JP4396421B2 - Wireless communication system, data transmission apparatus, data transmission method, data processing apparatus, and data processing method - Google Patents

Description

  The present invention relates to a wireless communication system, a data transmission device and a data transmission method, a data processing device and a data processing method, and a computer program that realize a communication operation with low power consumption between devices in a relatively short distance. Back-scatter wireless communication system that performs data communication using transmission of unmodulated carrier from reflected wave reader side and modulation of reflected wave based on switching operation of antenna load impedance on reflector side, data transmission The present invention relates to an apparatus, a data transmission method, a data processing apparatus, a data processing method, and a computer program.

  More specifically, the present invention relates to a wireless communication system, a data transmission device, and a data transmission device that efficiently transmit data using reflected wave transmission from a data transmission device that holds data to a data processing device that performs display processing and other processing of data. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmission method, a data processing device, a data processing method, and a computer program. The present invention relates to a wireless communication system, a data transmission apparatus and a data transmission method, a data processing apparatus and a data processing method, and a computer program.

  By connecting a plurality of devices to the network, it is possible to achieve efficient command and data transmission, sharing information resources, and sharing hardware resources. More recently, wireless networks have attracted attention as systems that release users from wired wiring.

  Examples of standard specifications relating to wireless networks include IEEE (The Institute of Electrical and Engineering Engineers) 802.11, HiperLAN / 2, IEEE 802.15.3, Bluetooth communication, and the like. In recent years, wireless LAN systems have become popular, coupled with the fact that wireless LAN systems have become cheaper and have been built into PCs as standard.

  A relatively small wireless communication system is used for data transmission between a host device and a terminal device in a home or the like. Examples of the host device mentioned here include stationary home appliances such as a television, a monitor, a printer, a PC, a VTR, and a DVD player. Examples of terminal devices include mobile devices such as digital cameras, video cameras, mobile phones, personal digital assistants, and portable music players that want to minimize power consumption. An application of this type of system is uploading image data taken with a mobile phone with a camera or a digital camera to a PC via a wireless LAN.

  For example, a proposal has been made regarding a digital camera that is advantageous in favor of good Bluetooth communication (see, for example, Patent Document 1). The digital camera includes a case and a shutter button provided on the case, and the shutter button is provided at one end in the left-right direction at the upper part of the case. Also, an antenna for Bluetooth communication is provided in the case at the other end in the left-right direction at the top of the case.

  However, the wireless LAN is originally designed and developed on the assumption that it is used in a computer, and its power consumption becomes a problem when mounted on a mobile device. Many of the IEEE802.11b wireless LAN cards currently on the market have a power consumption of 800 mW or more when transmitting and 600 mW or more when receiving. This power consumption is a heavy burden for battery-powered portable devices.

  Even if the wireless LAN function is operated in a limited range and the transmission power is reduced, the power consumption can be reduced by only about 80%. In particular, since transmission from an image input device such as a digital camera to the image display device is in a communication form in which the transmission ratio occupies the entire communication, wireless transmission means with low power consumption is still required.

  Further, the Bluetooth communication has a low transmission speed of 720 kbps at the maximum, which is inconvenient because it takes a long time to transmit an image having a large file size with the recent increase in image quality.

  On the other hand, wireless transmission using reflected waves based on the back scatter method used in RFID realizes low power consumption in a communication mode in which the transmission ratio occupies most of the communication between devices, for example. be able to.

  A back-scatter wireless communication system includes a reflector that transmits data using a modulated reflected wave, and a reflected wave reader that reads data from the reflected wave from the reflector. During data transmission, the reflected wave reader transmits an unmodulated carrier. On the other hand, the reflector transmits data by performing a modulation process corresponding to the transmission data on the unmodulated carrier by using a load impedance operation such as on / off of the end of the antenna, for example. The reflected wave reader side can receive the reflected wave, demodulate and decode it, and acquire transmission data.

  The reflector includes, for example, an antenna that reflects incident continuous wave radio waves, a transmission data generation circuit, and an impedance change circuit that changes the impedance of the antenna corresponding to the transmission data (for example, Patent Document 2). checking).

  In the reflected wave transmission system, the antenna switch for changing the load impedance of the antenna (that is, modulating the reflected wave) is generally composed of a gallium arsenide IC, and its power consumption is several tens of μW or less. The average power when performing data transmission is 10 mW or less in the case of the delivery confirmation method, and data transmission is possible at several tens of μW in the one-way transmission. This is an overwhelming performance difference compared to the average power consumption of a general wireless LAN (see, for example, Non-Patent Document 1). Therefore, even when an information storage terminal device is mounted on a battery-driven mobile device such as a digital camera, the battery life can be greatly extended by reducing the power consumption during the data transfer operation.

  FIG. 21 schematically shows a configuration example of the reflected wave transmission system. The illustrated reflected wave transmission system includes an image transmission device 1 and an image display device 2. The image display device 2 has a function as a reflected wave reader and sends out an unmodulated carrier. On the other hand, the image transmission apparatus 1 has a function as a reflector, and generates a reflected wave obtained by modulating the received unmodulated carrier based on transmission data. Then, the image display device 2 demodulates the reflected wave reflected by the image transmission device 1 into data and displays it on the display unit.

  Portable image transmission devices such as digital still cameras, mobile phones with cameras, and video cameras are equipped with a reflector function, so that the image data to be transmitted can be reflected by the reflected wave transmission method described above. It can be transmitted on In this case, the portable device itself has a feature that it does not need to have a carrier generation source as means for transmitting radio waves, and has an advantage that power consumption is overwhelmingly lower than that of a wireless LAN.

  However, in order to obtain a reflected wave with sufficient reception intensity, the distance between the portable image transmission apparatus and an image display apparatus such as a PC or TV is limited to a short distance of about several meters. For this reason, in a reflected wave transmission system, directivity is given to the antennas of an image transmission device that generates reflected waves, or both the image transmission device and the image display device, and a large antenna gain is obtained in a specific direction. In many cases, the wireless transmission distance is extended.

  FIG. 22 shows a directional antenna in which both the image transmission device and the image display device use an omnidirectional antenna, and in which both the image transmission device and the image display device can obtain a large gain in one direction. This shows the difference in wireless communication distance when using.

