KR20040073100A - Apparatus and method for transmitting packet in home network - Google Patents

Abstract

PURPOSE: An apparatus for transmitting packets in a home network, and a method therefor are provided to construct a home network at a low cost by executing data communication between a device for control and devices to be controlled by using a high-frequency signal. CONSTITUTION: A high-frequency transmitting and receiving unit transmits packets in high-frequency signals between a device(100) for control and devices(110) to be controlled. An electric field driving unit executes peculiar functions of the device(100) for control or devices(110) to be controlled. A control unit transmits packets with the device(100) for control or devices(110) to be controlled, and controls operations of the electric field driving unit.

Description

Apparatus and method for transmitting packet in home network

The present invention provides a packet in which various digital devices including a digital television receiver, a personal video recorder (PVR), a digital audio system, a digital video home system (DVHS), a refrigerator, a washing machine, or an air conditioner are loaded with predetermined data. The present invention relates to a home network for controlling an operation while transmitting, and more particularly, to a packet transmitter and a method for a home network for wirelessly transmitting a predetermined packet to each other using a low power high frequency signal of a specific frequency band.

The home network sets a digital device having a display screen as a control device, such as a digital television receiver, and a digital device such as a PVR, a digital audio system, a DVHS, a refrigerator, a washing machine, and an air conditioner that does not have a display screen. It is set as a controlled device, and the set control device and the controlled device transmit a packet containing predetermined data to each other so that the user can control the operation of the controlled device through the controlling device.

When the user makes an operation command of predetermined controlled devices through a control screen of a UI (User Interface) provided by the control device, the controlling device generates and transmits a predetermined packet including the operation command data of the user. The received control device receives the transmitted packet, performs an operation according to the operation command data in the packet, generates a packet of a response message according to the execution result of the operation command, and transmits the packet to the control device. After checking the operation state of the controlled devices by using the packet of the response message, the user is informed by displaying on the UI control screen.

In a conventional home network, a wired local area network (LAN), power line communication, digital subscriber line and its variations (cDSL), and a cable modem are provided so that the control device and the plurality of controlled devices can transmit predetermined packets to each other. Or a telephone modem or the like or a wireless LAN was used.

However, the use of the wired LAN, power line communication, xDSL, cable modem, or telephone modem requires a separate wiring to connect the devices to each other, which is very cumbersome and inconvenient, and of course, the control device and the device to be controlled. There were several problems, such as having to re-wire every time the location was changed.

And the use of the wireless LAN does not require a separate wiring work, while the installation location of the devices is free, while very expensive to give a lot of economic burden to the user, a strong electromagnetic wave of about 100 kHz or more occurs when transmitting packets There is a problem that a high possibility of the harm to the human body, the digital devices that have a low resistance to electromagnetic waves frequently malfunction due to the influence of electromagnetic waves.

It is therefore an object of the present invention to provide a packet transmission apparatus and method in a home network in which predetermined packets are wirelessly transmitted to each other using small output high frequency signals of a specific frequency band.

Another object of the present invention is to provide a packet transmission apparatus and method in a home network in which a predetermined packet is transmitted to each other by being installed regardless of a separate wiring work or arrangement position of devices.

In the home network of the present invention having the above object, the apparatus and method for transmitting a packet transmit devices a predetermined packet to each other using a small output high frequency signal of a specific frequency band. The small output high frequency signal of the specific frequency band uses, for example, a frequency applied to be arbitrarily used by the information communication unit, that is, a high frequency signal of 424.7xxx MHz band.

In the case of using the high frequency signal in the 424.7xxxMHz band, data can be transmitted and received within a distance of 1 km from the open site, and highly reliable data transmission and reception are possible within 100 m.

The present invention communicates by using the radio frequency signal of the 424.7xxxMHz band described above in accordance with the communication law user with a low power output of 10 없는, which does not require a separate report, and the cost is low in using a home network in the home. No additional wiring is required.

However, due to radio legal constraints, high-speed transmission of more than 1,200 to 2,400 bps is difficult, but it is suitable for home appliance control in homes or for applications that do not require simple or slightly complex but large data transfers.

In addition, in the case of applications using high frequency, there is a problem of communication disturbance such as interference or shadow area, but since the reliability is secured within a transmission distance of 100 m or less, the shadow area is not a problem in each home. You can minimize interference by avoiding collision when looking for channels.

