WO2003005599A1

WO2003005599A1 - Power line communication apparatus using spread spectrum and automatic meter reading system comprising with power line communication apparatus

Info

Publication number: WO2003005599A1
Application number: PCT/KR2001/001907
Authority: WO
Inventors: Hee-Yeoun Jeoun; Joo-Heon Cha; Keun-Young Kim
Original assignee: Naeil Community Co., Ltd.
Priority date: 2001-07-04
Filing date: 2001-11-09
Publication date: 2003-01-16

Abstract

The present invention relates to a power line communication (PLC) device using the spread spectrum applicable to the AMR system, HA, FA and building automation system. The PLC device includes power line transformer, matching filter, spread spectrum signal generator, control device and external interface. The PLC device can decrease the data transmission error, can be applied to various peripheral devices without exchanging a new power line communication device, can provide a more stable and faster data communication, can minimize the signal attenuation on the power line, can enable long communication, and can enhance the security in the power line communication.

Description

POWER LINE COMMUNICAΗON APPARATUS USING SPREAD SPECTRUM

AND AUTOMATIC METER READING SYSTEM COMPRISING WITH POWER

LINE COMMUNICATION APPARATUS

Technical Field

The present invention relates to a power line communication apparatus and

automatic meter reading system utilizing the power line communication.

Background Art

In general, power line communication (PLC) is a data communication method

that functions by carrying a carrier on the commercial AC (alternating current) signal

through power lines. The communication line can be any power line installed at a

home, office or factory.

The PLC has been applied to AMR (automatic meter reading), HA (home

automation), building automation, FA (factory automation), etc.

Presently, the AMR systems can monitor water supply, manufactured gas supply

and electricity supply through Internet based web application.

Users are able to remotely watch and control lighting at home, internet

information device, manufactured gas, sensors for fire detection and security, security

devices such as CCD cameras, HVACs (heating, ventilation and air conditioning) such as air conditioners, and audio/video devices (hereinafter these devices are referred to as

HA peripherals), by means of personnel computers, mobile phones, and PDAs etc.

Presently, home automation servers integrate information generated from HA

peripherals at home, process the information, and manages the information.

This is presently accomplished by using various wired or unwired

communication methods such as HomePNA (Home Phone line Networking Alliance),

RF (Radio Frequency), or PLC, etc.

Building automation systems use PLC communication to remotely monitor the

running status of the elevators in buildings and the illumination status of each floor of

buildings.

Factory automation systems uses PLC communication to remotely control

numerical control-type machine tools used for the automation of assembly lines,

industrial robots and various sensors, etc (hereinafter these devices are referred to as HA

peripherals).

The following are conventional arts: such as K.R. Patent No. 0060984 (title of

invention: "Data Communication Circuit and Method of Power line Transmitting

module"), and K.R. Patent. Publication No. 1999-069965 (title of invention: "Automatic

Meter Reading Method and System Using a Power line").

K.R. Patent No. 0060984 describes a power line transmitting module circuit.

Particularly it describes the data communication circuit of a power line transmitting module which is able to perform two-way data communication wherein the two-way

data communication generates synchronous signals by using commercial AC power and

then determines the length of time elapsed while transmitting and receiving data by

using the synchronous signal.

K.R. Patent No. 0060984 comprises a first microcomputer, a PLC modem, a

second microcomputer, an ADC/DAC, a phase detector, and a buffer.

K.R. Patent Publication No. 1999-069965 describes an automatic meter reading

method and system that uses a power line in order to take distance telemeter

measurements using already installed power lines as its communication medium.

K.R. Patent Publication No. 1999-069965 comprises a meter, a first data-

collecting device, and a second data-collecting device.

A conventional power line communication device, such as those in K.R. Patent

No. 0060984 and the K.R. Patent Publication No. 1999-069965, used for the purpose of

data communication by via conventional power lines have the drawback of being

susceptible to noise from the power lines.

A narrow band frequency with a single carrier frequency is used in power line

communication. Consequently, transmission errors occur, if the fixed single carrier

frequency is affected by power line noise, making the transmission of the metering data

unstable.

Also, power line communication devices need to provide various communication methods, communication protocols and various interfaces in order to be

applied to various peripheral devices, because there are varieties of peripheral devices

used for HA and FA.

Particularly, it is not advantageous, from a cost and device utilization viewpoint,

to replace devices and add new interfaces to a changed peripheral device every time a

peripheral device changes.

Disclosure of the Invention

Therefore, the present invention is intended to overcome the above-mentioned

disadvantages, and it is an object of the present invention to provide a power line

communication apparatus able to reduce the error rates of data transmission when a

predetermined carrier frequency is effected by noises from a power line, and an AMR

system to operate in conjunction with the power line communication apparatus.

It is another object of the present invention to provide a power line

communication apparatus, which enables fast and stable data communication via power

lines, and an AMR system that operates in conjunction with the power line

communication apparatus.

It is still another object of the present invention to provide a power line

communication apparatus, which provides improved security for prevention intentional

leakage of data being transmitted when using a single carrier frequency, and an AMR system that operates in conjunction with the power line communication apparatus.

It is still another object of the present invention to provide a power line

communication apparatus, that enables long distance transmissions by minimizing

signal attenuation, and an AMR system that operates in conjunction with the power line

communication apparatus.

It is still another object of the present invention to provide a multi-mode power

line communication apparatus, which can be used in master mode or slave mode as

selected and configured by the user.