  In the figure, the image transmission apparatus 201 and the image display apparatus 202 use omnidirectional antennas, the arrival distance of the reflected wave of the image transmission apparatus 201 is a diagonal line 203, and the arrival distance of the non-modulated carrier of the image display apparatus 202 is a diagonal line. 204. The image transmission apparatus 205 and the image display apparatus 206 use omnidirectional antennas, the arrival distance of the reflected wave of the image transmission apparatus 205 is represented by a hatched line 207, and the arrival distance of the non-modulated carrier of the image display apparatus 206 is the hatched line 208. It is represented by Assume that the distance between the image transmission apparatus 201 and the image display apparatus 202 and the distance between the image transmission apparatus 205 and the image display apparatus 206 are the same.

  In the example shown in FIG. 22, when an omnidirectional antenna is used, the non-modulated carrier 204 of the image display device 202 does not reach the image transmission device 201, and thus the image transmission device 201 generates the reflected wave 203. No communication is established. On the other hand, when a directional antenna is used, both the unmodulated carrier 208 from the image display device 206 and the reflected wave 207 from the image transmission device 205 reach both parties, and communication is established. .

  As described above, in the reflected wave transmission system, the wireless communication distance can be extended by using the directional antenna for the image transmission apparatus or both the image transmission apparatus and the image display apparatus. On the other hand, if the orientation of the image transmission device and the image display device are deviated, there is a risk that communication is not established.

  FIG. 23 shows an example in which the image transmission device 301 using the directional antenna and the image display device 302 are not facing each other. The image transmission apparatus 301 is located in a range where the unmodulated carrier 304 transmitted from the image display apparatus 302 can be received, but the reflection direction of the reflected wave 303 is not directed to the image display apparatus 302. For this reason, the image display apparatus 302 cannot receive the reflected wave 303 and communication is not established.

  As can be seen from the description of FIGS. 22 and 23, in a wireless communication system having directivity, the communicable range is not determined only by the communication distance, and it is difficult for the user to visually determine. A user who performs wireless image transmission needs to align the image transmission apparatus 301 with the image display apparatus 302 in advance before starting the transmission operation.

  Here, when data is transferred between two devices, generally, a file to be transmitted and a file transfer destination are designated in the data transfer source device, and then the file transfer is performed. For example, when an image photographing apparatus such as a digital camera transfers a photographed image to a PC, after the image photographing apparatus is connected to the PC, a file to be transferred is designated, and then a transfer process to the PC is performed. Here, when the image capturing apparatus and the PC are connected by the above-described reflected wave transmission path, the user needs to perform both an operation for adjusting the directivity between both apparatuses and an operation for designating a transfer file. There is.

  FIG. 24 illustrates an example of a communication sequence of the reflected wave transmission system in such a case. Hereinafter, the communication sequence will be described with reference to FIG.

401: The user switches the image transmission apparatus to the data transmission mode from the operation / display unit of the image transmission apparatus.
402: The user switches the image display device to the data reception mode from the operation / display unit of the image display device.
403: The image display apparatus starts continuous transmission of unmodulated carriers.
404: The user selects a transmission file from the operation / display unit of the image transmission apparatus.
405: The user orients the image transmission device in the direction of the image display device.
406: The user presses the send button from the operation / display unit of the image transmission apparatus.
407: The image transmission apparatus transmits a data transmission request packet to the image display apparatus.
408: Upon receiving the data transmission request packet, the image display device stops continuous transmission of the unmodulated carrier.
409: If there is an error in the received data transmission request packet, the image display device generates a NACK. If there is no error and transmission is permitted, a transmission permission packet is generated and transmitted with ASK modulation.
410: When the transmission of the transmission permission packet is completed, the image display device continuously transmits the non-modulated carrier again.
411: Upon receiving the transmission permission packet, the image transmission apparatus transmits a transmission data packet.
412: When receiving the data packet, the image display device stops continuous transmission of the unmodulated carrier.
413: The image display apparatus generates a NACK if there is an error in the received data packet, generates an ACK packet if there is no error, and transmits it with ASK modulation.
414: When the image display device completes the transmission of the ACK / NACK packet, the image display device continuously transmits the unmodulated carrier again.
415: The sequence of 411 to 414 is repeated until there is no transmission data from the image transmission apparatus to the image display apparatus.
416: Transmission of data from the image transmission apparatus to the image display apparatus is completed.
417: When there is still a file to be transmitted, the user selects the next transmission file from the operation / display unit of the image transmission apparatus.
418 to 428 are the same as 404 to 415 described above.

  In this way, in the reflected wave transmission system, every time a file is sent, the user needs to align the image transmission device in the direction of the image display device, and it takes a lot of work when there are several files to be sent. For example, it is very troublesome to repeatedly specify the directivity to the image display device after sequentially specifying the file to be transferred.

JP 2004-56711 A Japanese Patent Laid-Open No. 01-182784 Japanese Patent Application No. 2003-291809 Specification

  An object of the present invention is to suitably perform data communication using transmission of an unmodulated carrier from the reflected wave reader side and modulation of the reflected wave based on an antenna load impedance switching operation on the reflector side. Another object of the present invention is to provide a wireless communication system, a data transmission device and a data transmission method, a data processing device and a data processing method, and a computer program that are excellent in backscattering.

  It is a further object of the present invention to provide excellent wireless communication capable of efficiently performing data transmission using reflected wave transmission from a data transmission apparatus holding data to a data processing apparatus for performing display output and other processing of data. A system, a data transmission device, a data transmission method, a data processing device, a data processing method, and a computer program are provided.

  A further object of the present invention is to efficiently transmit a plurality of files using reflected wave transmission from a data transmission apparatus having a reflector function to a data processing apparatus having a reflected wave reader function. Another object of the present invention is to provide a wireless communication system, a data transmission device and a data transmission method, a data processing device and a data processing method, and a computer program.

  It is a further object of the present invention to efficiently perform reflected wave transmission of a plurality of files while adjusting antenna directivity from a data transmission apparatus having a reflector function to a data processing apparatus having a reflected wave reader function. An excellent wireless communication system, data transmission apparatus and data transmission method, data processing apparatus and data processing method, and computer program are provided.

  The present invention has been made in consideration of the above-described problems, and is a wireless communication system that transmits one or more files from a data transmission apparatus to a data processing apparatus, and can be transmitted by the data transmission apparatus that is a data transmission source. A wireless communication system characterized by providing an interface capable of displaying a file on a data processing apparatus as a data transmission destination and selecting a transmission file. Here, the data transmission device modulates the reflected wave with respect to the received carrier according to transmission data and transmits the data, and the data processing device transmits the carrier wave and receives the reflected wave with respect to the carrier wave and demodulates the data, thereby Reflected wave transmission can be performed between the data transmission device and the data processing device.

  However, “system” here refers to a logical collection of a plurality of devices (or functional modules that realize specific functions), and each device or functional module is in a single housing. It does not matter whether or not.

