication partner is called via a relay device, the transmission control mode of a voice signal can be switched according to the capability of the communication partner. [Solution] A relay device (2) includes a telephone relay unit (3), a network communication relay unit (4), and a wireless communication relay unit (5). The wireless communication relay unit (5) includes a plurality of external apparatus interfaces, and an analog repeater (25), a digital repeater (27), or the like is connected to each external apparatus interface. If an SIP telephone (20) has called an analog transceiver (27), the relay device (2) obtains the address and apparatus type of the analog transceiver (27) from call information, and transmits a voice signal to the analog transceiver (27) using a transmission control mode (VOX mode) that suits the analog transceiver (27).

Abstract: Methods, systems, and devices for wireless communications are described. A user equipment (UE) may identify a multi-mode capability for communications by the UE within a frequency band, such that that UE may be capable of operating in any one of a half duplex time division duplex (TDD) mode and a full duplex frequency division duplex (FDD) mode within the frequency band. The UE may then transmit an indication of the multi-mode capability to a base station. The UE may receive, from the base station and responsive to the transmission of the indication, a communication format configuration that includes a partitioning between TDD mode communications and FDD mode communications for the frequency band.

Abstract: The present disclosure relates to a communication method and system for converging a 5th-Generation (5G) communication system for supporting higher data rates beyond a 4th-Generation (4G) system with a technology for Internet of Things (IoT). The present disclosure may be applied to intelligent services based on the 5G communication technology and the IoT-related technology, such as smart home, smart building, smart city, smart car, connected car, health care, digital education, smart retail, security and safety services. The present invention suggests a method for transmitting and receiving signals satisfying a maximum delay time, and a method and a device for effectively processing signals that are influenced by the transmission and reception of the signals satisfying the maximum delay time.

Abstract: A method and system to control configuration of dual-connectivity service a user equipment device (UE), wherein the dual-connectivity service including the UE being served concurrently by a master node (MN) over a first connection and by a secondary node (SN) over a second connection. An example method includes (i) identifying multiple pairs of access nodes as candidate pairs of access nodes to be the MN and SN for the dual-connectivity service, (ii) for each identified pair, determining an inter-access-node communication delay, (iii) comparing the determined inter-access-node communication delays of the identified pairs and, based on the comparing, selecting one of the identified pairs to be the MN and SN for the dual-connectivity service, and (iv) causing the dual-connectivity service to be set up for the UE with the selected pair of access nodes being the MN and SN for the dual-connectivity service.

Abstract: An apparatus may comprise a processing resource operatively coupled to a memory resource and a frame determination component operatively coupled to the processing resource and the memory resource. The frame determination component may cause a counter corresponding to a particular station associated to the apparatus to be stored in the memory resource, the counter to be incremented in response to receipt of a transmission frame containing an invalid starting sequence number (SEN) and a deauthentication frame to be transmitted in response to receipt of a threshold number of transmission frames containing the invalid.

Abstract: A communication system including two communication nodes communicably connected in a full duplex communication mode via the same communication line is provided.

Abstract: Certain aspects of the present disclosure provide apparatus and method for wireless communication. For example, the method generally includes receiving signaling indicating a first subframe configuration, the first subframe configuration corresponding to a subframe with a first number of symbols in an uplink pilot time slot (UpPTS), receiving signaling indicating a second configuration, the second configuration indicating a second number of symbols in the UpPTS, generating a frame comprising the UpPTS having the first number of symbols corresponding to the first subframe configuration, the UpPTS including one or more SRSs corresponding to the second configuration, and transmitting the frame comprising the UpPTS.

Abstract: Bidirectional transmission is performed by switching transmission directions of a serial transmission path. A transmission system includes the first device that includes a transmission circuit which performs transmission to the second device through the transmission path, and a transmission direction reversal control unit which opens the transmission path after making a request for reversal of a transmission direction in the transmission path to the second device, and reverses the transmission direction at the transmission circuit in response to permission for reversal from the second device.