It is still another object of the present invention to provide a power line

communication apparatus, which is applicable to various peripheral devices; thereby

circumventing the need to replace the peripheral devices with a new power line

communication devices when a need for different peripheral devices arises, and an

AMR system that operates in conjunction with the power line communication apparatus.

. It is still another object of the present invention to provide a power line

communication apparatus, which provides various interfaces operational with not only

an AMR but also HA, FA and building automation systems, and an AMR system that

operates in conjunction with the power line communication apparatus.

Brief Description of the Drawings

FIG. 1 is a rough block diagram of the AMR system using spread spectrum, which is applied to telemetering in accordance with one preferred embodiment of the

present invention.

FIG. 2 is a rough block diagram of the AMR system using spread spectrum,

which is applied to telemetering, HA and FA in accordance with one preferred

embodiment of the present invention.

FIG. 3 is a block diagram of the power line communication device using spread

spectrum in accordance with another preferred embodiment of the present invention.

FIG. 4 is a block diagram of a transceiver in the power line communication

device using spread spectrum in accordance with another preferred embodiment of the

present invention.

FIG. 5 is a flow chart illustrating the communication initializing method for

power line communication between the master mode power line communication device

and the slave mode power line communication device using spread spectrum in

accordance with one preferred embodiment of the present invention.

FIG. 6 is a flow chart illustrating the communication initializing method for

and the slave mode power line communication device using spread spectrum in

accordance with another preferred embodiment of the present invention.

FIG. 7 is a flow chart illustrating the power line communication method,

executed by the master mode power line communication device using spread spectrum, together with the slave mode power line communication device in accordance with one

preferred embodiment of the present invention

FIG. 8 is a flow chart illustrating the power line communication method,

executed by the slave mode power line communication device using spread spectrum,

together with the master mode power line communication device in accordance with

one preferred embodiment of the present invention.

FIG. 9 is an illustration of the structure of a packet to which the OSI 7 layer is

applied in the power line communication transmission using spread spectrum in

accordance with one preferred embodiment of the present invention.

FIG. 10a is an illustration of the structure of a packet that has been transmitted

from a master mode power line communication device using spread spectrum to the

slave mode power line communication device in accordance with one preferred

embodiment of the present invention.

FIG. 10b is an illustration of the structure of a packet that has been transmitted

from a slave mode power line communication device using spread spectrum to a

peripheral device in accordance with one preferred embodiment of the present invention.

FIG. 10c is an illustration of the structure of a packet that has been transmitted

from a peripheral device to the slave mode power line communication device using

spread spectrum in accordance with one preferred embodiment of the present invention.

FIG. 11-13 is a rough block diagram of the AMR system using spread spectrum, having power line communication devices using spread spectrum in accordance with

one preferred embodiment of the present invention.

FIG. 14 and 15 are rough block diagrams of a system wherein a power line

communication device using spread spectrum is applied to an HA in accordance with

one preferred embodiment of the present invention.

FIG. 16 and 17 are rough block diagrams of a system wherein a power line

communication device using spread spectrum is applied to an FA in accordance with

one preferred embodiment of the present invention.

FIG. 18 is a flow chart illustrating the remote meter reading process executed

within the AMR system in accordance with one preferred embodiment of the present

invention

FIGS. 19 shows a window used to display the results, provided by the manager

server in the AMR system, of the remote meter reading process.

Best Modes for carrying out the Invention

Hereinafter, preferred embodiments of the present invention will be described in

more detail with reference to the accompanying drawings, but it is understood that the

present invention should not be limited to the following embodiments.

FIG. 1 is a rough block diagram of the AMR system using spread spectrum that is applied to telemetering in accordance with one preferred embodiment of the present

invention.

Referring to FIG. 1, the AMR system comprises a plurality of slave mode

power line communication devices 100 using spread spectrum, a plurality of meters

104-1, ..., 104-N (hereinafter referred to as 104), objects of metering 102-1, ...,102-N

(hereinafter referred to as 102), a master mode power line communication device 110

coupled to a slave mode power line communication device 100 through a power line, a

manager server 140 coupled to the master mode power line communication device 110

by way of a gateway and a modem connected through a leased line for data

communication, a measurement database 150, a personal computer (PC) 160 coupled to

the manager server 140 through wired and/or unwired network, a PCS (Personal

Communication Systems) 162.

When the manager server 140 requests meter-reading data from the master

mode power line communication device 110, the request for sending meter-reading data

is transmitted to the meter 104 by way of the slave mode power line communication

device 100. The meter-reading data is then transmitted to the manager server 140 by

way of the meter 104, the slave mode power line communication device 100, and the

master mode power line communication device 110.

The manager server 140 collects meter-reading data from a plurality of meters

104, takes the statistics of the meter-reading data, displays the total usage for day, week, or month to the users through the wired or unwired Internet.

FIG. 2 is a rough block diagram of the AMR system using spread spectrum that

is applied to telemetering, HA and FA in accordance with one preferred embodiment of

the present invention. Hereinafter, illustrated primarily as the differences by FIG 1.

Referring to FIG. 2, the FIG.2 differs with FIG. 1 in that the slave mode power

line communication device 100 is able to be additionally coupled to the HA's peripheral

device 105-1, ... , 105-N (hereinafter referred to as 105), the HA' controller 106-1, ... ,

106-N (hereinafter referred to as 106), the FA' peripheral device 107-1, ..., 107-N

(hereinafter referred to as 107), and the FA' controller 108-1, ..., 108-N (hereinafter

referred to as 108).