  The wireless transmission system according to the present invention is intended to realize low power consumption in a communication mode in which a transmission ratio occupies most of communication between devices that are relatively limited to a short distance, Wireless transmission is performed using modulation of reflected waves based on the back scatter method used in RFID. The RFID system itself is widely known in the art as an example of a wireless communication means that can be applied only at an extremely short distance.

  Here, in the reflected wave transmission system, the unmodulated carrier transmitted from the reflected wave reader is attenuated before reaching the reflector. Further, the signal intensity decreases at the time of reflection, and the reflected wave is attenuated before reaching the reflected wave reader. Therefore, in order to obtain a reflected wave with sufficient reception intensity, at least one of the reflector and the reflected wave reader has antenna directivity, and a large antenna gain is obtained in a specific direction, thereby reducing the wireless transmission distance. In many cases, the device is stretched.

  In this case, however, the user needs to adjust the directivity of the reflector and the reflected wave reader each time a file is sent. For example, when it is desired to send several files, it takes a lot of trouble by repeating the operation of adjusting the directivity after sequentially specifying the files to be transferred.

  In the wireless communication system according to the present invention, a data transmission device serving as a data transmission source has a function of sending information on a file stored in a memory to a data processing device serving as a data transmission destination. In addition, by providing a function for selecting a transmission file on the display unit of the data processing device, an interface that allows the user to transmit a plurality of files while the directivity of the data transmission device is always directed to the data processing device. provide.

  Therefore, according to the present invention, when a number of files are transmitted from the data transmission apparatus to the data processing apparatus, it is possible to save time and effort required for adjusting the directivity of the data transmission apparatus each time the file is transmitted.

  According to the present invention, it is possible to efficiently transmit a plurality of files using reflected wave transmission from a data transmission device having a reflector function to a data processing device having a reflected wave reader function. A wireless communication system, a data transmission device and a data transmission method, a data processing device and a data processing method, and a computer program can be provided.

  In addition, according to the present invention, a plurality of files can be efficiently transmitted in a reflected wave while adjusting antenna directivity from a data transmission apparatus having a reflector function to a data processing apparatus having a reflected wave reader function. An excellent wireless communication system, data transmission apparatus and data transmission method, data processing apparatus and data processing method, and computer program can be provided.

  According to the present invention, a user selects and determines a file to be transmitted from an image transmission apparatus to an image display apparatus from a file list displayed on the image display apparatus (or a host device connected to the image display apparatus). can do. Therefore, when transmitting a number of files, it is not necessary to adjust the directivity of the image transmission apparatus each time each file is transmitted, and the operability is improved.

  Other objects, features, and advantages of the present invention will become apparent from more detailed description based on embodiments of the present invention described later and the accompanying drawings.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  The present invention is a communication mode in which the transmission ratio occupies most of the communication between devices that are relatively limited to a short distance. The purpose is to realize transmission and mutual communication, and wireless transmission is performed using a reflected wave based on the back scatter method used in RFID.

  The RFID system itself is widely known in the art as an example of wireless communication means that can be applied only locally. Examples of the communication method between the tag and the reader / writer include an electromagnetic coupling method, an electromagnetic induction method, and a radio wave communication method. The present invention relates to a radio wave communication system using a microwave such as a 2.4 GHz band.

  FIG. 1 shows a configuration example of a reflected wave transmission system according to an embodiment of the present invention.

  The host 1 includes an RF function unit 11, a host communication control function unit 12, and a host function unit 13. The RF function unit 11 operates as a reflected wave reader in the reflected wave transmission system.

  The host function unit 13 is configured by a host device that processes or reproduces and outputs received data, such as a stationary home appliance such as a television, a monitor, a printer, a PC, a VTR, and a DVD player.

  On the other hand, the terminal 2 includes an RF function unit 21, a terminal communication function control function unit 22, and a terminal function unit 23. The RF function unit 21 operates as a reflector in the reflected wave transmission system.

  The terminal function unit 23 includes a mobile terminal device that is a transmission data supply source, such as a digital camera, a video camera, a mobile phone, a portable information terminal, and a portable music player.

  Data transmitted from the host function unit 13 is modulated by the modulation function unit 121 of the host communication control function unit 12 via the control interface 14. The modulated signal 15 is transmitted to the terminal 2 on the unmodulated carrier 31 generated by the carrier generation source 111 of the RF function unit 11. In general, ASK is used for the downlink from the host 1 to the terminal 2 in consideration of the ease of detection on the terminal 2 side. The RF function unit 21 of the terminal 2 receives the unmodulated carrier 31 and obtains the demodulated signal 25. The demodulated signal 25 is demodulated by the demodulation function unit 223 and is received by the terminal function unit 23 via the control interface 24.

  Data transmitted by the terminal function unit 23 of the terminal 2 is modulated by the modulation function unit 222 of the communication control function unit 22. The modulated signal 26 is placed on the reflected wave 32 obtained by detecting the unmodulated carrier 31 in the RF function unit 26 and transmitted to the host 1. The RF function unit 11 of the host 1 receives the reflected wave 32 and obtains the demodulated signal 16. The demodulated signal 16 is demodulated by the demodulation function unit 123 and received by the host function unit 13 via the control interface 14.

  Further, in addition to the data transmission / reception function described above, the host 1 and the terminal 2 can be provided by providing the protocol function units (121, 221) that mutually function in the host 1 and the terminal 2 in the respective communication control function units (12, 22). Protocol control such as connection and disconnection is realized.

  In the reflected wave transmission system, it is possible to drive the system with low consumption that the RF function unit 21 of the terminal 2 does not need a carrier generation source. Further, by performing multi-level modulation on the terminal side, high-speed communication from the terminal to the host direction can be realized.

  The terminal 1 is, for example, a digital still camera or a digital video camera, and the host 2 is, for example, a television or a printer. It is assumed that a still image or a moving image is uploaded from the terminal 1 to the host 2 and displayed or printed out.

  In the uplink from the terminal 1 to the host 2, a low bit rate modulation scheme such as ASK or BPSK is common, but the gist of the present invention is not limited to this. When modulating the reflected wave, in addition to manipulating the load impedance such as the termination of the antenna, by giving a phase difference on the signal path along which the reflected wave reciprocates, multi-values with higher bit rates such as QPSK and 8-phase PSK modulation A modulation scheme can be realized. For example, Japanese Patent Application No. 2003-352223 already assigned to the present applicant discloses a back scatter type communication system incorporating QPSK modulation processing.