In the home network of the present invention, a packet transmission device includes a control device and a plurality of controlled devices that control operations while wirelessly transmitting a predetermined packet to each other, and the control device and the plurality of controlled devices are predetermined A high frequency transmission / reception unit for wirelessly transmitting and receiving a packet as a high frequency signal, an electric field driver performing a unique function of the control device or the controlled device, the control device or the controlled device and a predetermined packet through the high frequency transmission / reception unit And a control unit for controlling the operation of the electric field driving unit, and the high frequency transmission / reception unit generates a PLL (Phase Locked Loop) for generating an oscillation signal of a predetermined frequency to modulate the packet under control of the control unit. Circuit and a packet provided by the controller The wireless communication module modulates the high frequency signal provided by the frequency conversion PLL circuit and demodulates the received packet to the control unit, and transmits the packet modulated by the wireless communication module through a transmission SAW filter and an antenna. A GMSK (Gaussian filtered Minimum Shift Keying) modem for receiving a packet through an antenna and a receiving SAW filter and inputting the packet to the wireless communication module is provided.

In the home network of the present invention, a packet transmission method transmits a connection request packet to another device to transmit data, and receives a packet containing the data when the connection request packet corresponding to the connection request packet is received from the other device. And transmits to a device, and generates and transmits a connectable packet when a connection request packet is received from another device, and generates and transmits a reception completed packet after receiving the data packet.

When the connectable packet is received, search for a channel to transmit data, inform the other device of the frequency of the searched channel, and modulate and transmit the packet carrying the data by modulating the frequency of the searched channel. Receives the frequency of the channel to be changed after receiving the received data packet at the received frequency and transmits the received complete packet, the channel search, characterized in that the search for the received signal strength indicator (Receiver Signal Strength Indicator: RSSI) It is done.

Also, the present invention repeatedly transmits the access request packet when a connectable packet is not received, determines whether a received packet is received after transmitting the packet containing the data, and when the received packet is not received. And repeatedly transmitting the packet carrying the data.

1 is a view showing the configuration of a home network according to the packet transmission apparatus of the present invention,

2 is a block diagram showing the configuration of a control device and a device to be controlled according to the packet transmission device of the present invention.

3 is a detailed block diagram showing the configuration of the high frequency transmission and reception unit of FIG.

4 is a view for explaining the bandwidth and occupied frequency bandwidth of each channel used in the packet transmission apparatus of the present invention,

5 is a view showing a data frame structure of a packet used in the packet transmission apparatus of the present invention.

FIG. 6 is a diagram illustrating data inserted into a data frame structure of a packet in the packet transmission apparatus of the present invention.

7 is a signal flow diagram showing an operation in the case of transmitting a packet in the packet transmission method of the present invention,

8 is a signal flow diagram illustrating an operation when receiving a packet in the packet transmission method of the present invention.

Explanation of symbols on the main parts of the drawings

100: control device 110: a plurality of devices to be controlled

200: high frequency transceiver 210: control unit

220: electric field drive unit 300: PLL circuit for frequency conversion

310: module for wireless communication 320: GMSK modem

330: SAW filter for transmission 340: Antenna

350: SAW filter for reception

Hereinafter, an apparatus and method for transmitting a packet in a home network of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view showing the configuration of a home network according to the packet transmission apparatus of the present invention. Here, reference numeral 100 denotes a control device such as a digital television receiver having a predetermined display screen, and reference numeral 110 denotes a plurality of controlled devices such as a DVD player, a PVR, a digital audio system, a DVHS, a refrigerator, a washing machine or an air conditioner.

The control device 100 and the plurality of controlled devices 110 mutually output a high frequency signal having a predetermined frequency, for example, a packet carrying predetermined data therebetween at a low power of about 10 kHz with a high frequency signal of 424.7xxx MHz band. Configured to transmit.

2 is a block diagram showing the configuration of a control device and a device to be controlled according to the packet transmission apparatus of the present invention. As shown therein, a high frequency transmission / reception unit 200 which transmits a predetermined packet as a high frequency signal having a predetermined frequency between the control device 100 and the controlled device 110, and the control device 100 or the device to be controlled. The electric field driver 210 performing the unique functions of the 110 and the high frequency transceiver 200 transmit the predetermined device and the control device 100 or the controlled device 110 to each other, The controller 220 controls the operation of the driver 210.