The slave mode power line communication device 100 receives status data about

the HA's peripheral device 105 and the FA's peripheral device 107 from the HA's

controller 106 and the FA's controller 108, transforms the status data into spread

spectrum signal, puts the spread spectrum signal onto a power line (hereinafter, the

spread spectrum signal on the power line is referred to as the spread spectrum power

line signal), and transmits the spread spectrum power line signal to the master mode

power line communication device 110.

The master mode power line communication device 110 receives the spread

spectrum power line signal, transforms the phase of the spread spectrum power line

signal into 0 or 1 bit data, and transmits the data to the gateway 120. The detailed descriptions about the slave mode power line communication device 100 and the master

mode power line communication device 110 will be illustrated later. The gateway 120

transmits data packets to the manager server 140 by way of a modem 130 although it is

not drawn in FIG. 2. The manager server 140 receives the data packets, and then

processes, and utilizes the packet data in an AMR, HA and FA.

FIG. 3 is a block diagram of the power line communication device using spread

Referring to FIG. 3, the power line communication devices 100, and 110 using

spread spectrum comprises a power line transformer (or PL transformer 320, transceiver

300 coupled to the PL transformer 320, a control device 330 coupled to the transceiver

300 through buses, a storage device 350 coupled to the control device 330 through

buses, an external interface 340 coupled to the transceiver 300, the control device 330

and the storage device 350 coupled through buses.

The power line communication device 100, and 110 is able to selectively operate

in master mode or slave mode. These modes can be set by a hardware method such as

a dip switch switchover. When the master mode or the slave mode is set by dip switch,

the mode bit is set 0 to or 1, and transmitted to the controller device 330 through the

buses of the power line communication device 100, 110. The controller device 330

then recognizes the master mode or slave mode. Also, the mode can be set by a

software method. The controller device 330 is able to interpret a mode setting command that is transmitted to the power line communication device 100, 110 via

packet data. The operation of each mode is illustrated later.

The PL transformer 320 receives the spread spectrum power line signal,

transforms and clamps the spread spectrum power line signal into a spread spectrum

data signal, and transmits the spread spectrum data signal to the transceiver 300. Here,

the spread spectrum power line signal is the signal that includes packet data signals

carried on a carrier varying within a predetermined frequency range through a spread

spectrum processing and the signal transmitted on the power line transmitted. The

spread spectrum processing will be illustrated later. Also, the PL transformer 320

receives the spread spectrum data signal from the transceiver 300, and transforms and

then puts the spread spectrum data signal onto the power lines. Here, the spread

spectrum data signal is generated from the spread spectrum signal generator 310 of the

transceiver 300.

The transceiver 300 receives and amplifies the output of the PL transformer 320,

transforms the output from analogue to digital, generates encoded binary data 0s and Is,

checks CRC errors, and transmits the results to the controller device 330 through a data

bus.

Also, the transceiver 300 receives packet data at the physical layer from the data

bus, generates a spread spectrum data signal, produces the spread spectrum power line

signal, which is transformed by the PL transformer 320, and put onto the power line. The controller device 330 receives data from the meter 104 etc, generates packet

data at the network layer and the data link layer (in reference to FIG. 9), and transmits

the packet data to the transceiver 300 through the data bus.

Also, the controller device 330 receives packet data at the physical layer, which

is received from the power line and is transmitted from the data bus by way of the

transceiver 300, confirms the serial number of the power line communication device

that is transmitting the packet data by using the received packet data at the application

layer which is transformed from the data link layer through the network layer. The

controller device 330 casts away the received packet when the received serial number

coincides with the serial number of its own power line communication device. When

the serial number coincides, the controller device 330 analyzes the received packet data,

interprets the received command, and executes a series of operations according to the

results of the interpretation.

Also, the controller device 330 checks for errors in the received packet data by

using error checks algorithms such as a CRC algorithm etc. Also, the controller device

330 controls the transmitting of data to the bus and the receiving of data from the bus.

The storage device 350 stores the meter-reading data extracted from the received

packet data, the status data about various peripheral devices (hereinafter referred to as

slave application resource information), and the program used to execute operations

performed in the controller device 330. The slave mode power line communication device 100 transmits the slave application resource information to the master mode

power line communication device 110, and information about changed peripheral

devices can be automatically loaded whenever a peripheral device changes. The slave

mode power line communication device 100 loads the application program used to

control the changed peripheral devices into the controller device 330, and the controller

device 330 is able to control the changed peripheral device by means of having the

application program use the slave application resource information.

The external interface 340 causes the power line communication device coupled

to various peripheral devices. The external interface 340 can use RS-232C, SPI

(Serial-Parallel Interface), I2C, and CAN (Control Area Network) interface etc. to

interface with the meter, the HA's controller 105 and the FA's controller 108.

FIG. 4 is a block diagram of a transceiver in the power line communication

present invention.

Referring to FIG. 4, the transceiver 300 comprises an amplifying and

transforming device 302, a matching filter 304 coupled to the amplifying and

transforming device 302, a spread spectrum signal generator 310 coupled to the

matching filter 304, a CRC circuit coupled to the matching filter 304 and to the spread

spectrum signal generator 310, a clock generator 312 coupled to the matching filter 304,

to the spread spectrum signal generator 310 and to the CRC circuit 306, a spread spectrum encoding template storage device 314 coupled to the matching filter 304, to

the spread spectrum signal generator 310 and to the clock generator 312.