  On the other hand, the modulation in the host 1 uses ASK in consideration of the ease of detection on the terminal 2 side (described above). For this reason, the downlink from the host 1 to the terminal 2 has a low data rate, and the reflected wave transmission system has an asymmetric transmission line with different transmission rates for the uplink and the downlink.

  In a reflected wave transmission system, in general, in order to obtain a reflected wave with sufficient reception intensity, at least one of the reflector and the reflected wave reader has antenna directivity, and a large antenna gain is obtained in a specific direction. Thus, the wireless transmission distance is extended. In this case, every time a file is sent, the user needs to adjust the directivity of the reflector and the reflected wave reader. For example, when it is desired to send several files, it takes a lot of trouble by repeating the operation of adjusting the directivity after sequentially specifying the files to be transferred.

  Therefore, in the present embodiment, when a number of files are transmitted from the image transmission apparatus to the image display apparatus, the effort required to adjust the directivity of the image transmission apparatus is saved each time the file is transmitted. Specifically, the image transmission apparatus has a function of sending file information stored in a memory in the image transmission apparatus to the image display apparatus. By providing a function for selecting a transmission file on the display unit of the image display device, an interface is provided so that the user can transmit a plurality of files while the image transmission device is always directed to the image display device.

  FIG. 2 shows an example of a communication sequence for transmitting image data from an image transmission apparatus having a reflector function to an image display apparatus having a reflected wave reader function in the reflected wave transmission system according to the present embodiment. Show. Hereinafter, the communication sequence will be described with reference to FIG.

501: The user switches the image transmission apparatus to the data transmission mode from the operation / display unit of the image transmission apparatus.
502: The user switches the image display device to the data reception mode from the operation / display unit of the image display device.
503: The image display device starts continuous transmission of an unmodulated carrier.
504: The user orients the image transmission apparatus in the direction of the image display apparatus.
505: The user presses a transmission button from the operation / display unit of the image transmission apparatus.
506: The image transmission apparatus transmits a data transmission request packet to the image display apparatus.
507: Upon receiving the data transmission request packet, the image display apparatus stops continuous transmission of the unmodulated carrier.
508: If there is an error in the received data transmission request packet, the image display device generates a NACK and transmits it with ASK modulation. If there is no error and transmission is permitted. A transmission permission packet is generated and transmitted with ASK modulation.
509: When the transmission of the transmission permission packet is completed, the image display apparatus continuously transmits the unmodulated carrier again.
510: The image transmission apparatus transmits a file list packet to the image display apparatus.
511: When receiving the file list packet, the image display device stops continuous transmission of the unmodulated carrier.
512: The image display apparatus generates an ACK / NACK packet, transmits it with ASK modulation.
513: Upon completing the transmission of the ACK / NACK packet, the image display device continuously transmits the unmodulated carrier again.
514: The sequence of 510 to 513 is repeated until there is no file list data to be transmitted from the image transmission apparatus to the image display apparatus.
515: The image transmission apparatus completes transmission of the file list packet.
516: The image transmission apparatus transmits a file list transmission completion packet to the image display apparatus.
517: When receiving the file list transmission completion packet, the image display device stops continuous transmission of the unmodulated carrier.
518: The image display apparatus generates a NACK if there is an error in the received file list transmission completion packet, generates an ACK packet if there is no error, and transmits it with ASK modulation. If there is no error, the completed file list is displayed on the display unit.
519: When the image display apparatus completes the transmission of the ACK / NACK packet, it continuously transmits the unmodulated carrier again.
520: The user inputs a cursor key from the operation / display unit of the image transmission apparatus while looking at the display unit of the image display apparatus.
521: The image transmission apparatus transmits a cursor movement command packet to the image display apparatus.
522: Upon receiving the cursor movement command packet, the image display device stops continuous transmission of unmodulated carriers.
523: The image display apparatus generates a NACK if there is an error in the received cursor movement command packet, generates an ACK packet if there is no error, and transmits it with ASK modulation. The cursor position on the display unit is moved according to the command and displayed.
524: When the image display apparatus completes the transmission of the ACK / NACK packet, it continuously transmits the unmodulated carrier again.
525: The sequence of 520 to 524 is repeated until the user presses the enter button.
526: The user presses the enter button from the operation / display unit of the image transmission apparatus.
527: The image transmission apparatus transmits a determination command packet to the image display apparatus.
528: Upon receiving the determination command packet, the image display device stops continuous transmission of the unmodulated carrier.
529: The image display apparatus generates a NACK if there is an error in the received decision command packet, generates a transmission file request packet if there is no error, and transmits it with ASK modulation. In addition, the name of the file whose transmission is requested is displayed on the display unit.
530: When the transmission of the transmission file request packet is completed, the image display device continuously transmits the unmodulated carrier again.
531: Upon receiving the transmission file request packet, the image transmission apparatus reads the requested file from the memory.
532: The image transmission apparatus transmits a data packet.
533: When receiving the data packet, the image display device stops continuous transmission of the unmodulated carrier.
534: The image display apparatus generates a NACK if there is an error in the received data packet, generates an ACK packet if there is no error, and transmits it with ASK modulation.
535: When completing the transmission of the ACK / NACK packet, the image display device continuously transmits the unmodulated carrier again.
536: The sequence of 532 to 535 is repeated until there is no transmission data from the image transmission apparatus to the image display apparatus.
537: The image transmission apparatus completes the file transmission.
538: The image transmission apparatus transmits a file transmission completion packet to the image display apparatus.
539: Upon receiving the file transmission completion packet, the image display device stops continuous transmission of the unmodulated carrier.
540: The image display apparatus generates a NACK if there is an error in the received file transmission completion packet, generates an ACK packet if there is no error, and transmits it with ASK modulation. If there is no error, the completed file data is displayed on the display unit.
541: When the image display apparatus completes the transmission of the ACK / NACK packet, the image display apparatus continuously transmits the unmodulated carrier again.
542: The user presses a transmission button from the operation / display unit of the image transmission apparatus.
543: The image transmission apparatus transmits a data transmission request packet to the image display apparatus.
544: When receiving the data transmission request packet, the image display device stops the continuous transmission of the unmodulated carrier.
545: If there is an error in the received data transmission request packet, the image display apparatus generates a NACK and transmits it with ASK modulation. If there is no error in the packet and transmission is permitted, a transmission permission packet is generated and transmitted with ASK modulation. Then, the file list is displayed on the display unit.
546: When the image display apparatus completes the transmission of the transmission permission packet, the image display apparatus continuously transmits the non-modulated carrier again.
547: The user inputs a cursor key from the operation / display unit of the image transmission apparatus while looking at the display unit of the image display apparatus.
548: The image transmission apparatus transmits a cursor movement command packet to the image display apparatus.
549: Upon receiving the cursor movement command packet, the image display device stops continuous transmission of unmodulated carriers.
550: The image display device generates a NACK if there is an error in the received cursor movement command packet, generates an ACK packet if there is no error, and transmits it with ASK modulation. The cursor position on the display unit is moved according to the command and displayed.
551: When the image display apparatus completes the transmission of the ACK / NACK packet, it continuously transmits the unmodulated carrier again.
552: The sequence of 520 to 524 is repeated until the user presses the enter button.
553: The user presses the enter button from the operation / display unit of the image transmission apparatus.
554: The image transmission apparatus transmits a determination command packet to the image display apparatus.
555: When receiving the determination command packet, the image display device stops continuous transmission of the unmodulated carrier.
556: The image display apparatus generates a NACK if there is an error in the received decision command packet, generates a transmission file request packet if there is no error, and transmits it with ASK modulation. In addition, the name of the file whose transmission is requested is displayed on the display unit.
557: When the transmission of the transmission file request packet is completed, the image display device continuously transmits the unmodulated carrier again.
558: Upon receiving the transmission file request packet, the image transmission apparatus reads the requested file from the memory.
559: The image transmission apparatus transmits a data packet.
560: When receiving the data packet, the image display device stops continuous transmission of the unmodulated carrier.
561: The image display device generates a NACK if there is an error in the received data packet, generates an ACK packet if there is no error, and transmits it with ASK modulation.
562: When completing the transmission of the ACK / NACK packet, the image display device continuously transmits the unmodulated carrier again.
563: The sequence of 559 to 562 is repeated until there is no transmission data from the image transmission apparatus to the image display apparatus.