Abstract: Methods, systems, and devices for wireless communications are described. A central access node (CAN) may manage and schedule resources for a wireless mesh network. The CAN may transmit a first message to a relay access node (AN) to expedite transmission of a priority communication in the wireless mesh network. The first message may provide configuration information for modifying a preconfigured schedule to expedite the transmission of the priority communication. For example, the first message may provide configuration information to modify a preconfigured schedule to allow a first network node to transmit the priority communication to a second network node during a reserved time period. The relay AN may generate a second message regarding the modified schedule and transmit the second message to the second network node.

Abstract: A multi-port configuration system includes a network switch including a plurality of ports and a user device that is configured to couple to the network switch. Each of the plurality of ports is configured to operate in at least one of a plurality of modes. A congruent graphical representation of the network switch is displayed on the user device, and a selection of a group of ports of the plurality of ports is received. Based on the received selection of the group of ports, available configuration settings for the group of ports are displayed on the user device. A configuration settings selection, selected from the available configuration settings, for configuring the group of ports is received. The configuration settings selection is provided to the network switch to configure the group of ports.

Abstract: Disclosed in the present invention is a carrier communication method, device and system of low-voltage power lines, wherein, the carrier communication method includes: acquiring communication data comprising user data transmitted during communication and frame control data for assisting decoding of the user data; encoding the communication data using orthogonal space-time block codes and generating multipath transmission signals, in the case of unknown channel status; and transmitting the multipath transmission signals to an electric energy meter respectively via three-phase power lines. The present invention fully employs the characteristic of distinct inter-phase coupling of electrical signals at medium-and-high frequencies along power lines, and adopts various space-time encoding and decoding technologies, thereby improving the reliability of power line carrier communication between the concentrator and the electric energy meter.

Abstract: A network device, based on received location from a first user equipment (UE) and a second UE may determine that the first UE and the second UE are in proximity to each other. Based on the proximity determination, the network device may provide at least one of the first and second UE uplink LTE resources for transmission, wherein the transmission is associated with a group of UEs.

Abstract: Provided by the present invention are a data transmission method and a terminal, and the method comprises: acquiring data to be sent comprising N data frames; acquiring a bit sequence of an ith data frame; sending X waveform sequences corresponding to bits in the bit sequence of the ith data frame; detecting a level change of a receiving port after completion of sending the X waveform sequences; determining Y waveform sequences of received data; determining a bit sequence of the received data; acquiring a bit sequence of an (i+1)th data frame when the bit sequence at least comprises a flag bit for at least indicating success of receiving data; sending Z waveform sequences corresponding to bits in the bit sequence of the (i+1)th data frame until all the N data frames of the data to be sent are sent.

Abstract: Disclosed is a terminal device that is capable of taking an advantage of increasing transmission capacity in the FD transmission as much as possible by selectively using the FD transmission or the HD transmission in a multi-cell communication environment in consideration of a relationship with other neighboring nodes (base stations and terminals). Also disclosed is a method of operating the terminal device.

Abstract: A method and a system for multi-user transmission in a network, comprising at least on network control center NCC and one or more terminals, wherein the method comprises at least the following steps: determining the number of 4D-TDMA carriers as a function of the number and needs of the terminals, determining the type (SCPC or TDMA) and frequency band Bi of each of the 4D-TDMA carriers as a function of the terminals transmitting on the carriers, for each frame, dividing the band B into PTDMA transmission channels and into PSCPC service channels, each channel consisting of frames comprising a plurality of slots, STDMA slots and SSCPC slots, dynamically allocating a plurality of slots of a 4D-TDMA carrier according to the services required by each terminal, configuring the coding and modulation scheme of each slot by taking account of the quality of the received signals.

