JP2002077298A - Communication method and communication unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a communication method realizing smooth data communication, without increasing the transmission delay, even when a large number of communication units are connected on the same transmission path. SOLUTION: The communication method comprises a first step, where a slave unit is turned on to transmit a link establishment request frame, describing a code indicative of a link establishment request, a group code to which it belongs, and an address for specifying itself, a second step where a master unit in the group transmits a link establishment response frame describing a code indicating a link establishment request, a group code, and a code indicative of a signal transmission path being used for data communication with the master unit, in response to the link establishment request frame, and a third step for configuring a specific signal transmission path with the master unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication apparatus employing a multi-carrier modulation / demodulation system, and more particularly to a DMT (Discrete Multi Tone) modulation / demodulation system and OF.
The present invention relates to a communication method and a communication device that can realize data communication using an existing communication line by using a DM (Orthogonal Frequency Division Multiplex) modulation / demodulation method or the like.

[0002]

2. Description of the Related Art A conventional communication device will be described below. In recent years, to reduce costs and make effective use of existing facilities,
A “power line modem” that performs communication using an existing power line (light line) without adding a new communication line has attracted attention. The power line modem performs various processes such as control of the product and data communication by networking electrical products such as inside and outside the home, buildings, factories, and stores connected by the power line.

At present, such power line modems include:
An apparatus using the SS (Spread Spectrum) method has been considered. For example, when the SS method is used as a power line modem, the transmitting side modulates predetermined information and further performs spread modulation using a “spreading code” to increase the signal band by several tens to several thousand times. Spread and send. On the other hand, the receiving side performs spread demodulation (despreading) using the same spreading code as the transmitting side, and then demodulates the despread signal into the predetermined information.

In this case, a spreading code desirable for the SS system generally has a sharp peak in the autocorrelation characteristic,
M-sequence (Maximum-length lin
earshift-register sequence) is used.

On the other hand, as a communication device employing a modulation / demodulation method different from the communication device employing the SS method, there is, for example, a conventional communication device employing a multicarrier modulation / demodulation method. Here, the operation of a conventional communication device employing the multi-carrier modulation / demodulation method will be described.

First, as a multi-carrier modulation / demodulation method,
The operation of the transmission system of a conventional communication device employing the OFDM modulation / demodulation method will be briefly described. For example, when performing data communication using the OFDM modulation / demodulation method, the transmission system performs tone ordering processing, that is, processing for allocating transmission data of a transmittable number of bits to a plurality of tones (multicarriers) in a predetermined frequency band. Do. More specifically, for example, tone0 to toneX (X
Is an integer indicating the number of tones), transmission data of a predetermined number of bits is allocated. The transmission data is multiplexed for each frame by performing the tone ordering process and the encoding process.

Further, the transmission system performs an inverse fast Fourier transform (IFFT) on the multiplexed transmission data,
The parallel data after the inverse fast Fourier transform is converted into serial data, then the digital waveform is converted into an analog waveform through a D / A converter, and finally the data is transmitted through a transmission path through a low-pass filter.

Next, a conventional communication apparatus employing an OFDM modulation / demodulation method as a multicarrier modulation / demodulation method is described below.
The operation of the receiving system will be briefly described. As above, OFD
When performing data communication using the M modulation / demodulation method, the reception system applies a low-pass filter to the reception data (the transmission data described above), and then converts an analog waveform into a digital waveform through an A / D converter, and sends the data to a time domain equalizer. To perform adaptive equalization processing in the time domain.

Further, the receiving system converts the data after the adaptive equalization processing in the time domain from serial data to parallel data, performs a fast Fourier transform on the parallel data, and then performs frequency domain equalization by a frequency domain equalizer. Is performed.

[0010] The data after the adaptive equalization processing in the frequency domain is converted into serial data by a composite processing (maximum likelihood composite method) and a tone ordering processing, and thereafter, rate conversion processing and FEC (forward error correction) are performed.
on: forward error correction), descrambling, CRC (cy
Processing such as clic redundancy check is performed, and finally the transmission data is reproduced.

As described above, in the conventional communication apparatus employing the OFDM modulation / demodulation method, a high rate of data transmission can be achieved by utilizing the high transmission efficiency and the flexibility of functions which cannot be obtained by the CDMA or single carrier modulation / demodulation method. Communication is possible.

[0012]

The above-mentioned conventional communication apparatus has the following problems.

For example, FIG. 23 is a diagram showing a conventional connection example of a communication apparatus adopting the SS system or the multi-carrier modulation / demodulation system. Thus, in the prior art,
A plurality of communication devices (101, 102, 103, 104, 1
05) is connected to the same power line in the form of a bus, and as a method of controlling the network, for example, a token ring network has been used. However, in this method, only the node that has obtained the transmission right (token) can transmit data, and there is only one node having the transmission right in the network. Therefore, when a plurality of communication devices desire to transmit data at the same time, the transmission right cannot be easily obtained, and the transmission delay increases. This effect becomes more pronounced as the number of communication devices connected on the same transmission path increases.