  The frame structures of the file list packet, cursor movement command packet, decision command packet, and file request command packet are shown in FIGS. 17 to 20, respectively.

  FIG. 3 schematically illustrates the hardware configuration of the image transmission apparatus. The illustrated image transmission apparatus 1200 corresponds to a device serving as a transmission source of image data, such as a digital camera or a camera-equipped mobile phone, and drives, for example, a battery (not shown) as a main power source.

  A single digital camera is composed of a camera unit 1202, a signal processing unit 1203, a memory card interface unit 1204, an operation / display unit 1205, and a USB interface unit 1206.

  The signal processing unit 1203 converts the image data input from the camera unit 1202 into image data of a predetermined format such as JPEG (Joint Photographic Experts Group), and the external memory card via the memory card interface unit 1204 1207 is stored.

  The operation display unit 1205 performs image display, various settings, and the like. The USB interface unit 1206 is used when an image is transferred to the PC using the USB interface.

  The wireless transmission module 1208 includes an antenna 1209, an antenna switch 1210, an antenna load 1211, a bandpass filter 1212, and an ASK detection unit 1213. In the present embodiment, the 2.4 GHz band is used as the frequency of the radio wave.

  When performing image transfer, when the wireless transmission module unit 1208 receives the image data read from the memory card 1207 by the signal processing unit 1203, the wireless transmission module unit 1208 uses the antenna switch 1210 connected to the antenna 1209 according to the bit image of the data. Performs on / off operation. For example, the antenna switch 1210 is turned on when the data is 1, and is turned off when the data is 0.

  As shown in the figure, when the antenna switch 1210 is on, the antenna 1209 is terminated with a 50Ω antenna load 1211. When the antenna switch 1210 is off, the antenna 1209 is open. This operation terminates when radio waves arrive from the transfer destination (described later) and reflects when the radio waves are off, so that the transfer destination detects image data by detecting the reflection of the transmission radio waves. Can be read. That is, the image data is basically transmitted as a reflected wave of a radio wave from the transfer destination caused by a change in the antenna load impedance accompanying the on / off operation of the antenna switch 1210.

  In the illustrated example, the reflected wave signal from the wireless transmission module 1208 is equivalent to an ASK modulated wave. However, the modulation method of the reflected wave signal is not limited to ASK modulation, and in addition to switching the antenna load impedance, PSK modulation may be performed by giving a phase difference on the reflected signal path of the received radio wave (described above). ).

  The antenna switch 1210 is generally composed of a gallium arsenide IC, and its power consumption is several tens of μW or less. Therefore, according to the communication method described above, wireless image transmission with ultra-low consumption can be realized.

  The bandpass filter 1212 and the ASK detection unit 1213 are used when receiving an ASK-modulated delivery confirmation signal from the transfer destination, but these two blocks are unnecessary if the transmission is a one-way transmission without confirming the delivery of the transmission. Become. On the other hand, when delivery confirmation is performed, the control is performed by the signal processing unit 1203.

  The bandpass filter 1212 is used for the purpose of passing a frequency of 2.4 GHz band and attenuating other frequency bands. The power consumption of the ASK detection unit 1213 necessary for confirming delivery can be realized with 30 mW or less.

  Therefore, the average power when transmitting image data in the image transmission apparatus 1200 shown in FIG. 3 can be 10 mW or less in the case of the delivery confirmation method, and the data transmission can be several tens of μW in the unidirectional transmission. This is an overwhelming performance difference compared to the average power consumption of a general wireless LAN.

  4 to 9 show the procedure of the processing operation in the signal processing unit 1203 of the image transmission apparatus 1200 in the form of flowcharts.

  FIG. 4 shows the processing operation under the data transmission mode. When the signal processing unit 1203 of the image transmission apparatus 1200 is switched to the data transmission mode by the user, the signal processing unit 1203 waits for a transmission button input of the operation / display unit 1205 (step S610).

  At this time, if a data transmission mode end request is received (step S680), the file list transmission history is deleted (step S690), and the data transmission mode is ended.

  When the transmission button is input (step S610), a data transmission request packet transmission sequence (step S620) is executed.

  Next, it is checked whether there is a file list transmission history (step 630). If there is no file list transmission history, a file list transmission sequence is executed (step S640), and then a user command transmission sequence is executed (step S650). If there is a file list transmission history, the user command transmission sequence is executed without executing the file list transmission sequence (step S650).

  When the signal processing unit 1203 of the image transmission apparatus 1200 completes the file transmission, it again waits for a transmission button input (step S610) and a data transmission mode end request (step S680) of the operation / display unit 1205.

  FIG. 5 shows a data transmission request packet transmission sequence in the image transmission apparatus 1200 in the form of a flowchart.

  When the data transmission request packet transmission sequence is started, a data transmission request packet is generated (step S621), transmitted (step S622), and then a transmission timer is started (step S623). This transmission timer is used to generate a transmission timing by timing out in a certain period.