The amplifying and transforming device 302 comprises an amplifier and an

ADC (analogue to digital converter), and amplifies the signal generated by the PL

transformer 320, and produces digitalized spread spectrum data that is transformed into

digital signals of 0 or 1.

The matching filter 304 calculates the correlation between the digitalized spread

spectrum data and the internal template that previously stored the encoded value of the

positive phase and the inverse phase of the spread spectrum power line signal. Namely

the matching filter 304 calculates the correlation value. After the calculation of the

correlation, the digitalized spread spectrum data is transformed into binary data encoded

to correspond to the phase of the waveform of the spread spectrum data signal.

Namely, the matching filter 304 is a digital filter which calculates the correlation

between the received signal (the digitalized spread spectrum data) and the internal

template which has previously encoded the value of the positive phase and the inverse

phase of the lOOus interval spread spectrum power line signal. Each point of the

spread spectrum power line signal with a positive or inverse phase is converted into

binary values and stored in the spread spectrum encoding template storage device 314.

Here, the spread spectrum encoding template storage device 314 can utilize ROM, and

EEPROM etc for its storage mechanism. Here, the amplitude of the correlation value distinguishes the data of the received signal, and the status of the correlation is

determined by the phase (positive or inverse) of the received signal. The modulation

period of each data bit is compressed so that the signal transmitted over the power line

(the spread spectrum power line signal) can be rapidly transmitted. Corresponding to

the modulation period, the length of time elapsed while filtering one of the received

signals in de-modulation process is the same as the modulation period (for example less

than 1ms). The output of the matching filter is matched with the waveform of the

received signal, transmitted to the controller device 330 by means of the internal

interface 308, and is transformed into a frame at the data link layer.

Hereinafter the amplifying and transforming device 302 and the matching filter

304 are referred to as the demodulation part.

The spread spectrum signal generator 310 generates waveforms on the spread

spectrum data signal by using the waveform data stored on the internal template in the

spread spectrum encoding template storage device 314. When the spread spectrum

signal changes by a period of 25 times per lOOus. For example, when the spread

spectrum signal sweeps from 200Khz to 400Kh, jumps to lOOKhz, and sweeps back to

200Khz, the internal template stores the sampling values taken from the spread

spectrum power line signal at predetermined frequencies (for example 300) within a

predetermined period (for example lOOus). The spread spectrum signal generator

regenerates the original waveform from the sampling value, and generates the spread spectrum data signal.

Namely, the spread spectrum signal generator generates the spread spectrum

data signal that varies the carrier frequency depending upon binary data values within a

predetermined frequency range. Consequently, it is more effective at neutralizing the

effects of noise from the power line than it would be to use a single fixed carrier

frequency, therefore stable power line communication is made possible.

The CRC circuit 306 executes a 16-bit CRC operation for the data packets of the

demodulated signal by the matching filter 308. Namely, when the CRC circuit 306

finds the end of a packet, the CRC circuit 306 determines whether the packet is a

normal packet or an abnormal packet with errors. It is a matter-of-course that other

error checking operations can be applicable as well as the CRC operation. Hereinafter,

the means for an error checking operation including the CRC circuit 306 is

comprehensively referred to as an error detecting device.

The clock generator 312 inputs clock signal into the matching filter 304, the

spread spectrum signal generator 310, the CRC circuit 306 and the spread spectrum

encoding template storage device 314, and enables each of devices to operate according

to the clock.

FIG. 5-6 is a flow chart illustrating the communication initializing method for

and the slave mode power line communication device using spread spectrum in accordance with one preferred embodiment of the present invention. FIG. 5 represents

the communication initializing method wherein the master mode power line

communication device 110 automatically retrieves and registers the slave mode power

line communication device 100, and FIG. 6 represents the method wherein the master

mode power line communication device 110 registers the slave mode power line

communication device 100 by the request for registration from a slave mode power line

communication device 100 when the slave mode power line communication device 100

is added.

Referring to FIG. 5, firstly, the power line communication device reads the

requested data through an initial booting process when powered on, and sets the power

line communication device master mode (step 501). The master mode power line

communication device 110 broadcasts a master identifier to a plurality of slave mode

power line communication device 100.

The slave mode power line communication device 100 receives the master

identifier and registers it (step 505).

The master mode power line communication device 110 makes a request to

transmit a slave identifier (step 507). The slave mode power line communication

device 100 receiving the request for transmitting the slave identifier judges whether the

registered master identifier and the master mode power line communication device 110

transmitting the request coincides or not, and then transmits the slave identifier in response to the request, if, in fact, the registered master identifier and the master mode

power line communication device 110 do coincide (step 509). The master mode power

line communication device 110 receives the slave identifier and registers it (step 511).

The master mode power line communication device 110 broadcasts the received

and registered slave identifier to a plurality of slave mode power line communication

device 100 (step 513). The slave mode power line communication device 100

receiving the slave identifier registers the master mode power line communication

device 110 (step 515).

The master mode power line communication device 110 requests the slave

application resource information for slave application resource information (step 517).

The slave mode power line communication device 100 transmits the slave application

resource information to the master mode power line communication device 110 in

response to the request (step 519), the master mode power line communication device

110 receives the slave application resource information and stores it (step 521).