Therefore, the conventional method of controlling a network in a communication apparatus has a problem that communication such as conversations and moving images that require real-time properties cannot be realized.

The present invention has been made in view of the above, and does not increase transmission delay even when the number of communication devices connected on the same transmission line increases.
An object of the present invention is to obtain a communication method and a communication device capable of realizing smooth data communication.

[0016]

Means for Solving the Problems The above-mentioned problems are solved,
To achieve the object, in the communication method according to the present invention, a powered-on slave device establishes symbol synchronization using a pilot frame output by a clock master, and then a code indicating a link establishment request, A first transmitting a link establishment request frame describing a group code to which the terminal belongs and an address for specifying the terminal;
And the master device of the group, as a response to the link establishment request frame, a code indicating the link establishment request, the group code, and a code indicating a signal transmission path used for data communication with the master device, The second transmitting the described link establishment response frame
And a third step in which the slave device receiving the link establishment response frame establishes a specific signal transmission path with the master device.

In the communication method according to the next invention,
Using the constructed signal transmission path, one of the devices transmits a training notification frame indicating a training start request to the other device, and then the other device responds to the training start request by the one device. A fourth step of transmitting a training notification frame indicating a training start request confirmation as a response to the first apparatus, the one apparatus transmitting a first training frame representing a known signal to the other apparatus, and thereafter, The other device receiving the second known signal also transmits a first training frame representing the known signal to the one device, and both devices individually receive equalizer coefficients and bitmaps. A fifth step of provisionally determining a parameter notification frame in which the provisionally determined bitmap is described. A sixth step of transmitting power to the destination apparatus and determining the power distribution when transmitting the own apparatus from the received bitmap, and the two apparatuses confirming the completion of the reception of the parameter notification frame by confirming the first parameter notification. A seventh step of transmitting to a partner apparatus using a training notification frame representing the second communication frame, and transmitting the second training frame representing a known signal to the other apparatus using the determined power distribution. The other device receiving the second known signal then transmits a second training frame representing the known signal to the one device, also using the determined power distribution, and both devices , Equalizer coefficient, bitmap, turbo encoder code length,
Tone ordering, AGC setting for FEQ, MTU length,
And an eighth step to formally determine the MINTU length,
A ninth step in which both of the devices transmit a parameter notification frame in which a bitmap, a turbo encoder code length, a tone ordering, an MTU length, and a MINTU length are officially determined to a partner device; Transmitting a completion of reception of the parameter notification frame to the partner device using a training notification frame indicating a second parameter notification confirmation.

In the communication method according to the next invention,
In a sense waiting state after completion of the training, when a transmission request is received from an upper layer and the respective frames or data communication frames used for normal data communication are not detected, the state shifts to a transmission state.
And after the completion of the transmission in the transmission state, a twelfth step of shifting to the sense waiting state again, and when the respective frames or the data communication frames are detected in the sense waiting state after the training is completed. A thirteenth step of shifting to the reception state, and a fourteenth step of shifting to the sense waiting state again when the frame received in the reception state is other than the training frame and the first parameter notification frame. A fifteenth step of shifting to the parameter calculation state when the frame received in the reception state is the training frame or the first parameter notification frame; and A sixteenth step of transitioning to a wait state. And it features.

In the communication method according to the next invention,
First, N (natural number) bytes of transmission data after Reed-Solomon error correction encoding are copied by M (natural number) sets, and the data is arranged in order to create an N × M byte data sequence.
In step 7 and a block interleaver of width N bytes × length M bytes, the data sequence is arranged in byte units in the horizontal direction, and the data after arrangement is read out in byte units in the vertical direction, An eighteenth step of rearranging and a nineteenth step of uniformly allocating the rearranged data sequence to each tone of a multicarrier by two bits per tone. .

In the communication device according to the next invention,
In a communication device employing a multi-carrier modulation / demodulation method, when power is turned on, after establishing symbol synchronization using a pilot frame output by a clock master,
A code indicating the link establishment request, a group code to which the self belongs, and an address for identifying itself, are transmitted, and thereafter, as a response to the link establishment frame, from the master device of the group, By receiving a link establishment response frame describing a code indicating the link establishment request, the group code, and a code indicating a signal transmission path used for data communication with the master apparatus, a specific signal transmission path with the master apparatus is received. Is constructed.