  The signal processing unit 1203 of the image transmission device 1200 monitors a timeout of the transmission timer (step S624). When the timeout occurs, the CRC judgment result of the received packet is checked (step S625). If it is determined that there is no packet error, it is checked whether the received packet is NACK (step S626).

  If the received packet is NACK, the data transmission request packet is retransmitted (step S622). If the received packet is not a NACK, it is further checked whether it is a transmission permission packet (step S627). If the received packet is not a transmission permission packet, the signal processing unit 1203 of the image transmission apparatus 1200 ends the data transmission mode. If the received packet is a transmission permission packet, the signal processing unit 1203 of the image transmission apparatus 1200 completes the data transmission request transmission sequence.

  FIG. 6 shows a file list transmission sequence in the image transmission apparatus 1200 in the form of a flowchart.

  When the file list transmission sequence is started, the file information stored in the memory card 1207 is read through the memory card interface unit 1204 to create a file list (step S641). The file list includes file names stored in the memory, file sizes, update dates and the like.

  Next, a transmission packet is generated from the file list (step S642), and a packet transmission sequence is executed (step S643). Next, it is determined whether or not all file lists have been transmitted (step S644). If there is an untransmitted file list, packet generation (step S642) and packet transmission (step S643) are repeated.

  When transmission of the file list is completed, a file list transmission completion packet for notifying the image display apparatus of completion of transmission of the file list is generated (step S645), packet transmission is performed (step S646), and the file list is transmitted. A transmission history is created (step S647), and the file list transmission sequence is completed. The file list transmission history is information indicating whether or not the transmission of the file list is completed. For example, 1 is set when the transmission of the file list is completed, and 0 is set when the transmission of the file list is not completed.

  FIG. 7 shows a command transmission sequence in the image transmission apparatus 1200 in the form of a flowchart.

  When the command transmission sequence is started, the signal processing unit 1203 of the image transmission apparatus 1200 waits for input information of the operation / display unit 1205 (step S651).

  Upon receiving the cursor key input from the operation / display unit 1205 (step S652), the signal processing unit 1203 generates a cursor movement command packet (step S660), transmits the packet (step S661), and performs the operation / display again. It waits for input information of the display unit 1205 (step S651).

  When the signal processing unit 1203 receives a determination button input from the operation / display unit 1205 (step S653), the signal processing unit 1203 generates a determination command packet (step S654), transmits the generated packet (step S655), and starts a transmission timer. (Step S656).

  Next, the timeout of the transmission timer is monitored (step S657), and when the timeout occurs, the CRC determination result of the received packet is checked (step S658). Here, if there is a packet error, transmission is performed when the decision command packet is received (step S655). If it is determined that there is no packet error, it is further examined whether or not the received packet is a transmission file request packet (step S659). If the received packet is not a transmission file request packet, transmission is performed when the determination command packet is received (step S655). If the received packet is a transmission file request packet, the signal processing unit 1203 of the image transmission apparatus 1200 completes the command transmission sequence.

  FIG. 8 shows a file transmission sequence in the image transmission apparatus 1200 in the form of a flowchart.

  When the file transmission sequence is started, the file requested by the transmission file request packet received in the command transmission sequence is read from the memory card 1207 (step S671), a data packet is generated (step S672), and packet transmission is performed. A sequence is executed (step S673).

  Next, it is determined whether or not all the file data has been transmitted (step S674). If the file transmission has not been completed, data packet generation (step S672) and packet transmission (step S673) from the file data are performed. repeat.

  When the transmission of the file data is completed, a file transmission completion packet for notifying the image display device of the completion of the file transmission is generated (step S675), packet transmission is performed (step S676), and the file transmission sequence is completed.

  FIG. 9 shows a packet transmission sequence in the image transmission apparatus 1200 in the form of a flowchart. When the packet transmission sequence is started, the generated transmission packet is transmitted (step S691), and a transmission timer is started (step S692).

  Next, the timeout of the transmission timer is monitored (step S693), and when the timeout occurs, the CRC determination result of the received packet is checked (step S694). If it is determined that there is no packet error, it is further examined whether or not the received packet is ACK (step S695). If the received packet is not ACK, the packet is retransmitted (step S691). If the received packet is ACK, the packet transmission sequence is completed.

  FIG. 10 schematically shows a hardware configuration of the image display apparatus. An image display apparatus 1700 shown in the figure corresponds to an image reproduction apparatus such as a PC or a television that displays and outputs received image data, and a printer that prints out.

  In the present embodiment, since the image data is transmitted as a reflected wave, the wireless reception module 1700 has a reflected wave reader function, and transmits an unmodulated carrier for creating the reflected wave. The wireless reception module 1700 includes a 2.4 GHz band antenna 1701, a circulator 1702, a reception unit 1703, a transmission unit 1706, a frequency synthesizer 1709, a communication control unit 1710, and a host interface unit 411. Further, the reception unit 1703 is configured by a quadrature detection unit 1704 and an AGC amplifier 1705), and the transmission unit 1706 is configured by a mixer 1708 and a power amplifier 1707. A host interface unit 1711 is connected to a host device 1712 such as a PC, and transfers received image data.

  Transmission of an unmodulated carrier from the wireless reception module 1700 is realized by applying a certain DC voltage from the communication control unit 1710 to the mixer 1708. The frequency of the non-modulated carrier to be transmitted is determined by the frequency of the frequency synthesizer 1709 controlled by the communication control unit 1710. In the present embodiment, the 2.4 GHz band is used. The unmodulated carrier output from the mixer 1708 is amplified to a predetermined level by the power amplifier 1707 and transmitted from the antenna 1701 via the circulator 1702.

  The reflected wave from the image transmission device 1200 has the same frequency as that transmitted from the wireless reception module 1700 (described above). This reflected wave is received by the antenna 1701 and input to the receiving unit 1703 via the circulator 1702. Since the same local frequency as the transmission supplied from the frequency synthesizer 1709 is input to the quadrature detection unit 1704, an ASK modulated wave multiplied by the image transmission apparatus 1200 appears at the output of the quadrature detection unit 1704. . However, since the received signal has a phase different from that of the local signal, a modulation signal corresponding to the phase difference appears in the I-axis signal and the Q-axis signal.

  In the AGC amplifier unit 1705, the gain is controlled to the optimum value, and the output signal is passed to the communication control unit 1710. The communication control unit 1710 demodulates digital data from the I-axis and Q-axis signals, and correct data is transferred to the host device 1712 via the host interface unit 1711.

