Abstract: In a transmitter (2001), when generating a transmission frame having no limitation to a window size, a batch-transmission-end flag generating circuit (2004) and a sequence number generating circuit (2005) respectively adds a batch-transmission-end flag and a sequence number to the transmission frame. In a receiver, if an omission of a sequence number is detected as a result of analyzing sequence numbers of frames having received from the transmitter (2001), retransmission request is made when receiving a frame whose batch-transmission-end flag indicates the end. In this way, retransmission is possible in data transmission using UI frames, and the communication efficiency can be improved.

Abstract: A transmitter (1) which transmits a predetermined amount of transfer data using an infrared ray includes: a controller (13) for transmitting an SNRM command to the other station without transmitting a station-search command (XID) for searching the other station, the SNRM command including parameters such as maximum transferable speed and maximum receivable data length of the transmitter (1); and a transmission section (14). Consequently, it is possible to shorten a time necessary for a connection between the transmitter and the receiver. This allows shortening a time from the start of communication to the end of the communication in transmitting information data.

Abstract: A plurality of connection frames are transmitted which differ from each other in at least either modulation scheme or transfer rate. Accordingly, a receiving-end device can properly receive a connection frame even in an environment where the connection frame is likely to be affected by noise.

Abstract: A communications device is provided which receives data frames in FIR communications mode even if the device has failed to normally receive a connect frame in SIR communications mode. A communications device according to the invention includes an incoming frame processing section for receiving an SNRM frame and UI frames in different frame formats. The SNRM frame contains a setting for a connection for data communications. The UI frames contain data. The communications device also includes a reception processing section and connect command notification sections. The reception processing section renders a light reception section stand by for reception of the UI frames in FIR communications mode. The connect command notification sections generate a connect command for output to an upper layer. The connect command enables establishing of the same connection when a data frame is received from another communications device as when a connect frame was received from the other communications device.

Abstract: The present invention is a network layer protocol used for free-space optical transmission utilizing an LED or LD as a light source. In order to connect to a device, the network layer issues a connection request command (LAP_con_req2) to a lower layer when the network layer has received a connection request command (LM_con_req1) from an upper layer. Furthermore, when the network layer has received a connection confirmation command reception notification (LAP_con_conf1) from the lower layer, the network layer issues a connection confirmation command reception notification (LM_con_conf2) to the upper layer without issuing a data transfer request command to the lower layer. Accordingly, the invention provides a network layer protocol with which time for a connection or disconnection is reduced.

Abstract: Provided is a communication system including a transmitter and a receiver which carry out communication by establishing connection of their plurality of communication layers. The transmitter generates a connection request containing a command and data required for connecting a number of contiguously adjacent layers among the plurality of communication layers and transmits the connection request to the receiver. The receiver receives a connection request containing a command and data required for connecting a number of contiguously adjacent layers among the plurality of communication layers, extracts the command and data from the connection request, and establishes connection for the plurality of communication layers based on the command and data. In this way, the time taken to establish connection is reduced. Therefore, even when the connection is cut off during the data exchange, the connection can be established again without taking much time, allowing quick recovery of data exchange.

Abstract: A communication apparatus (1) is a primary station for communicating with a secondary station, and includes: a first protocol control section (111) for transmitting, at a time when communication connection is to be established with the secondary station, (i) a station discovery command with which to confirm a presence of the secondary station, and (ii) a first connect request command, after the station discovery command is transmitted, so as to carry out connection processing; second protocol control means (112) for transmitting, at a time when communication connection is to be established with the secondary station, a second connect request command so as to carry out connection processing; and a protocol switching section (113) for (i) causing the first protocol control section (111) to initially transmit the station discovery command, and in a case where a response to the station discovery command has not been received after an elapse of a predetermined time since the station discovery command was transmitt

Abstract: In a client device (1) including OBject EXchange protocol (OBEX), a lower layer processing section (13) below an OBEX processing section (12) generates a pseudo response command for a request command, and notifies the pseudo response command to the OBEX layer processing section (12). This makes it possible for the client device (1) to communicate, via object exchange, with a server device having no transmitting function.

Abstract: The demodulation circuit of the present invention is a demodulation circuit, connected with a plurality of light-receiving sections each for receiving an optical signal and converting the signal into a binary pulse signal, operable to select and demodulate a pulse signal out of pulse signals that are supplied from the light-receiving sections, respectively, the demodulation circuit including: a judgment and selection section for detecting timing with which High level and Low level of each of the pulse signals are switched and for selecting at least one pulse signal based on the timing; and a demodulation section for demodulating the pulse signal selected by the judgment and selection section. Consequently, the demodulation circuit easily selects and demodulates a signal whose jitter component is small out of a plurality of supplied signals.

Abstract: A content transmission device (11) transmits communications data by infrared. The content transmission device (11) includes: a one-way communications section (48) for transmitting the communications data by one-way communications; a two-way communications section (49) for transmitting the communications data by two-way communications; and a control section (40) for selecting which of the one-way communications section (48) and the two-way communications section (49) transmits the communications data.