Namely, the power line communication device is able to automatically retrieve the

information about the peripheral devices when it is powered on. Consequently, the

power line communication device can be applied to the AMR, HA, and FA simply by

changing the application program without changing the power line communication

device whenever the meter, HA's peripheral device, and the FA's peripheral device (all

of which are coupled to the slave mode power line communication device 100) changes. Referring to FIG. 6, firstly, the slave mode power line communication device

100 reads the required data through the initial booting process when powered on, and

sets the power line communication device slave mode (step 601). The slave mode

power line communication device 100 transmits a request to register the slave identifier

to the master mode power line communication device 110. Hereinafter the illustrations

of steps 605-623 are omitted because of steps 605-623 are the same as steps 503-521 in

FIG. 5. In FIG. 6, different from that shown in FIG. 5, the master mode power line

communication device 110 is able to register the new added slave mode power line

communication device 100 when a new slave mode power line communication device

100 is added to the existing power line communication device together with a new

peripheral device. Also, in FIG. 6, the master mode power line communication device

110 is able to retrieve the information about the new added peripheral device.

FIG. 7 is a flow chart illustrating the power line communication method,

executed by the master mode power line communication device using spread spectrum,

together with the slave mode power line communication device in accordance with one

preferred embodiment of the present invention.

Referring to FIG. 7, firstly, the master mode power line communication device

110 sets the master mode and initializes when powered on (step 701), and executes the

communication initialization process that retrieves and registers the slave mode power

line communication device 100 (step 703). The master mode power line communication device 110 generates the spread

spectrum data signal from the spread spectrum signal generator 310, and transmits the

request signal that requests packet data be sent to one of the retrieved slave mode power

line communication devices 100 via the power line (step 705).

The master mode power line communication device 110 transmits the request

signal for sending packet data to the subsequent slave mode power line communication

device 100, receives the packet data until there is no more transmission of packet data,

and collects packet data from a plurality of slave mode power line communication

devices 100 step 707, 709.

FIG. 8 is a flow chart illustrating the power line communication method,

one preferred embodiment of the present invention.

Referring to FIG. 8, the slave mode power line communication device 100

executes the communication initialization process by registering the master mode power

line communication device 110 through the step 801-803. The slave mode power line

communication device 100 collects the data such as meter-reading data etc. from the

peripheral devices such as the meter etc. by means of the polling method (step 805, 813).

The slave mode power line communication device 100 transmits the meter-reading data

etc. to the master mode power line communication device 110 only, which corresponds to the master identifier registered, after the slave mode power line communication

device 100 received the packet which includes the request for sending the meter-reading

data etc. from the master mode power line communication device 110 (step 807, 811).

applied in the power line communication using spread spectrum in accordance with one

preferred embodiment of the present invention.

Referring to FIG. 9, the spread spectrum power line signal corresponds to the

physical layer of the OSI layer model, and comprises a start frame 901, a data link layer

header 903, a network layer header 905, an application layer header 907, data used for

transmission purposes 909 and data for error checking 911. This invention uses the

CEbus protocol to perform power line communication, and is able to enhance the

compatibility of the power line communication by means of performing the power line

communication especially at the OSI 7 layer.

from a master mode power line communication device using spread spectrum to slave

mode power line communication device in accordance with one preferred embodiment

of the present invention.

Referring to FIG. 10a, the packet comprises a header 1001 field, a master ID

1003 field, a slave ID 1005 field, a length 1007 field, a commandl009 field, an option

for command 1011 field and a server data 1013 field. The header 1001 field data represents the start of a frame, the master ID 1003

field data represents the identifier (ID) of the master mode power line communication

device 110, and the slave ID 1005 field data represents the identification of the slave

mode power line communication device 100.

The length 1007 field data represents the sum of the length of the command

1009 value, the option for command 1011 value, and the server data 1013 value. The

command 1009 field data represents the kind of command such as the command used to

request registration of a master identifier, and the command used to collect a packet by

the polling method. The option for command 1011 field data represents additional sets

(optional) necessary for the related command. The server data 1013 field represents

the data transmitted to a peripheral device such as a meter etc. from the manager server

140.

from a slave mode power line communication device using spread spectrum to a

Referring to FIG. 10b, the packet comprises a start frame 1015 field containing

data representing the start of the frame, a command 1009 field containing data

representing the kind of command, a slave serial number 1017 field containing data

representing the slave serial number, the slave ID 1005 field containing data

representing the identifier of the slave, bits for error checking 1019 and an end frame 1021 field containing data representing the end of the frame.

FIG. 10c is an illustration of the structure of packet that has been transmitted

from a peripheral device to a slave mode power line communication device using spread

spectrum in accordance with one preferred embodiment of the present invention.

Referring to FIG. 10c, the packet comprises a start frame header 1015 field

containing data representing the start of the frame, a command 1009 field containing

data representing the kind of command, a slave serial number 1017 field containing data

representing the slave serial number, a slave ID 1005 field containing data representing

the identifier of the slave, a source data 1013 field containing data representing the

meter-reading data etc., a status of peripheral 1023 field containing data representing the

status information of the peripheral device such as the status of the meter's power off,

bits for error checking 1019 and an end frame 1021 representing the end of the frame.

FIG. 11-13 is a rough block diagram of the AMR system using spread spectrum,

having power line communication devices using spread spectrum in accordance with

one preferred embodiment of the present invention. FIG. 14 and 15 are rough block

diagrams of the system wherein a power line communication device using spread

spectrum is applied to an HA in accordance with one preferred embodiment of the

present invention. FIG. 16 and 17 are rough block diagrams of the system wherein a

power line communication device using spread spectrum is applied to an FA in

accordance with one preferred embodiment of the present invention. Hereinafter, will primarily be an explanation of FIG. 11, and FIG. 12-17

focusing primarily on the differences between FIG. 12-17 and FIG. 11. FIG. 11

represents the AMR system that is embodied by installing a power line communication

device into a home's installed meter for electricity, water, or gas etc.