In the communication device according to the next invention,
A training notification frame indicating a training start request is transmitted to the other device by using the constructed signal transmission path, and then a training notification indicating a training start request confirmation is sent from the other device as a response to the training start request. Receiving a frame, and then transmitting a first training frame representing the known signal to the other device, and then from the other device,
Receiving a first training frame representing a known signal, and tentatively determining parameters including an equalizer coefficient and a bitmap based on the received frame;
Next, a parameter notification frame in which the provisionally determined bitmap is described is transmitted to the other device, and power distribution when the own device transmits from the bitmap described in the parameter notification frame received from the other device. Is determined, and then the completion of reception of the parameter notification frame from the other device is transmitted to the other device using a training notification frame indicating the first parameter notification confirmation, and the same is performed from the other device. Receiving a training notification frame and then using the determined power distribution to transmit a second training frame representing a known signal to the other device, and then from the other device a second training frame representing a known signal Training frames, and further, based on the received frames, equalizer coefficients, bitmaps, Encoder code length, tone ordering, FEQ for AGC setting, MTU length, and MINTU
Length, including the formal determination of the parameters, and then transmits a parameter notification frame in which the formally determined parameters are described to the partner device, receives a similar parameter notification frame from the other device, and finally, The completion of the reception of the parameter notification frame from the other device is transmitted to the other device by using a training notification frame indicating the second parameter notification confirmation.

In the communication device according to the next invention,
In the sense waiting state after the training is completed, a transmission request is received from an upper layer, and when the respective frames or data communication frames used for normal data communication are not detected, the state shifts to a transmission state and the transmission is performed. After completion of the transmission in the state, the state shifts to the sense waiting state again. On the other hand, when the respective frames or the data communication frames are detected in the sense waiting state after the training is completed, the state shifts to the reception state, and the reception is started. When the frame received in the state is other than the training frame and the first parameter notification frame, the state shifts to the sense waiting state again, and the frame received in the receiving state is the training frame or the first time. If the parameter notification frame, Proceeds to operation state, after the operation completion by the parameter operation state, characterized in that the process proceeds to again sense waiting state.

In the communication device according to the next invention,
The N (natural number) bytes of transmission data after Reed-Solomon error correction encoding are copied for M (natural number) sets, and the data is arranged in order to create an N × M byte data sequence. For the M-byte block interleaver, the data sequence is arranged in bytes in the horizontal direction, the arranged data is read out in bytes in the vertical direction, the data sequence is rearranged, and finally, the data sequence is rearranged. The data sequence after the replacement is equally allocated to each tone of the multicarrier by two bits per tone.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a communication device according to the present invention will be described in detail with reference to the drawings. In addition,
The present invention is not limited by the embodiment. That is, any communication device that performs data communication by the multi-carrier modulation / demodulation method can be applied to devices other than the power line modem.

Embodiment 1 In the present embodiment, a power line modem employing a multi-carrier modulation / demodulation method, specifically, a high-speed PLC (Power Line Carrier) modem device will be described as a communication device using an existing power line.

FIG. 1 is a diagram showing a configuration of a physical layer modulation / demodulation unit of a high-speed PLC modem device according to the present invention. In FIG. 1, 1 is a framing circuit, 2 is a mapper, and 3 is an inverse fast Fourier transform circuit (IFFT: Inverse).
Fast Fourier Transform, 4 is a digital / analog conversion circuit (D / A), 5 is a coupling circuit, 6 is a transmission line (power line), 7 is a control circuit, and 8 is an analog / digital converter. A digital conversion circuit (A / D), 9 is a carrier detection circuit, 10 is a symbol synchronization circuit, and 11 is a fast Fourier transform circuit (FFT: Fa)
st Fourier Transform), 12 is a demapper, 13 is a deframing circuit, 14 is a sample synchronization circuit, 15 is a transmission buffer, and 16 is a reception buffer.

The framing circuit 1, the mapper 2,
A transmission system is composed of the IFFT 3, the transmission buffer 15, and the D / A 4, and the A / D 8, the carrier detection circuit 9, the symbol synchronization circuit 10, the sample synchronization circuit 14, the reception buffer 16,
The FT 11, the demapper 12, and the deframing circuit 13 constitute a receiving system.

The high-speed PLC modem employs an OFDM modulation / demodulation method, which is a kind of frequency division multiplexing, as a multiplexing method. According to this method, tones are arranged most densely in frequency division multiplexing by using mutually orthogonal carriers (tones). FIG. 2 is a diagram showing a frequency band used in this communication and an application of each tone. Here, as shown in FIG. 2 (a), the frequency band of 4.3125
Up to 97 lines (12,3975 kHz to 44
8.5 kHz). FIG. 2 (b)
As shown in the figure, the application differs depending on the tone. Specifically, in the high-speed PLC modem device, the tones 32, 48, 64, 80,
Data communication is performed using all tones within tone 3 to tone 104 except for tone 96 and tones 56, 72, and 88 used as pilot tones.

FIG. 3 is a diagram showing the state of the CP symbol on the transmission path and the unit of the symbol input to the FFT. For example, the CP symbol (CPS)
16 samples of cyclic prefix (CP)
And a data portion of 256 samples, and one CP symbol is 272 samples. Therefore, the receiving side demodulates the data in a state where the CP inserted at a known timing is deleted (corresponding to “to demodulation FFT” in FIG. 3). The data portion is a minimum unit of communication, and represents a composite wave of all tones to be transmitted in a 256-point sample. The CP is inserted between symbols in order to prevent inter-symbol interference, and is obtained by duplicating and pasting the last 16 samples of the data portion, whereby the CP and the data portion are continuous. It becomes a waveform.