Abstract: A communication apparatus (1) is a primary station for communicating with a secondary station, and includes: a first protocol control section (111) for transmitting, at a time when communication connection is to be established with the secondary station, (i) a station discovery command with which to confirm a presence of the secondary station, and (ii) a first connect request command, after the station discovery command is transmitted, so as to carry out connection processing; second protocol control means (112) for transmitting, at a time when communication connection is to be established with the secondary station, a second connect request command so as to carry out connection processing; and a protocol switching section (113) for (i) causing the first protocol control section (111) to initially transmit the station discovery command, and in a case where a response to the station discovery command has not been received after an elapse of a predetermined time since the station discovery command was transmitt

Abstract: A communications device is provided which receives data frames in FIR communications mode even if the device has failed to normally receive a connect frame in SIR communications mode. A communications device according to the invention includes an incoming frame processing section for receiving an SNRM frame and UI frames in different frame formats. The SNRM frame contains a setting for a connection for data communications. The UI frames contain data. The communications device also includes a reception processing section and connect command notification sections. The reception processing section renders a light reception section stand by for reception of the UI frames in FIR communications mode. The connect command notification sections generate a connect command for output to an upper layer. The connect command enables establishing of the same connection when a data frame is received from another communications device as when a connect frame was received from the other communications device.

Abstract: A transmitter apparatus transmits transfer data having a predetermined amount to a receiver apparatus. The apparatus includes a data packet generating section dividing the transfer data into multiple divisional data sets; an error detection/correction code adding section adding an error detection code (error detection information) by which an error in the divisional data sets is detected to each of the divisional data sets; and a transmitter section transmitting the multiple divisional data sets to which the error detection code is added all together. Thus, data transfer is very reliable. It takes less time to transfer data.

Abstract: A data transmitter includes (a) first communication means performing data transmission according to IrDA Standard, (b) second communication means performing data transmission that does not comply with the IrDA Standard and (c) means for switching between a process performed by the first communication means and a process performed by the second communication means. The second communication means includes (a) management information transmitting means for sending management information for managing transmission target data according to a data transmission prosecution command from a user, (b) communication capability information receiver means for receiving communication capability information indicating communication capability of a device that has responded to the transmission of the management information and (c) data transmission means for transmitting a packet including the transmission target data on the basis of the communication capability information.

Abstract: In a transmitter (2001), when generating a transmission frame having no limitation to a window size, a batch-transmission-end flag generating circuit (2004) and a sequence number generating circuit (2005) respectively adds a batch-transmission-end flag and a sequence number to the transmission frame. In a receiver, if an omission of a sequence number is detected as a result of analyzing sequence numbers of frames having received from the transmitter (2001), retransmission request is made when receiving a frame whose batch-transmission-end flag indicates the end. In this way, retransmission is possible in data transmission using UI frames, and the communication efficiency can be improved.

Abstract: The communications device of the present invention performs an authentication with the device at the other end automatically or through a simple operation, independently of an authentication scheme supported by the device at the other end. A communications device includes: a connecting section for establishing a connection with the other communications device according to the IrSimple scheme; an authentication section for performing an authentication by the IrSimple scheme; a connecting section for establishing a connection with the other communications device according to the IrDA scheme, an authentication section for performing an authentication according to the IrDA scheme; and a protocol switching section for causing the connecting section to initiate a connection and causing the authentication section to perform an authentication, when an authentication by the authentication section is unsuccessful.

Abstract: A receiver establishes a communication between the receiver and a transmitter that transmits data by a directional wireless communication. While a connection request command which is information for requesting a connection is transmitted from the transmitter to the receiver at a predetermined period, a packet group corresponding to the connection request command is transmitted from the transmitter to the receiver. The receiver includes a receiver connection establishment control section which controls a communication device so that a connection between the transmitter and the receiver is established in accordance with the connection request command, in a case where the connection request information is received from the transmitter while the communication with the transmitter and the receiver is released. This allows the receiver to naturally reproduce streaming data with the use of a directional wireless communication.

Abstract: A two-way transmission system of the present invention is arranged in such a manner that, when a host-side controller confirms the receipt of an IN packet from a USB host, the host-side controller transfers the IN packet to a function-side controller, and receives a DATA packet from the function side. The received DATA packet is temporarily stored in a FIFO. At the time of the receipt of the IN packet again, the host-side controller supplies, to the USB host, the DATA packet stored in the FIFO.

Abstract: In a client device (1) including OBEX, a lower layer processing section (13) below an OBEX processing section (12) generates a pseudo response command for a request command, and notifies the pseudo response command to the OBEX layer processing section (12). This makes it possible for the client device (1) to communicate, via object exchange, with a server device having no transmitting function.

Abstract: A plurality of connection frames are transmitted which differ from each other in at least either modulation scheme or transfer rate. Accordingly, a receiving-end device can properly receive a connection frame even in an environment where the connection frame is likely to be affected by noise.