Referring to FIG. 11, the AMR system comprises a plurality of slave mode

power line communication devices 100 using the spread spectrum, a plurality of meters

104-1, ..., 104-i, ... (hereinafter referred to as 104), and the object for metering 102-1,

..., 102-i, ... (hereinafter referred to as 102) coupled to the slave mode power line

communication device 100, the master mode power line communication device 110

coupled to the slave mode power line communication device 100 through the power line,

a manager server 140 coupled to the master mode power line communication device 110

by way of the gateway 120 and the modem 130 through a leased line for data

communication, a measurement database 150 coupled to the management database 140,

a personal computer (PC) 160, a PCS phone 162 or a PDA 164 etc. coupled to the

manager server 140 through a wired or unwired network.

The power line communication device 100, 110 using spread spectrum is used as

a master or slave according to the mode set, and is involved with the power line

communication in the AMR system. The detailed explanation for the power line

communication device 100, 110 using the spread spectrum will be continued later.

The slave mode power line communication device 100 receives the meter- reading data etc. and transforms the meter-reading data etc into the spread spectrum

signal, and transmits the spread spectrum power line signal, which means the spread

spectrum signal carried on the power line, to the master mode power line

communication device 110. The master mode power line communication device 110

receives the spread spectrum signal, transforms the phase of the spread spectrum signal

into corresponding bit data (0, 1), and transmits the transformed signal to the gateway

120. The detailed explanation for the master mode power line communication device

110 and the slave mode power line communication device 100 will be continued later.

The gateway 120 transmits the data packet to the manager server 140 by way of

the modem 140. The manager server 140 processes the received data packet and is

able to apply the processed data packet to the function of telemetering.

FIG. 12-13 is a rough block diagram of the AMR system using spread spectrum,

one preferred embodiment of the present invention.

Referring to FIG. 12, the present invention, when applied to a large-scale

apartment complex, is able to embody the AMR system by installing the power line

communication device at the meters for electricity, water, and gas etc. that are installed

in each household of each apartment building. The users are able to check the results

of the telemetering provided from the manager server 140 by connecting to the manager

server 140 through a wired or unwired network such as via the Internet and/or the wireless Internet etc.

Referring to FIG. 13, each household in an apartment has a meter 104 installed,

collects the results of the telemetering from the slave mode power line communication

device 100, transmits the results to the master mode power line communication device

110 through the power line, the master mode power line communication device 110

transmits the results to the manager server 140 by way of the gateway 120 and modem

130 over a leased line such as PPP or ADSL etc., and stores the results in the

measurement database 150. A manager is always able to check the results of

telemetering daily, weekly or monthly.

FIG. 14 show a case wherein the power line communication device of the

present invention, using spread spectrum, is applied to the HA in multiple apartments,

and FIG. 14 represents the system used to remotely control the HA' peripheral devices

such as the light fixtures in each household in the apartment, the household electric

appliances for internet information, the security products, the HVAC (heating,

ventilation and air conditioning) such as an air-conditioner, or an audio/video device.

Referring to FIG. 14, the HA's controller 106 for controlling the HA's peripheral

devices of each household in each apartment is coupled to the slave mode power line

communication device 100 through a communication line such as a TP line, and the

slave mode power line communication device 100 is coupled to the master mode power

line communication device 110 through the power line. The other elements are the same as the elements in FIG. 1.

The users are able to remotely control the HA's peripheral device through the

wired or wireless Internet. Particularly, data transmission errors, due to the noises on

the power line, by remote control can be decreased by using the power line

communication device 100, 110 that employs spread spectrum, the noise reduction

method being a characteristic feature of the present invention. Also, the data relating

to an added peripheral device, collected by remote control, is able to be reflected by

using the following automatic retrieving function without it being necessary for a user

or a manager to change the related power line communication device or the settings for

the added peripheral device each time even when a new HA's peripheral device 105 is

added. This automatic retrieving function is also applied to the FA's remote control

system.

Referring to FIG. 15, the HA's controller 106 for controlling the HA's peripheral

device in one household of each apartment is coupled to the slave mode power line

communication device 100 via a communication line such as a TP line, and the slave

mode power line communication device 100 is coupled to the master mode power line

communication device 110 through the power line.

The master mode power line communication device 110 receives the command

for telemetering from the manager server 140, and transmits the command.

Consequently, the HA's controller is able to control (turn on or off) lights, security devices and air-conditioners etc., and to activate the devices at a predetermined hour by

means of remotely controlling the devices.

FIG. 16 and 17 are rough block diagrams of the system wherein the power line

communication device using spread spectrum is applied to FA in accordance with one

preferred embodiment of the present invention. The related system configuration is

the same as that of FIG. 15 and FIG. 17, and so the detailed description will be omitted.

A user of the present invention is able to remotely control a NC (Numerical

Control) type of machine tool, industrial robots and/or any kind of FA's peripheral

device etc. The power line communication device 100, 110, and likewise the HA's

peripheral devices, detects automatically any new added or changed peripheral devices

and transmits related information about the devices to the manager server 140 for the

purpose of enabling remote control of the devices.