In communication of the high-speed PLC modem, the minimum unit of information transmission is a frame. FIG.
FIG. 3 is a diagram schematically showing a frame. As shown, the frame comprises a physical layer frame and a subsequent interframe gap. The gap is a period during which transmission is prohibited, and here, it is 2 CPS. The physical layer frame includes a preamble, a physical layer logical frame, and an EOF (End Of Frame). The physical layer logical frame includes a physical layer header, a physical layer additional payload, and an upper layer payload.

Here, a specific configuration of the frame generated by the framing circuit 1 will be described. In addition,
In the following, a frame structure excluding the priority control section from the physical layer frame is shown. First, FIG. 5 is a diagram illustrating a configuration of a link establishment frame. This link establishment frame is an AGC area for performing gain adjustment and carrier sense.
(Auto Gain Control), CRL (Correlation) representing a region to be subjected to correlation detection, PT (Pilot Tone) as a region for establishing clock synchronization, and a region for providing a reference phase for differential demodulation. DMY (Dummy
Data for DPSK), an FSC (Field Synchronization) area for a logical data boundary identification code area, and a CMID (Command Identi
fier) and GC (Group Co.)
de), DMY, and DU (Data Uni
t) and EOF, which is a code indicating the end of a frame, are used for a request for establishing a link and for responding to the request. For example, from a system in which a plurality of modem devices are connected in a bus, a clock master is used. And construct a tree-like system.

In this case, AGC corresponds to the preamble, CRL and PT correspond to the physical layer header,
MY, FSC, CMID, GC, and DMY correspond to the physical layer additional payload, and DU corresponds to the upper layer payload. In this frame, the CRL is CMD (Comman
d: code indicating that the command is indicated by CMID), and the CMID is LRQ (Link Establish R)
equest: link establishment request). Also, here
For convenience of explanation, it was decided to "construct a tree-like system centered on the clock master", but it is not limited to this,
For example, since the physical layer manages the clock and the network manages the network, another device may be the center of the tree.

FIG. 6 is a diagram showing a system configuration using the communication device according to the present invention (see (a)), and how a tree-like system is constructed (see (b)). Here, M is a master device (for example, a clock master), A1, B1, and C1 are submaster devices,
A2, A3, B2 and C2 are slave devices, and
M, A1, B1, and C1 form a GC: 0 group with M as the master, A1, A2, and A3 form a GC: 1 group with A1 as the master, and B1 and B2 form B1.
The following describes a case where a group of GC: 2 is formed with C as the master, and a group of GC: 3 is formed with C1 and C2 as the master of C1.

More specifically, for example, when the power is turned on to the high-speed PLC modem device A2,
The modem A2 establishes symbol synchronization using the pilot frame output from the clock master M, and then establishes a CRL.
, The LRQ as the CMID, the group code 1 to which the GC belongs, and the own address to the DU, and the link establishment frame described above is transmitted on the transmission path.

Thereafter, the high-speed PLC modem device A1, which is the master device of the group receiving the link establishment frame, sets CMD to CRL and LRQ to CMID.
Assigning the DU to the high-speed PLC modem device A2
D: 5 (the code indicating the signal transmission path: see FIG. 6B) is transmitted on the transmission path with the link establishment frame described therein. Here, all the devices perform a request / response process of link establishment using such a link establishment frame, and assign a code: LID indicating a transmission path to all the devices, so that a plurality of modem devices are connected in a bus. From the connected systems, build a tree-like system centered on the clock master.

As described above, according to the present embodiment, even when the number of high-speed PLC modem devices connected on the same transmission line increases, control using the CSMA system can be performed for each group. Smooth data communication can be realized without increasing transmission delay unlike the conventional token ring network system.

FIG. 7 is a diagram showing the structure of a training notification frame. This training notification frame includes AGC, CRL, PT, DMY, and FSC.
, A CMID, a GC, an LID (Link Identifier) which is an area of a code indicating a signal transmission path, and an EOF, and a training start request, a response to the request, and reception confirmation of a parameter notification frame described later. Used for notification. Here, AGC corresponds to the preamble, CRL and PT correspond to the physical layer header, and D
MY, FSC, CMID, GC, and LID correspond to the physical layer additional payload. Also, in this frame, CRL
Indicates CMD, and CMID indicates TRQ (Training Requests).
t: Training start request) or TCF (Training Confir)
m: Confirmation of training start request) or PCF1 (Parameter
Confirm: 1st parameter notification confirmation) or PCF2
(Second confirmation of parameter notification).