As shown in FIG. 3, the high frequency transmission / reception unit 200 generates a frequency locked phase locked loop (PLL) circuit 300 for generating an oscillation signal having a predetermined frequency to modulate the packet under the control of the control unit 220. And a wireless communication module for modulating a packet provided by the control unit 220 into a high frequency signal provided by the frequency conversion PLL circuit 300 and demodulating the received packet and inputting the received packet to the control unit 220. 310 and a packet modulated by the wireless communication module 310 through the transmission SAW filter 330 and the antenna 340, and transmits the packet through the antenna 340 and the reception SAW filter 350. It consists of a GMSK (Gaussian filtered Minimum Shift Keying) modem 320 to receive and input to the wireless communication module (310).

In the packet transmission apparatus of the present invention having such a configuration, when the controlling device 100 or the controlled device 110 transmits predetermined data, the control unit 220 generates a predetermined packet containing the data to be transmitted, The generated predetermined packet is input to the wireless communication module 310 of the high frequency transmission / reception unit 200. In addition, the controller 220 controls the PLL circuit 300 for frequency conversion to generate a high frequency signal of a predetermined frequency to modulate the packet, and to input the generated high frequency signal to the wireless communication module 310. .

Then, the wireless communication module 310 modulates a predetermined packet input from the controller 220 into a high frequency signal of a predetermined frequency generated by the frequency conversion PLL circuit 300, and modulates the predetermined packet into the high frequency signal. The packet is transmitted to the GMSK modem 320 and transmitted through the transmission SAW filter 330 and the antenna 340.

The high frequency signal transmitted as described above is sequentially received by the GMSK modem 320 through the antenna 340 and the receiving SAW filter 350 of the device 110 for control or the control device 100, and the module 310 for wireless communication. Will be entered.

Then, the wireless communication module 310 demodulates an input high frequency signal, extracts a predetermined packet, inputs the extracted predetermined packet to the controller 220, and the controller 220 is input from the wireless communication module 310. Decrypt the packet and perform a predetermined operation accordingly.

In the present invention, the frequency of the high-frequency signal is a specific low-power data communication frequency band that can be used without permission of the information communication department, that is, the frequency of 424.7xxxMHz band, the 424.7xxxMHz frequency band through the radio research institute. It is a band that can be commercialized through a series of certification test procedures.

When a predetermined packet is transmitted in the 424.7xxxMHz frequency band, as shown in FIG. 4, the occupied frequency bandwidth of each channel is 8.5 GHz, and the bandwidth of each channel is 12.5 GHz, 424.7000 MHz, 424.7125 MHz, and 424.7250. ㎒, 424.7375mhz, 424.7500mhz, 424.7625mhz, 424.7750mhz, 424.7875mhz, 424.8000mhz, 424.8125mhz, 424.8250mhz, 424.8375mhz, 424.8500mhz, 424.8625mhz, 424.8750mhz, 424.8875mhz, 424.9000mhz, 424.9125mhz, 424.9250mhz, It can have a total of 21 channels at 424.9375 MHz and 424.9500 MHz.

In addition, a frequency shift keying (FSK) modulation method by the GMSK modem 320 is used as a data transmission method between the control device 100 and the plurality of controlled devices 110, and at the same time, predetermined packets are exchanged with each other. It uses a packet switched method.

Here, the FSK method is a simple frequency modulation technique that combines binary data into one carrier and generates only two changes of '0' and '1' within a predetermined frequency band, and is about 1200bps (bits per second) in a low speed asynchronous manner. Data can be transmitted at a speed of about.

Both the control device 100 and the controlled device 110 are bidirectional communication that transmits and receive each other by using the high frequency transceiver 200, and has a switching time of about 40 ms, and transmits and receives a predetermined packet. In this case, it has a transmission / reception pause time of about 40ms.

In addition, the protocol for communication between the control device 100 and the device to be controlled 110 is basically the same, and the unique codes assigned to the devices 100 are different from each other. The unique code is provided with, for example, a separate dip switch or the like in the controller 220, or is automatically set to distinguish the devices 100 and 110.