FIG. 18 is a flow chart illustrating the remote meter reading process executed in

the AMR system in accordance with one preferred embodiment of the present invention

Referring to FIG. 18, firstly, the manager server 140 requests that the master

mode power line communication device 110 send the meter-reading data (step 1801),

the master mode power line communication device 110 transmits the request signal to

the slave mode power line communication device 100 (step 1803), the slave mode

power line communication device 100 transmits the request to the meter 104 (step 1805).

The meter-reading data is transmitted to the manager server 140 by way of the meter 104, the slave mode power line communication device 100 and the master mode power

line communication device 110 (step 1807, 1809, 1811). The manager server 140

collects the meter-reading data from a plurality of meter 104, processes the statistics of

the meter-reading data, and stores the meter-reading data (step 1813). The manager

server 140 is able to produce a power consumption report outlining the consumption

levels for a day, week, or month to the user, and is able to sends a receipt or notice of

payment to the user.

FIGS. 19 shows a window used to display the results of the remote meter

reading process. The manager server in the AMR system provides the results. Here,

for example, the results of the telemetering performed at each household of an

apartment will be illustrated.

Referring to FIG. 19, each household is allowed an account 1901 and the

sequence number 1905, and total power usage (consumption) 1903 of each account is

displayed. Also, when the user or the manager selects a predetermined account 1901,

the total usage 1907, monthly usage 1909, and monthly sum 1911 of the household

corresponding to the selected account, is displayed.

The user or the manager is able to check the daily usage 1921 by selecting a

predetermined date 1919.

Also, when the user selects the day 1913, the week 1915 or the month 1917, the

power consumption for that day, week, or month is displayed as a graph 1923. Although the present invention has been described in terms of various

embodiments, it is not intended that the invention be limited to these embodiments.

Modification within the spirit of the invention will be apparent to those skilled in the art.

Industrial Applicability

One advantage of the power line communication device using spread spectrum,

and also of the AMR system having the power line communication device, according to

the present invention, is that it can decreases data transmission errors that are generated

when the carrier of the predetermined frequency is affected by noise from the power

line.

Another advantage of the present invention is that it can provide power line

communication that is faster and more stable.

Still another advantage of the present invention is that it can provide protect by

preventing any intended leakage of transmission data when using a single carrier

frequency, and enhance the security of the power line communication

Still another advantage of the present invention is that it can minimize the

attenuation of a signal on the power line, and can make long distance transmission

possible by using the spread spectrum method.

Still another advantage of the present invention is that it can provide a multiple mode power line communication device that can be selectively used in master mode

or slave mode.

Still another advantage of the present invention is that it can provide the power

line communication device that is applicable to various peripheral devices without

necessitating the changing a power line communication device because of a change in

a peripheral device even when the peripheral device is exchanged

Still another advantage of the present invention is that it can provide various

interfaces applicable to not only the AMR systems, but also HA systems, FA systems

and building automation systems.

Claims

1. An apparatus for power line communication coupled to power line

using spread spectrum, comprising:

a power line transformer for transforming a spread spectrum power line

signal received from a first port to convert the spread spectrum power line signal

into a square wave, and then outputting the square wave at a second port, or for

transforming a spread spectrum data signal received from the second port and

then outputting the transformed spread spectrum data signal onto the power line

through the first port;

a matching filter for converting an output signal of said power line

transformer into digital data and outputting the digital data;

a spread spectrum signal generator for generating a spread spectrum data

signal which is a regenerated signal that regenerates the shape of the spread

spectrum signal by using sampled data of a waveform of the spread spectrum

signal, wherein the spread spectrum signal is a carrier frequency varying signal

within a predetermined frequency range, and the sampled data is previously

stored in a storage device;

a control device for receiving digital data via an external interface in

order to generate packet data, or for receiving the digital data from the matching a clock generator for synchronizing the matching filter, the spread

spectrum signal generator and said error detector in a same clock cycle.

5. The apparatus for power line communication of claim 1, wherein said

external interface comprises at least one selected from the group consisting of a

RS-232 interface, a SPI (Serial-Parallel Interface), an I2C interface and a CAN

(Control Area Network) interface in order to interface with a meter, an HA's

peripheral device and an FA's peripheral device.

6. A method for initializing power line communication, wherein the

method is executed using a power line communication system comprising a

power line, a plurality of slave mode power line communication devices coupled

to the power line, and a master mode power line communication device coupled

to said plurality of slave mode power line communication devices, said method

comprising the steps of:

transmitting a slave identifier to said plurality of slave mode power line

communication devices;

requiring said plurality of slave mode power line communication devices

to transmit their slave identifiers and then registering the slave identifiers;

transmitting the slave identifiers to at least one of the said plurality of

35 filter in order to interpret a command included in the digital data and execute an

action corresponding to the command; and

an external interface for interfacing said control device, matching filter

and spread spectrum signal generator with peripheral devices.

2. The apparatus for power line communication of claim 1, wherein the

conversion of said power line transformer's output signal into digital data is

performed by correlating the sampling data of the waveform of the spread

spectrum signal with the output of said power line transformer, and transforming

the output of said power line transformer into digital data.

3. The apparatus for power line communication of claim 1, the apparatus

further comprising:

an error detector, coupled to said matching filter and said spread

spectrum signal generator, for detecting errors in the digital data of the output

signal of the matching filter and transmitting the detection result to the control

device.