FIG. 8 is a diagram showing the structure of a training frame. This training frame is A
GC, CRL, PT, DMY, FSC, CM
ID, GC, LID, equalizer coefficient and SNR
It consists of a TRNS (Training Sequence), which is a code area for calculating (signal-to-noise ratio), and EOF, estimates transmission path characteristics, and sets various parameters.
Here, AGC corresponds to the preamble, and CRL and P
T corresponds to the physical layer header, DMY, FSC and CMID
, GC, LID, and TRNS correspond to the physical layer additional payload. In this frame, CRL indicates CMD, and CMID indicates TRNREQ1 (the first training frame transmitted by the training requesting node) or TRNREQ1.
It indicates NREQ2 (the second training frame transmitted by the training requesting node), TNRRES1 (the first training frame transmitted by the training responding node), or TNRRES2 (the second training frame transmitted by the training responding node).

FIG. 9 is a diagram showing the structure of a parameter notification frame. The parameter notification frame includes AGC, CRL, PT, DMY, and FSC.
, CMID, GC, LID, DU, and EOF, and notifies a training result (parameter). Here, AGC corresponds to the preamble, and CR
L and PT correspond to the physical layer header, and DMY, FSC and C
MID, GC, and LID correspond to the physical layer additional payload, and DU corresponds to the upper layer payload. In this frame, CRL indicates CMD, and CMID indicates PRT.
1 (Parameter: first training result) or PRT
2 (the second training result).

FIG. 10 is a diagram showing the structure of a data communication frame. This data communication frame is AG
C, CRL, PT, and FS which is an area of a code for match / mismatch detection between the transmitting modem and the receiving modem.
C / BDC (Bitmap Detection Code) and CMID
, GC, DMY, DU, and EOF,
Data notification is performed using the training result. Here, AGC corresponds to the preamble, CRL and PT correspond to the physical layer header, FSC / BDC, CMID and GC
And DMY correspond to the physical layer additional payload, and DU corresponds to the upper layer payload. In this frame, C
RL represents LID.

FIG. 11 is a diagram showing the structure of a pilot frame. This pilot frame is
1 and PT2, and transmits a sample / symbol clock reference signal.

FIG. 12 is a diagram showing the structure of a pilot request frame. This pilot request frame includes a repetition of PT1 and PT2, AGC, and CRL.
, PT, DMY, FSC, CMID, GC
, DMY, and EOF, and requests the restart of transmission of pilot tone frames. In this frame, C
RL indicates CMD, and CMID indicates WUR (Wake Up Requ
est: pilot tone frame transmission restart request).

Hereinafter, basic operations of the transmission system and the reception system will be described with reference to FIG. First, the operation of the transmission system will be described. For example, when transmission data is input to the physical layer modulation / demodulation unit of the high-speed PLC modem device, the framing circuit 1 performs a framing process (see FIGS. 5 and 7 to 7).
12), and outputs the frame to the mapper 2. Specifically, the framing circuit 1 first creates a physical layer payload by combining the physical layer additional payload and the upper layer payload. Further, a “bit string conversion process for preventing the transmission spectrum from concentrating on a specific frequency” by a scrambler, and R-
"Reed-Solomon encoding process" by S encoder,
The interleaver executes “bit string conversion processing for reducing errors due to burst noise”. Thereafter, the physical layer header is combined with the physical layer payload to create a physical layer logical frame.

In the mapper 2, first, the input bit sequence of the received frame is distributed to each tone according to the "tone ordering selection information" from the control circuit 7. Next, the bit string allocated to each tone is turbo-coded according to “Turbo code length selection information”. Then, the turbo-coded bit string is mapped (converts the bit string into complex data) according to the “bitmap selection information” and the “power distribution selection information”, and the result is output to IFFT3.

In IFFT3, the received data is subjected to inverse Fourier transform to convert the frequency domain data into time domain data, and output data of 256 samples is converted into 16 samples.
A sample CP is added to generate a CPS of 272 samples. Then, the transmission buffer 15 accumulates the IFFT3 output and uses the symbol synchronization clock to
Is output to D / A4.

In the D / A 4, a preamble is added to the received time domain data, the data after the addition of the preamble is converted into an analog signal in accordance with a sampling clock, and the analog signal is further converted to a coupling circuit 5.
Then, the data is transmitted to another communication device connected to the same power line via the transmission line 6.

Next, the operation of the receiving system will be described.
Here, for convenience of explanation, since only one communication device is connected to the transmission line 6, the description will be made using the configuration of the reception system in FIG. In the receiving system described below,
The symbol synchronization is established by the symbol synchronization circuit 10 using a pilot tone constantly transmitted from a communication device serving as a clock master (using a pilot frame transmitted intermittently when communication is not being performed). It is assumed that sample synchronization has been established by the synchronization circuit 14.

First, when multicarrier data is transmitted from the transmission system as described above, the reception system of another communication device performs an operation reverse to the operation of the transmission system and demodulates the data. Specifically, the A / D 8 fetching the multi-carrier data (analog signal) transmitted from the communication device on the transmission side via the coupling circuit 5 first samples according to a sampling clock. Then, the reception buffer 16 accumulates the sampling data, and converts the sampling data into an FF using the symbol synchronization clock.
Output to T11.