In the packet switching scheme, when data is transmitted, data is decomposed and transmitted in a basic transmission unit called a packet, and then reassembled and processed into original data. The data frame structure of the packet used in the present invention is shown in FIG. As shown in FIG. 5, a 5-byte start preamble signal indicating the start of a packet for stabilization of a packet transmitted wirelessly, and a 1-byte sender capable of identifying the devices 100 and 110 transmitting the packet. A unique byte, a unique byte unique to the receiver for identifying the device (100, 110) that will receive the packet, and a unique byte for the subscriber identification code for distinguishing the home network from interference with other home networks; 1 byte instruction to indicate the type of data to be transmitted, 32 bytes of data, and CR for checking the checksum Cyclic redundancy checking (C) and a 5-byte end preamble signal for notifying the end of the packet are sequentially provided.

The controller 220 of the devices 100 and 110 receiving the packet having such a configuration compares the receiver unique code in the packet with the device unique code preassigned to itself, and compares the receiver unique code in the packet with the receiver unique code. If the assigned device unique codes do not match, the data in the packet is regarded as unnecessary data. When the receiver unique code in the packet and the device unique code assigned to the same match, the controller 220 extracts and analyzes the data in the packet, and performs a predetermined operation according to the analyzed data.

Data inserted in the data frame structure of the packet is as shown in FIG. 6, for example. That is, the start and end preamble signals are set to 'AAAAA' as '1' and '0' alternately consecutive so that the devices 100 and 110 receiving the packets can be easily synchronized. The unique code is set to, for example, '0' to the control device 100, and one of '20 to 100 'is selectively given to the controlled device 110, and the rest is reserved. The 100 and the controlled device 110 use the assigned unique code when communicating. The subscriber identification code is settable by the user and used to protect his home network from other home networks. For example, the subscriber identification code is set to '0x00' as a default value. The command is, for example, '1' when transmitting or receiving data, '2' when transmitting or receiving a request, and '3' when transmitting or receiving an acknowledgment (ACK). Set to '4' to send and receive messages. Data is based on 32 bytes, and its size can be changed according to the type of instruction. The CRC is obtained by setting a CRC corresponding to bytes from the sender unique code to the data.

7 is a signal flow diagram showing an operation in the case of transmitting a packet in the packet transmission method of the present invention. As shown in FIG. 2, the controller 220 determines whether data should be transmitted to the other devices 100 and 110 in step 700. That is, the controller 220 determines whether there is predetermined data to be transmitted and the data to be transmitted. If there is, in step 702 generates a connection request packet for requesting a communication connection with the other device (100, 110) and transmits the frequency of the basic channel through the high-frequency transceiver 200.

That is, in the present invention, one channel among the 21 channels as described above, for example, 424.7000 MHz is set in advance as a basic channel, and the control unit 220 controls the frequency conversion PLL circuit of the high frequency transmission / reception unit 200. The control unit 300 generates the frequency of the basic channel and inputs the connection request packet to the wireless communication module 310 so that the wireless communication module 310 sends the connection request packet to the frequency conversion PLL circuit. Modulated by the frequency of the basic channel generated by the 300, the modulated packet transmits the GMSK modem 320, the transmission SAW filter 330 and the antenna 340 sequentially.

In the next step 704, the control unit 220 waits for reception at the frequency of the basic channel for a set time, and then in step 706 notifying that it is possible to access from other devices (100, 110) receiving the connection request packet. It is determined whether the connectable packet is received, and if the connectable packet is not received, the process returns to step 702 and generates and transmits a connection request packet.

When the connectable packet is received in step 706, the controller 220 searches for a channel through which communication is possible in step 708. That is, the controller 220 searches for a receiver signal strength indicator (RSSI) of each channel to set one channel that can most accurately transmit a predetermined packet without being lost, and in step 710 A packet including the frequency of the set channel is generated and transmitted to the corresponding devices 100 and 110.

In the next step 712, the control unit 220 switches to the frequency of the channel, that is, controls the PLL circuit 300 for frequency conversion to generate the frequency of the channel to transmit the data, and in step 714 Generate a packet of data to be transmitted to 100 and 110, and transmits the generated data packet to the wireless communication module 310 in step 716, and then informs the reception of the packet of the transmitted data in step 718. It is determined whether the received packet is received from the corresponding device (100, 110), and if the received packet is not received, repeats the operation of returning to step 712 and transmitting the data packet, and receiving the received packet. When is received, it returns to the initial state.