  When confirming the delivery of data from the image transmission apparatus 1200, the communication control unit 1710 receives an acknowledgment ACK (Acknowledgement) if the received packet data is correct, and a negative acknowledgment NACK (Negative Acknowledgement) if the received packet data is correct. The digital data is transferred to the mixer 1708 and subjected to ASK modulation. Whether the data is correct or not is determined by a CRC (Cyclic Redundancy Check) code added to the image data packet.

  FIGS. 11 to 14 show the procedure of processing operations in the communication control unit 1710 of the image display apparatus 1700 in the form of flowcharts.

  When the communication control unit 1710 of the image display device 1700 is switched to the data reception mode by the host device 1712 connected via the host interface unit 1711, the communication control unit 1710 starts continuous transmission of unmodulated carriers (step S1341). Waiting for a packet (step S1342).

  When the host device 1712 sends a data reception mode end request while waiting for a reception packet (step S1359), the transmission permission history (step S1360) and the file list reception history (step S1361) are deleted, and the data is deleted. Complete receive mode.

  The transmission permission history is information that holds a determination result as to whether or not to accept data from the image transmission apparatus. For example, if transmission permission is permitted during the data reception mode, 1 is set and must be permitted. 0 is set. Here, 0 is set to delete the transmission permission history. The file list history is information that holds whether or not reception of the file list from the image transmission apparatus has been completed. For example, reception of the file list may be completed during the data reception mode. 1 is set, and 0 is set if not completed. Here, it is set to 0 in order to delete the reception history of the file list.

  When receiving a packet while waiting for a received packet (step S1342), the communication control unit 1710 of the image display device 1700 performs CRC determination on the received packet (step S1343).

  If it is determined that there is an error in the received packet, a NACK packet is generated (step S1358), and a packet transmission sequence (step S1330) is executed.

  If it is determined that the received packet is correct, and if the received packet is a packet transmission request packet (step S1344), after executing the transmission permission determination sequence (step S1310), the packet transmission sequence is executed (step S1310). S1330).

  If the received packet is not a packet transmission request packet (step S1344), it is determined whether there is a transmission permission history (step S1345). If there is no history, a NACK packet is generated (step S1358) and transmitted (step S1330).

  If there is a transmission permission history, it is determined whether the received packet is a file list packet. If the received packet is a file list packet, a file list is created (step S1347), an ACK packet is generated (step S1357), and transmitted (step S1330).

  If the received packet is a file list transmission complete packet, the creation of the file list is terminated, a file list reception history is created (step S1349), and the file list and cursor are displayed on the display unit of the host device 1712. Is displayed (step S1350).

  FIG. 15 shows a display image of the file list. On the display screen 1800, a list of file information 1801 such as file name and size, update date and time is displayed, and a cursor 1802 is set at a default position.

  If the received packet is neither a file list packet nor a file list transmission completion packet and there is no file list reception history (step S1351), a NACK packet is generated (step S1358) and transmitted (step S1330). ).

  On the other hand, if there is a file list reception history, it is a user command packet (step S1352), a file data (step S1353), or a file transmission completion packet (step S1355). judge. If it is not any packet, a NACK packet is generated (step S1358) and transmitted (step S1330). If it is file data, the data of the host device 1712 is stored in the buffer (step S1354), an ACK packet is generated (step S1357), and transmitted (step S1330). If the received packet is a file transmission completion packet, the host device 1712 is notified of the completion of file reception, the file is displayed on the display unit of the host device 1712 (step S1356), and an ACK packet is generated. (Step S1357), a packet transmission sequence is executed (Step S1330). When the packet transmission sequence is completed, the process returns to reception waiting again (step S1342).

  FIG. 12 shows a transmission permission determination sequence in the image display apparatus 1700 in the form of a flowchart.

  When the transmission permission determination sequence is started, the communication control unit 1710 determines whether or not to permit data transmission from the image transmission apparatus. As the determination method, for example, permission / prohibition is determined based on whether the ID of the image transmission apparatus is a registration ID, or permission / prohibition is determined based on whether data transmission is accepted depending on the operation status of the host device 1712. A method such as a case is taken.

  If the data transmission from the image transmission apparatus is not permitted, the communication control unit 1710 deletes the permission history (step S1316), generates a transmission prohibition packet (step S1317), and ends the transmission permission determination sequence.

  Further, when permitting data transmission from the image transmission apparatus, the communication control unit 1710 checks whether there is a file list reception history (step S1312). If the file list reception history already exists and the file list is held, the file list is displayed on the display unit of the host device 1712 (step S1313), and a permission history is created (step S1314). If there is no file list reception history, the permission history is created without displaying the file list (step S1314). After creating the permission history, the communication control unit 1710 generates a transmission permission packet and ends the transmission permission determination sequence.

  FIG. 13 shows a user command processing sequence in the image display apparatus 1700 in the form of a flowchart.

  When the user command processing sequence is started, the communication control unit 1710 determines whether a cursor key movement command has been received (step S1321) or a decision command packet has been received (step S1324).

  If the received packet is a cursor / key movement command, the display of the cursor position displayed on the display unit of the host device 1712 is corrected according to the command information (step S1322), an ACK packet is generated (step S1323), The user command processing sequence is terminated. Reference numeral 1902 in FIG. 16 indicates a state in which the cursor display is moved down from the cursor position 1802 shown in FIG. 15 by the cursor position movement command.

  If the received packet is a decision command packet, a file transmission request packet for requesting transmission of the file indicated by the cursor displayed on the display unit of the host device 1712 is generated (step S1325), and the user command End the processing sequence. If the received packet is neither a cursor key movement command nor a decision command packet, communication control unit 1710 generates a NACK packet (step S1326).

  FIG. 14 shows a packet transmission sequence in the image display apparatus 1700 in the form of a flowchart.

  When the packet transmission sequence is started, the communication control unit 1710 stops transmission of the unmodulated carrier (step S1331). Next, the packet is transmitted (step S1332). When the transmission is completed, continuous transmission of the unmodulated carrier is started again (step S1333).

  The present invention has been described in detail above with reference to specific embodiments. However, it is obvious that those skilled in the art can make modifications and substitutions of the embodiment without departing from the gist of the present invention.

  In the present specification, the embodiment of the present invention has been described by taking as an example the transmission of an unmodulated carrier from the reading device side and the reflected wave transmission system that modulates the reflected wave with the transmission data on the transmission device side. The gist of the present invention is not limited to this. Even when a medium other than reflected wave transmission is used, the present invention is applied when a number of files are transmitted in a wireless or wired communication system that requires directivity adjustment between communication apparatuses. be able to.