Subsequently, in the carrier detection circuit 9, the high-speed P
The presence of the LC signal in the transmission path is determined based on the AGC reception signal level, and the result is notified to the control circuit 7. The detection of the high-speed PLC signal is based on the CR
This is performed by L detection.

The FFT 11 performs a Fourier transform on the sampling data to convert a multicarrier signal in the time domain into data in the frequency domain, and furthermore, in the frequency domain data, a physical layer payload and a physical layer header. And outputs only the physical layer payload component to the demapper 12.

The demapper 12 first performs amplitude and phase equalization processing on the received frequency domain data in units of tones using the “FEQ coefficient selection information” specified by the control circuit 7. Next, using the "Turbo code length selection information" from the control circuit 7, turbo decoding is performed on the equalized data. Next, according to the “bitmap selection information” from the control circuit 7, the decoded data is converted into a predetermined bit string. Finally, according to the “tone ordering selection information” from the control circuit 7, the bit sequence is reconstructed, and the reconstructed (demodulated) bit sequence is output to the deframing circuit 13.

The deframing circuit 13 performs a process reverse to the framing process by the framing circuit 1 on the demodulated data, that is, performs a deinterleave process, an error correction process by Reed-Solomon, and descrambling. Then, only the upper layer payload component is extracted from the physical layer payload. Then, only the upper layer payload component is output to the upper layer.

The outline and basic operation of the high-speed PLC modem employing the multi-carrier modulation / demodulation method have been described above. Hereinafter, the operation of the high-speed PLC modem, which is a feature of the present invention, will be described in detail with reference to the drawings.

FIG. 13 is a diagram showing a state transition of the high-speed PLC modem device according to the present invention. The CRL shown
{A} [B] indicates that the code indicating “A” is encoded in the above-described CRL and “B” is encoded in the CMID. In addition, A / B indicates a transition condition, and B indicates an operation at the time of transition.

Specifically, first, the high-speed PLC modem device shifts to an initial setting state after power-on, and automatically establishes symbol synchronization and sample synchronization by using a pilot tone transmitted by the clock master, and then automatically. A transition is made (unconditionally) to the sense waiting state (step S1).
Next, the high-speed PLC modem device shifts to a transmission state when a predetermined transmission request described later is received and there is no carrier sense (CS) and pilot frame sense (PTFS) (step S2). The state immediately (unconditionally) shifts to the sense waiting state (step S3).

On the other hand, if there is carrier sense (CS) and pilot frame sense (PTFS), the flow shifts to the reception state (step S4). In the reception state, the above-described frame is received, and for example, the CRL is CMD and the CMID is TRN (TRNREQ1 or the like).
In cases other than PRT1 and PRT1, the state shifts to the sense waiting state (step S5). Also, CRL is CMD, and CMID is TRN (TRNREQ1 etc.) and PRT.
In the case of 1, the process shifts to the parameter calculation state (step S6), and immediately (unconditionally) shifts to the sense waiting state after the calculation is completed (step S7).

Hereinafter, the high-speed PLC in each of the above states will be described.
The operation of the modem device will be described in detail with reference to the individual drawings.

FIG. 14 is a diagram showing the operation of the high-speed PLC modem device in the initialization state. The high-speed PLC modem device that has transitioned to the initial setting state after power-on,
First, the H / W and S / W settings are made,
Y ", and unconditionally shifts to the PTFS waiting state (step S11).

Next, the high-speed PLC modem device that has shifted to the PTFS waiting state waits for a pilot tone for a predetermined time (step S12). For example, when the pilot tone is received, the high-speed PLC modem shifts to the clock synchronous state (step S13). ), Establish symbol synchronization using the pilot tone. After synchronization is established, high-speed P
The LC modem device releases “BUSY” and shifts to the sense waiting state (step S14).

On the other hand, if the pilot tone cannot be detected within the predetermined time, a PT request frame is transmitted. If the pilot tone cannot be detected still, the pilot tone detection processing within the predetermined time is further performed. , And the transmission process of the PT request frame are repeatedly executed a predetermined number of times (N times) (step S).
15). If the pilot tone cannot be detected despite N transmissions, the process shifts to the clock master function activation state (step S16), and the device itself becomes the clock master, and shifts to the sense waiting state (step S17). .

FIG. 15 is a diagram showing the operation of the high-speed PLC modem device in the sense waiting state. The high-speed PLC modem device that has shifted to the sense waiting state automatically shifts to the CS waiting / PTFS waiting state, and performs CS (carrier sense), PTFS (pilot tone frame sense), and transmission requests (Snd, TrnStartReq, TrnS) described later.
(tartRes, TrnReq, TrnRes, PrmReq, PrmRes). At this time, when there is no sense of CS and PTFS (step S21), when the transmission request is received from the upper layer (step S22), when there is no CS and the timeout of the PTFS wait occurs while waiting for the transmission request ( Step S23), the processing in the CS wait / PTFS wait state is continuously performed.

When there is CS or PTFS, the high-speed PLC modem device sets the transition operation to “B”.
USY ”, and shifts to the reception state (step S2).
4).