Abstract: Half duplex (HD) frequency division duplexing (FDD) in a wireless transmit-receive unit (WTRU) using a single oscillator (SO) for uplink (UL) and downlink (DL), which may contribute to reduced costs of implementation. Approaches to the resolution of scheduling issues which may result from increased switching time versus implementations using separate oscillators are discussed, including indication of SO-HD-FDD capability, scheduling for collision avoidance, enhanced node-b (eNB) receiver implementations, link adaptation for missed detected physical downlink control and shared channels, collision handling, DL measurement, and burst based transmissions.

Abstract: Push to talk (PTT) devices that communicate packet-based voice communications are disclosed. An example PTT device receives voice packets via a packet-based communication network from another PTT device. Voice information in the received voice packets are used to reconstruct the voice communication. The receiving PTT device is able to identify an occurrence of at least one delayed, corrupted or lost voice packet, and then communicate a packet re-transmit request to the other PTT device requesting a replacement voice packet that has a portion of the voice communication that is identical to the voice communication portion of the delayed, corrupted or lost voice packet. The voice communication may then be repaired based on the received replacement voice packet. While the voice communication is being repaired, a comfort tone may be generated so that the listener of the PTT device understands that the voice communication is being repaired.

Abstract: Systems, methods, and other embodiments associated with a method for performing auto-negotiation using a single conductive path are described. In one embodiment, a method includes performing, with a first device, auto-negotiation in half duplex mode with a second device by way of a single conductive path. The single conductive path connects the first device to the second device.

Abstract: Methods and apparatus for Ethernet auto-negotiation (AN) with parallel detect for 10G DAC or other non-auto-negotiated modes. AN base pages are transmitted from an Ethernet apparatus to advertise the ability to support at least one Institute of Electrical and Electronics Engineers (IEEE) 802.3 Ethernet specification supporting AN. A receiver and associated processing circuitry is configured to perform two detection modes in parallel, including a first detection mode that looks for a valid signal transmitted from an Ethernet link peer that does not support AN and a second detection mode looking for AN pages from an IEEE 802.3 Ethernet link peer that supports AN. If the link peer does not support AN, an Ethernet link is set up to use signaling in accordance with the Ethernet specification that does not support AN. If the link peer supports AN, an Ethernet link is set up using a corresponding IEEE 802.3 Ethernet link supporting AN. Supported non-AN Ethernet links include 10G DAC links.

Abstract: Systems and apparatuses involve implementing methods that may include receiving, by enhanced user equipment (eUE), an assignment of Resource Blocks (RBs) from an eNodeB (eNB), wherein the eUE is configured to receive full-duplex transmissions; for each assigned RB, measuring interference caused by uplink transmissions from one or more legacy UEs; and reporting, to the eNB, the measured interference. The present implementations may provide an eUE-based approach, an eUE and eNB interactive approach, an eUE baseband approach, and an eUE analog approach to reducing interference for full duplex enabled mobile devices.

Abstract: Provided herein is an apparatus for data processing, the apparatus including a receiving module configured to receive first data; a data processing module configured to process the first data received from the receiving module, to generate second data including meta data of the first data, and third data including the first data with its data type changed to an array type; and a mapping module configured to change a system of the first data and second data received from the data processing module to generate fourth data and fifth data, and to generate sixth data including mapping data of between the first data and fourth data and between the second data and fifth data.

Abstract: A slave device is realized that establishes a link with a master device or another slave device such that a large link delay hardly occurs. The slave device includes a PHY unit, a COM unit, and a MPU unit. The PHY unit starts an operation according to the specification of the AutoMDI/MDI-X function when the slave device is turned on or the PHY unit itself is reset. After a predetermined time period has elapsed, the MPU unit resets the COM unit, and the PHY unit is reset in response to the reset of the COM unit.

Abstract: Systems, methods, and other embodiments associated with a method for performing auto-negotiation using a single conductive path are described. In one embodiment, a method includes performing, with a first device, auto-negotiation in half duplex mode with a second device by way of a single conductive path. The single conductive path connects the first device to the second device.