4. The apparatus for power line communication of claim 1, the apparatus

further comprising:

34 slave power line communication devices;

registering the master identifier when the master identifier is received

from said master mode power line communication device; and

registering said master mode power line communication device when the

slave identifier is received from said master mode power line communication

device, wherein the steps of transmitting a slave identifier, requiring, and

transmitting the slave identifiers is executed by said master mode power line

communication device, and the steps of registering the master identifier and

registering said master mode power line communication device is executed by

said slave mode power line communication device which executes said

communication initialization method in combination with said master mode

power line communication device.

7. The method for initializing power line communication of claim 6,

wherein said master mode power line communication device performs further

steps of requiring said plurality of slave mode power line communication

devices, which registered said master mode power line communication device,

for slave application resource information, and receiving the slave application

resource information.

8. A method for initializing power line communication, wherein the

method is executed using a power line communication system having a power

line, a plurality of slave mode power line communication devices coupled to

said power line and a master mode power line communication device coupled to

said a plurality of slave mode power line communication devices, said method

comprising the steps of:

transmitting a slave registration request signal to said master mode

power line communication device;

receiving a master identifier from said master mode power line

communication device;

registering the master identifier;

transmitting the slave identifier to said master mode power line

communication device in response to the request for transmitting a slave

identifier from said master mode power line communication device;

transmitting the master identifier to at least one of the plurality of slave

mode power line communication devices when receiving the slave registration

request signal;

requesting said slave mode power line communication device for the

slave identifier;

receiving the slave identifier; and registering the slave identifier, wherein the steps of transmitting a slave

registration request signal, receiving a master identifier, registering the master

identifier; transmitting the slave identifier; and the steps of transmitting the

master identifier, requesting, receiving the slave identifier; and registering the

slave identifier is executed by the master mode power line communication

device which executes said communication initialization method in combination

with said slave mode power line communication device.

9. A power line communication method executed by means of an

apparatus for power line communication using spread spectrum, said apparatus

comprising a spread spectrum signal generator for generating a spread spectrum

data signal which is a regenerated signal that regenerates the shape of the spread

spectrum signal by using sampled data of a waveform of the spread spectrum

within a predetermined frequency range, and the sampled data is previously

stored in a predetermined storage device, said power line communication

method comprising the steps of:

setting operating mode;

initializing power line communication between a master mode power

line communication device and a slave mode power line communication device; wherein the operating mode is set to a master mode, said power line

communication method executed in said power line communication device

comprises the steps of:

transmitting packet data including the request for sending meter-reading

data by means of a polling method to the slave mode power line communication

device registered by means of initializing power line communication;

receiving the meter-reading data from said slave mode power line

communication device;

transmitting the received meter-reading data to a manager server through

a gateway and a modem in order to provide an AMR service that processes the

meter-reading data and provides power usage reports for the users;

wherein the operating mode is set to a slave mode, said power line

communication method executed in said power line communication device

comprises the steps of :

receiving the meter-reading data from a meter by requesting the meter-

reading data from the meter;

receiving the packet data, which includes the request for sending meter-

reading data from the master mode power line communication device;

judging whether a previously registered master identifier and the master

identifier extracted from the received packet data are identical to each other; and transmitting the meter-reading data to the master mode power line

communication device when it is judged to be identical.

10. The power line communication method executed in a apparatus for

power line communication using spread spectrum of claim 1, wherein the master

mode and the slave mode are set by using a hardware technique which uses a dip

switch switchover.

11. The power line communication method executed in a apparatus for

power line communication using spread spectrum of claim 1, wherein the master

mode and the slave mode are set by using a software technique which receives

the packet including the master mode or the slave mode setting command from

the manager server via a network and interpreting the command.

12. An automatic meter reading system with a power line communication

device using spread spectrum comprising:

a first power line communication device coupled to a meter, the meter is

used for collecting and storing meter-reading data from at least one object of

metering, through an external interface, and collects the meter-reading data from

the meter;

a second power line communication device coupled to said first power line communication device via a power line, collects meter-reading data from a

spread spectrum power line signal; and

a manager server coupled to said second power line communication

device by way of a gateway and a modem through a wired or wireless network,

analysis the meter-reading data and displays the result of the analysis.

13. The automatic meter reading system with a power line communication

device using spread spectrum of claim 12, wherein said first power line

communication device and said second power line communication device

comprise respectively of:

a power line transformer for transforming a spread spectrum power line

transforming a spread spectrum data signal received from the second port and

then outputting the transformed spread spectrum data signal onto the power line

through the first port;

a matching filter for converting an output signal of said power line

transformer into digital data and outputting the digital data;

a spread spectrum signal generator for generating a spread spectrum data

signal which is a regenerated signal that regenerates the shape of the spread spectrum signal by using sampled data of a waveform of the spread spectrum

within a predetermined frequency range, and the sampled data is previously

stored in a storage device;

a control device for receiving digital data via an external interface in

order to generate packet data, or for receiving the digital data of the matching

filter in order to interpret a command included in the digital data and execute an

action corresponding to the command; and

an external interface for interfacing said control device, matching filter

and spread spectrum signal generator with peripheral devices.

14. An automatic meter reading system with a power line communication

device using spread spectrum of claim 13, wherein said external interface

comprises at least one selected from the group consisting of a RS-232 interface,

a SPI (Serial-Parallel Interface), an I2C interface or a CAN (Control Area

Network) interface in order to interface with a meter, an HA' peripheral device

or an FA' peripheral device.