On the other hand, when there is a transmission request from the upper layer or while waiting for the transmission request, there is no CS and PTFS and P
If there is a TF (pilot frame), the high-speed PLC modem shifts to the transmission state (step S2).
5). If there is no CS at the time of PTF transmission, the high-speed PLC modem sets the operation at the time of transition to "BUSY" and shifts to the transmission state (step S26). If there is no CS and no PTFS while waiting for a transmission request, the high-speed PLC modem transmits a pilot request frame and shifts to a transmission state (step S2).
7). If there is a transmission request, there is no CS and PTFS, and there is no PTF, the high-speed PLC modem device:
A pilot request frame is transmitted while waiting for a transmission request, and the state shifts to a transmission state (step S28).

FIG. 16 shows a high-speed PL in the transmission state.
FIG. 4 is a diagram illustrating an operation of the C modem device. The high-speed PLC modem device that has transitioned to the transmission state is in a state other than the PTF transmission, that is, when its own device is not the clock master,
Transition to the physical layer payload construction state (step S3)
1) The framing circuit 1 performs a physical layer payload creation process. Thereafter, the state is unconditionally shifted to the scrambler state (step S32), the RS encoding state (step S33), the interleave state (step S34), and finally, to the physical layer logical frame / trailer construction state (step S34). S35), the processing by the framing circuit 1 ends.

On the other hand, the high-speed PLC which has shifted to the transmission state
In the case of PTF transmission, that is, when the modem device itself is the clock master, the modem device transitions to the physical layer logical frame / trailer construction state (step S36), and the framing is performed only by this process (the pilot frame generation process). The processing by the circuit 1 ends.

After the processing by the framing circuit 1 is completed,
The high-speed PLC modem shifts to the physical layer header mapping state by the mapper 2 when the transmission is not PTF transmission (step S48), and shifts to the physical layer payload mapping when the transmission is not PTF transmission (step S37). After that, transmission requests from the upper layer are other than Send (AL: LID request, AL.ack: LID distribution), TrnReq (request for training frame transmission by request side), Trn
In the case of Res (request for transmission of a training frame by the responding side), the flow shifts to the physical layer payload power control state (step S38). After setting the power distribution, the process by the mapper 2 ends, and the flow shifts to the IFFT input creation step. (Step S39). On the other hand, the transmission request from the upper layer is Send (AL, AL.ack), TrnStartReq
(Transmission request for training start request frame), Trn
StartRes (request for transmitting a training start request confirmation frame), PrmReq (request for transmitting parameters during training), PrmRes (notifying that the training result transmitted by the partner node has been correctly received),
In the case of transmitting a pilot request frame, the process directly proceeds to the IFFT input creation step without moving to the physical layer payload power control state (step S40). In the case of PTF transmission, the process directly goes to the IFFT input creation step without going to the physical layer payload mapping state (step S41).

After the processing by the mapper 2 is completed, the high-speed PLC modem apparatus, which has proceeded to the IFFT input creation step, unconditionally transitions to the IFFT state and the CP addition state by IFFT 3 (steps S42 and S43). In cases other than the transmission of the pilot request frame, the flow shifts to the preamble transmission state (step S45), and then shifts to the D / A4 symbol transmission state (step S46). On the other hand, in the case of PTF transmission and pilot request frame transmission, the process directly shifts to the symbol transmission state by D / A4 (step S44). Finally, a frame transmission completion notification is output to the upper layer, and the process shifts to the sense waiting state again (step S47).

FIG. 17 shows a high-speed PL in the reception state.
FIG. 4 is a diagram illustrating an operation of the C modem device. The high-speed PLC modem device that has shifted to the reception state first shifts to the gain adjustment state of the AFC amplifier, and after adjusting the gain for level detection, for example, when there is PTFS (when it is a pilot frame), the clock synchronization is performed. State (step S51), adjust the symbol synchronization clock,
After that, the processing shifts to the sense waiting state again (step S52).

On the other hand, when there is no PTFS (when the frame is other than the pilot frame), the high-speed PLC modem shifts to the correlation detection state (step S53), and continues the state until the CRL is detected (step S5).
4). Thereafter, if CRL cannot be detected or EOF has been detected even after 10 ms has elapsed, it is determined that the frame has not been detected, and the process proceeds to the sense waiting state (step S55). Therefore,
In this correlation detection state, only when CMD or LID is detected as CRL, the process shifts to the clock synchronization step (step S56), and fine adjustment of the clock is performed using the PT in the received frame. Then, after adjusting the clock, the process proceeds to the gain adjustment state (step S57),
Here, gain adjustment for performing FEQ processing is performed.