Abstract: Interference may be determined between user equipment (UE) based on distance between the UEs and location information. Half duplex communication on orthogonal frequency division multiplexing (OFDM) resources may be scheduled based on the determined interference.

Abstract: A first near field communication (NFC) circuit includes an antenna, a charging circuit, a transceiver circuit, and a transmission delay circuit. The antenna is configured to inductively couple to signals emitted by a second NFC circuit. The charging circuit is configured to output power provided by the inductive coupling through the antenna to the signals emitted by the second NFC circuit. The transceiver circuit is configured to be powered by the charging circuit to transmit data for receipt by the second NFC circuit. The transmission delay circuit is configured to be powered by the charging circuit and control the transceiver circuit to delay transmission of the data until expiration of a defined delay time after the transceiver circuit has become sufficiently powered on to operate to transmit the data. Related accessories for user equipment, user equipment, and methods are disclosed.

Abstract: Described is a communication device which includes a receiver receiving a multicast communication including audio data and identification data identifying an initiator of the multicast communication, a memory, an audio output, a processor processing the multicast communication, sending the processed audio data to the audio output to be played to a user, sending the identification data to the memory to be stored and initiating a unicast communication with the initiator based on the identification data and a transmitter transmitting the unicast communication to the initiator.

Abstract: A system is provided for modeling and analysis of cybersecurity threats may include a data flow diagram (DFD) creator, threat indicator and threat analyzer. The DFD creator may identify elements of an information system, and compose a DFD including nodes and edges representing components and data flows of the information system. The threat indicator may identify a cybersecurity threat to a particular element of the information system, and add a secondary node representing the cybersecurity threat to the DFD to thereby produce a threat-model DFD for the information system. In metadata associated with the nodes, edges and secondary node, the DFD creator and threat indicator may provide structured information including attributes of the components, data flows and cybersecurity threat. And the threat analyzer may perform an analysis of the cybersecurity threat based on the threat-model DFD and metadata associated with the nodes, edges and secondary node thereof.

Abstract: A first network device may determine a first auto-negotiation capability associated with the first network device. The first auto-negotiation capability may indicate whether the first network device is configured to establish a communication link with a second network device using auto-negotiation of transmission capabilities. The first network device may determine a second auto-negotiation capability associated with the second network device. The second auto-negotiation capability may indicate whether the second network device is configured to establish the communication link with the first network device using auto-negotiation of the transmission capabilities. The first network device may determine that an auto-negotiation process failed to establish the communication link between the first network device and the second network device.

Abstract: Aspects of a method and system for extended range Ethernet link discovery signaling are provided. A local PHY may detect of one or more active twisted-pair wires in a remote PHY in extended range applications. The local PHY may determine whether to operate as a master or slave based on detected pairs. When operating as a master device, the local PHY may correct twisted-pair wire swap information received from the remote PHY before communicating an encoded link length value to the remote PHY. When operating as a slave device, the local PHY may transmit encoded twisted-pair wire swap information to the remote PHY before recovering a link length value communicated from the remote PHY. The local PHY may communicate supported operating modes based on the link length value to the remote PHY. Moreover, the local PHY may enable establishing a common full duplex operating mode with the remote PHY.

Abstract: An apparatus includes an NFC circuit and an electrically conductive layer. The NFC circuit includes an antenna configured to inductively couple to signals emitted by another NFC circuit, a charging circuit configured to output power provided by the inductive coupling through the antenna to the signals emitted by the other NFC circuit, and a transceiver circuit configured to be powered by the charging circuit to transmit data for receipt by the other NFC circuit. The electrically conductive layer is removable from being on the NFC circuit, and while the electrically conductive layer is on the NFC circuit the transceiver circuit is prevented from transmitting. The electrically conductive layer can include a removable conductive sticker that electrically connects to one or more locations on the antenna, to a ground plane of the NFC circuit, and/or to another circuit node of the NFC circuit to prevent the transceiver circuit from transmitting.