  According to the present invention, when data transmission is performed via various media including a reflected wave transmission path, a file that can be transmitted in a data transmission device serving as a data transmission source is displayed in a data processing device serving as a data transmission destination. By providing an interface capable of selecting a transmission file, it is not necessary to sequentially adjust the directivity between communication devices each time a file is transmitted, and the operability is improved.

  In short, the present invention has been disclosed in the form of exemplification, and the description of the present specification should not be interpreted in a limited manner. In order to determine the gist of the present invention, the claims section described at the beginning should be considered.

FIG. 1 is a diagram showing a configuration example of a reflected wave transmission system according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of a communication sequence for transmitting image data between the image transmission apparatus and the image display apparatus in the reflected wave transmission system according to the present invention. FIG. 3 is a diagram schematically illustrating a hardware configuration of the image transmission apparatus. FIG. 4 is a flowchart showing a procedure of processing operations in the signal processing unit 1203 of the image transmission apparatus 1200. FIG. 5 is a flowchart showing a procedure of processing operations in the signal processing unit 1203 of the image transmission apparatus 1200. FIG. 6 is a flowchart showing a procedure of processing operations in the signal processing unit 1203 of the image transmission apparatus 1200. FIG. 7 is a flowchart showing a procedure of processing operations in the signal processing unit 1203 of the image transmission apparatus 1200. FIG. 8 is a flowchart showing a procedure of processing operations in the signal processing unit 1203 of the image transmission apparatus 1200. FIG. 9 is a flowchart showing a procedure of processing operations in the signal processing unit 1203 of the image transmission apparatus 1200. FIG. 10 is a diagram schematically illustrating a hardware configuration of the image display apparatus. FIG. 11 is a flowchart showing a procedure of processing operations in the communication control unit 1710 of the image display apparatus 1700. FIG. 12 is a flowchart showing a procedure of processing operations in the communication control unit 1710 of the image display apparatus 1700. FIG. 13 is a flowchart illustrating a procedure of processing operations in the communication control unit 1710 of the image display apparatus 1700. FIG. 14 is a flowchart showing a procedure of processing operations in the communication control unit 1710 of the image display apparatus 1700. FIG. 15 is a diagram showing a display image of the file list. FIG. 16 is a diagram showing a state in which the cursor display is moved down by one from the cursor position 1802 shown in FIG. 15 by the cursor position movement command. FIG. 17 is a diagram illustrating a frame configuration example of a file list packet. FIG. 18 is a diagram illustrating a frame configuration example of the cursor movement command packet. FIG. 19 is a diagram illustrating a frame configuration example of the determination command packet. FIG. 20 is a diagram showing a frame configuration example of a file request command packet. FIG. 21 is a diagram schematically illustrating a configuration example of the reflected wave transmission system. FIG. 22 illustrates a case where both the image transmission device and the image display device use omnidirectional antennas, and a directional antenna that allows both the image transmission device and the image display device to obtain a large gain in one direction. It is the figure showing the difference in the wireless communication distance when using FIG. 23 is a diagram illustrating an example in which the image transmission apparatus 301 using the directional antenna and the image display apparatus 302 are not facing each other. FIG. 24 is a diagram illustrating an example of a communication sequence of the reflected wave transmission system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1200 ... Image transmission apparatus 1202 ... Camera part 1203 ... Signal processing part 1204 ... Memory card interface part 1205 ... Operation / display part 1206 ... USB interface part 1207 ... Memory card 1208 ... Wireless transmission module 1209 ... Antenna 1210 ... Antenna 1210 Switch 1211 ... Antenna load 1212 ... Band pass filter 1213 ... ASK detector 1700 ... Wireless receiver module 1701 ... Antenna 1702 ... Circulator 1703 ... Receiver 1704 ... Quadrature detector 1705 ... AGC amplifier 1706 ... Transmitter 1707 ... Mixer 1708 ... Power amplifier 1709 ... Frequency synthesizer 1710 ... Communication control unit 1711 ... Host interface unit 1712 ... Host device

Claims (5)

A data transmission device that includes a user operation unit, modulates a reflected wave with respect to a received carrier wave according to transmission data, and transmits data; and a display screen that transmits the carrier wave and receives the reflected wave with respect to the carrier wave and demodulates the data A wireless communication system for transmitting one or more files by reflected wave transmission between devices,
The data transmission device transmits a file list relating to files that can be transmitted to the data processing device,
The data processing device displays the received file list on the screen,
The data transmission device transmits a user operation command for the display screen of the file list input via the user operation unit,
The data processing device changes the display content based on the received user operation command, and the data transmission device receives the user operation command for selecting a file to be transmitted from the file list. Request file transmission,
The data transmission device transmits the requested file to the data processing device;
A wireless communication system. A data transmission device for transmitting a file,
A user operation unit;
A communication means for modulating a reflected wave with respect to a carrier wave received from a data transmission destination according to transmission data,
With
The communication means transmits a file list relating to a transmittable file to the data transmission destination, and transmits a user operation command via the user operation means for the information of the transmittable file displayed at the data transmission destination. Sending the requested file to the data transmission destination in response to a file transmission request based on a user operation command from the data transmission destination.
A data transmission apparatus characterized by that. A data transmission method for transmitting a file in a data transmission device including a user operation unit and a communication unit that modulates a reflected wave with respect to a carrier wave received from a data transmission destination according to transmission data and transmits the data,
Sending a file list for transmittable files to the data destination;
Sending a user operation command to the data transmission destination via the user operation means for information on the transmittable file displayed at the data transmission destination;
Receiving a file transmission request based on a user operation command from the data transmission destination;
Sending the requested file to the data destination;
A data transmission method characterized by comprising: A data processing device that receives and processes a file from a data transmission source,
A display screen;
A communication means for transmitting a carrier wave and receiving a reflected wave to the carrier wave and demodulating data;
With
A file list relating to a transmittable file received from the data transmission source is displayed on the display screen, the display content is changed based on a user operation command received from the data transmission source, and the file A file transmission request is made to the data transmission source in response to receiving a user operation command for selecting a file to be transmitted in the list,
A data processing apparatus. A data processing method for receiving and processing a file from a data transmission source in a data processing apparatus having a display screen and a communication means for transmitting a carrier wave and receiving a reflected wave with respect to the carrier wave and demodulating data,
Receiving a file list of files that can be transmitted from the data source;
Displaying the received file list on the display screen;
Receiving a user operation command from the data source;
Changing display content based on the received user operation command;
Receiving a user operation command for selecting a file to be transmitted in the file list from the data source; and
Requesting file transmission to the data transmission source in response to the received user operation command;
A data processing method characterized by comprising:

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