8 is a signal flow diagram illustrating an operation when receiving a packet in the packet transmission method of the present invention. As shown in FIG. 2, the controller 220 determines whether a connection request packet is received by the wireless communication module 310 through the antenna 340, the reception SAW filter 350, and the GMSK modem 320 in step 800. If it is determined that the connectable request packet is received, the controller 220 generates a connectable packet indicating that the connection is accessible in step 802, and the accessibility packet generated in step 804 is a basic channel. Transmit at the frequency of.

After transmitting the connectable packet as described above, in step 806, it is determined whether a packet indicating a change frequency to transmit data is received, and when the change frequency packet is received, the controller 220 determines in step 808 Change the reception frequency to the change frequency in the changed frequency packet at step 810, and then wait for reception for a predetermined time in step 810, and whether the data packet is received from the other device 100 or 110 at step 812. Judge.

If no data is received in step 812, 1 is added to the number of waiting times for reception N in step 814, and the number of waiting times for reception N for step 816 is four or more times, for example. If it is determined that the acknowledgment is not 4 or more, the process returns to step 810 and waits for reception, and repeats the operation of determining whether the data packet is received.

When the data packet is received in step 812, the control unit 220 changes the transmission frequency to the change frequency of the changed frequency packet received in step 806 in step 818, and in step 820. A reception completion packet for notifying reception of data is generated and transmitted, and in operation 822, a predetermined operation is performed according to the data of the received data packet.

On the other hand, while the present invention has been shown and described with respect to specific preferred embodiments, various modifications and changes of the present invention without departing from the spirit or field of the invention provided by the claims below It can be easily understood by those skilled in the art.

As described above, according to the present invention, a control network and a plurality of controlled devices perform data communication with each other by using a specific low power high frequency signal of 424.xxxxMHz, so that a home network can be configured at a low cost. The installation work is very simple since there is no need for wiring work and the like, and the devices can be moved and installed at an arbitrary position.

Claims (7)

A packet transmission apparatus of a home network having a control unit for generating a predetermined packet and controlling an operation of the electric field driver according to the input packet, and a high frequency transmission / reception unit for transmitting the packet generated by the control unit and inputting the received packet to the control unit. To The high frequency transceiver; A frequency locked phase locked loop (PLL) circuit for generating an oscillation signal of a predetermined frequency to modulate the packet under control of the controller; A wireless communication module for modulating a packet provided by the controller into a high frequency signal provided by the PLL circuit for frequency conversion and demodulating the received packet and inputting the received packet to the controller; And Packet transmission apparatus of a home network comprising a GMSK (Gaussian filtered Minimum Shift Keying) modem for transmitting a packet modulated by the wireless communication module through an antenna and input the packet received through the antenna to the wireless communication module. . 2. The apparatus of claim 1, further comprising: between the GMSK modem and an antenna; And a transmission SAW filter and a reception SAW filter for filtering packets to be transmitted and received. A first step of transmitting, by the first device, a connection request packet to the second device; A second step of generating a connectable packet after the second device receives the connection request packet of the first step and transmitting it to the first device; A third step of generating a data packet containing predetermined data after the first device receives the connectable packet of the second step and transmitting the generated packet to the second device; A fourth step of generating, by the second device, the received packet and transmitting the received packet to the first device after receiving the data packet transmitted in the third step; And And a fifth process of receiving, by the first device, the reception completion packet of the fourth process to confirm transmission of the data packet. The method of claim 3, wherein The third process is; Search for a channel to transmit data when the connectable packet is received, transmit the frequency of the retrieved channel to the second device, and then modulate and transmit the frequency of the retrieved channel; The fourth process is; Receiving a frequency of the searched channel, receiving a data packet at a frequency of the received channel, and then transmitting a received packet. 5. The apparatus of claim 4, wherein the channel search comprises; A packet transmission method of a home network, characterized by searching by a receiver signal strength indicator (RSSI). The method of claim 3, wherein the first process comprises; And repeating transmission of the access request packet when a connectable packet is not received in the second process. The method of claim 3, wherein the fifth process comprises: And repeating transmission of the data packet of the third process when the reception complete packet is not received.