Abstract: Half-duplex (HD) operations enable low cost implementations of LTE terminals. Traditionally, HD operations may be linked to a particular frequency band which may not allow a mix of full-duplex (FD) and HD terminals in the same frequency band. Therefore, certain aspects of the present disclosure provide techniques for enabling coexistence, in a given frequency band, of HD and FD terminals, by introducing frequency bands designated for HD operation and overlapping existing frequency bands designated for FD operation.

Abstract: There is provided a base station including a communication unit for communicating with a user equipment according to a frame format where subframes for uplink and subframes for downlink are structured in a time division manner, and a scheduler for moving a boundary between a subframe for downlink and a subframe for uplink. The communication unit wirelessly communicates with another base station by using a subframe between the boundary before movement by the scheduler and the boundary after the movement.

Abstract: A method and apparatus which allows dynamic TDD UL/DL configuration that is able to adapt to an instantaneous traffic situation. The values of at least one uplink/downlink configuration indication bit in a predetermined region in a received downlink time division duplex subframe of wireless data transmission are examined. A time division duplex uplink/downlink configuration for a predetermined configuration period is determined based on the examined values.

Abstract: A wireless communication device for enabling half-duplex communication is described. The wireless communication device includes a processor and instructions stored in memory that is in electronic communication with the processor. The wireless communication device receives an indicator. The wireless communication device also determines a half-duplex frame structure with a regular uplink (UL) and downlink (DL) switching pattern based on the indicator. The half-duplex frame structure includes at least one UL subframe group including one or multiple consecutive UL subframes and at least one DL subframe group including one or multiple consecutive DL subframes. The wireless communication device further receives DL information in at least one of the DL subframes. The wireless communication device additionally sends UL information in at least one of the UL subframes.

Abstract: This disclosure relates to methods and devices for changing dynamic display effect of mobile phone application by way of voice control. The method includes a recording step, recording an audio file of a voice external to a mobile phone; a judgment step, calculating a voice energy value linearly dependent upon sound volume in the audio file, comparing the voice energy value to a pre-set noise threshold value and performing a rate calculation step when it is greater than the pre-set noise threshold value; a rate calculation step, calculating a corresponding changing rate according to the voice energy value; and an application display step, setting the changing rate of the current application as a calculated changing rate and displaying same for the current application. This disclosure increases the approaches whereby a user controls the dynamic application changing effect and it can be applied to a mobile phone without a touch screen.

Abstract: Described is a technology by which a scalable distributed file system is provided by deploying intelligent storage devices that are directly connected to the network. A server receives a request for data from a requester, and sends corresponding requests to the storage devices. The storage devices send data blocks directly to the requester instead of back to the server, while identifying the server as the sender, e.g., by programming a switch to participate in such an operation.

Abstract: A data processing apparatus includes a plurality of computation devices connected to each other by a communication path. Each of the computation devices includes: a switching section provided to each of terminals and switchable between an upper layer use state in which communication is performed by a communication section between a given terminal of a plurality of terminals and a corresponding internal path and there is no connection performed by a bypass section between a corresponding pair of the plurality of the terminals, and an upper layer non-use state in which communication is not performed by a communication section between the given terminal of the plurality of the terminals and the corresponding internal path and connection is performed by the bypass section between the corresponding pair of the plurality of the terminals.

Abstract: Systems and techniques are described for scheduling communication by half-duplex devices. One or more half-duplex devices informs a base station that it is capable only of half-duplex operation. For each such device, the base station configures a transmit/receive pattern comprising sequences of uplink and downlink subframes and applies the pattern to the device. The half-duplex device may receive during a downlink subframe and may transmit during an uplink subframe. Uplink and downlink subframes within a pattern are separated by an offset based at least in part on a number of hybrid automatic repeat request processes.

Abstract: The present invention relates to a wireless communication system. More particularly, the present invention relates to a method and apparatus for transceiving a signal in a half-duplex manner in a wireless communication system in which a first carrier and a second carrier are aggregated. The method comprises: a step of receiving a downlink signal on a first carrier during a first symbol period of a specific subframe; and a step of transmitting an uplink signal on a second carrier during a second symbol period of the specific subframe. The specific subframe is set as a downlink subframe in the first carrier and as an uplink subframe in the second carrier. The specific subframe is set to transmit an uplink reference signal.

Abstract: An energy efficient Ethernet physical layer (PHY) device including an EEE control module configured to generate a control signal to transition the PHY device into a low power consumption mode based an operating condition, and a pause frame generator module responsive to the control signals to generate a pause frame. The pause frame generator module is configured to send the pause frame to a media access control (MAC) device to reduce an incoming flow of data packets from the MAC device to the PHY device for a pause time duration. In operation, the pause frame generator module generates the pause frame including a pause time indicating the length of time for the PHY device to be in the low power consumption mode. The value of the pause time for each pause frame is determined adaptively based on the amount of data traffic to be transmitted from the PHY device.

Abstract: The disclosure relates to controlling uplink transmissions according to closed loop techniques such as closed loop uplink transmit diversity and uplink multiple-input multiple-output (MIMO). An exemplary method for use in a user equipment (61) configured for multi-antenna transmissions comprises a step of receiving (62), in a downlink channel, pre-coding vector information indicating a pre-coding vector for uplink transmission. The method further comprises a step of determining (63) whether the pre-coding vector indicated by the received pre-coding vector information is reliable or unreliable and steps of applying (64) the pre-coding vector indicated by the received pre-coding vector information for uplink transmission only if the pre-coding vector is determined to be reliable and applying (66) a pre-determined pre-coding vector when the pre-coding vector indicated by the received pre-coding vector information is determined to be unreliable.

Abstract: Disclosed are new methods of fax-over-IP (FoIP), modem-over-IP (MoIP) or text-over-IP (ToIP) call establishment based on detecting a combination of contra-propagating signals from calling and answering terminals for autonomous connection of media gateways.

Abstract: In one embodiment, a sender in a shared-communication network determines whether a pending frame is low-latency or high-throughput, and sets a maximum transmission unit (MTU) of the pending frame as a first MTU in response to a low-latency frame and a longer second MTU in response to a high-throughput frame. In another embodiment, a receiver receives a data frame from a sender according to an MTU, and determines a trigger for adjusting the MTU based on latency requirements. In response to the trigger, the receiver sets an interrupt flag in a link-layer acknowledgment for the received data frame. In still another embodiment, a sender determines a pending low-latency data frame to send to a receiver operating according to an MTU, and sends a control message to the receiver to indicate the pending low-latency data frame and an adjusted MTU.

Abstract: Disclosed herein are systems, methods, and computer-readable storage media for enabling improved cancellation of self-interference in full-duplex communications, or the transmitting and receiving of communications in a single frequency band without requiring time, frequency, or code divisions. The system estimates the signal strength and phase of a self-interference signal, generates a cancellation signal based on this estimate, then uses the cancellation signal to suppress the self-interference before sampling received analog signal. After applying the cancellation signal, the system samples and digitizes the remaining analog signal. The digitized signal is then subjected to additional digital cancellation, allowing for extraction of the desired signal.

Abstract: An object of the invention is to arrange so that the digital signal transmission between specific equipments connected with each other by the transmission line of a fixed standard can be performed securely and satisfactorily. When a digital signal destination is caused to receive a fixed digital signal sent out of a digital signal sender, the digital signal destination acquires at the request of the destination from the digital signal sender data on modes in which the digital signal sender is able to send out the digital signal, and a transmission mode of the digital signal is caused to be set by a command based on the acquired mode data from the digital signal destination. Moreover, when a digital signal destination is caused to receive a fixed digital signal sent out of a digital signal sender, a flag is added to the digital signal sent out of the digital signal sender, which indicates that the transmission rate is being adjusted based on the command from the digital signal destination.