After that, when the correlation detection result is CMD, that is, when any one of the link establishment frame, the training notification frame, the training frame, the parameter notification frame, and the pilot request frame, the high-speed PLC modem device performs the DQPSK decoding. The process shifts to the mapper state (step S58), and the DQPSK demapper is set. After the setting is completed, the process unconditionally shifts to the symbol reception / field synchronization state (step S5).
9). On the other hand, when the correlation result is an LID, that is, in the case of a data communication frame, FEQ · M-QA
The state shifts to the M demapper / Turbo decoder / tone deordering state (step S60).
The state is unconditionally shifted to the symbol reception / field synchronization state (step S61).

After the transition to the symbol reception / field synchronization state, the high-speed PLC modem device
SC detection is performed. For example, when the FSC cannot be detected, the process returns to the correlation detection state (step S6).
2). On the other hand, when the FSC is detected, the flow shifts to the symbol reception / CMID state (step S63), and the CMID in the received frame is detected. Then, unconditionally, from symbol reception / CMID state, symbol reception / GC
The state shifts to the state (step S64).

In the symbol reception / GC state, for example, when CRL is LID and GC is other than the own group,
The high-speed PLC modem shifts again to the correlation detection state (step S65). When the CG is the own group and the CRL is the LID, that is, when the data communication frame is addressed to the own device, the high-speed PLC modem device shifts to the symbol reception / DU state (step S66).
The DU is received, and thereafter, the process again shifts to the sense waiting state (step S67).

In the symbol reception / GC state,
For example, CG is the own group, CRL is CMD, and C
MID is LRQ, TRQ, PRT1, PRT2, TC
F, PCF1, PCF2, high-speed PLC
The modem device shifts to the symbol reception / LID state (step S75). And the symbol reception / LID
In the state, if the LID is not the own LID, the high-speed PL
The C modem device determines that the frame is not a frame for itself and shifts to the correlation detection state again (step S6).
8). When the CRL is CMD and the CMID is TRQ, that is, in the case of a training start request of the training notification frame, the training request from the partner node is notified to the LME (Layer Management Entity) of the physical layer, and then the sensing is performed again. The state shifts to the waiting state (step S69). Also, if CRL is CMD and CMI
When D is the TCF, that is, in the case of confirming the training start request of the training notification frame, the reception of the training start request confirmation is notified to the LME of the physical layer, and thereafter, the process returns to the sense waiting state (step S6).
9). When the CRL is CMD and the CMID is PCF1 or PCF2, that is, in the case of confirming the parameter notification of the training notification frame, a normal reception notification of the training result from the partner node is notified to the LME of the physical layer, and then again The state shifts to the sense waiting state (step S69).

In the symbol reception / LID state, when the CRL is CMD and the CMID is LRQ, that is, in the case of a link establishment frame, the symbol reception / DID
The process shifts to the U state (step S70), receives the DU, and then shifts to the sense waiting state again (step S67). In the symbol reception / LID state, CRL is CMD and CMID is PRT1 or PRT.
In the case of T2, that is, in the case of the parameter notification frame, the state shifts to the symbol reception / DU state (step S
70) Receive DU. After that, symbol reception / DU
In state, CRL is CMD and CMID is PRT1
In the case of, that is, in the case of the first parameter notification frame, the upper layer is notified of the parameter reception notification at the time of training, and shifts to the parameter calculation state (step S71). On the other hand, CRL is CMD and CMID is PRT
In the case of 2, that is, in the case of the second parameter notification frame, the flow shifts to the sense waiting state again (step S67).

In the symbol reception / LID state, CRL is CMD and CMID is TRNREQ1, TNREQ.
RNREQ2, TRNRES1, or TRNRES2
In other words, in the case of a training frame, a notification of the reception of the training frame is sent to the LME of the physical layer, and thereafter, the state shifts to the symbol reception / TEQ coefficient calculation / SNR calculation state (step S72). The process unconditionally proceeds to the parameter calculation step (step S73).

FIG. 18 is a diagram showing the operation of the high-speed PLC modem device in the parameter calculation state. The high-speed PLC modem device that has shifted to the parameter calculation state
For example, if the CRL is CMD and the CMID is PRT1, that is, if it is the first parameter notification frame, the flow shifts to the power distribution calculation state (step S7).
6) After the power distribution calculation is completed, the process proceeds to the sense waiting state (step S77).

On the other hand, CRL is CMD and CMID is TR
In the case of NREQ1, TRNREQ2, TNRRES1, and TNRRES2, that is, in the case of a training frame, the flow shifts to the bitmap tone order calculation state (step S78), and after the calculation is completed, unconditionally shifts to the turbo code length calculation state (step S78). Step S7
9) After the operation is completed, the process further shifts to the sense waiting state (step S80).

As described above, the high-speed PLC modem apparatus of the present embodiment operates according to the state transitions shown in FIGS. 13 to 18 and performs data communication by changing frames according to the application. Therefore, even when the number of communication devices connected on the same transmission line increases, smoother data communication can be realized without causing a transmission delay.

Next, the operation related to the training in the state transition will be described in detail with reference to the drawings. In the high-speed PLC modem device, training is performed in order to provide a prescribed bit error rate (= 10 ⁻⁷ ) to an upper layer and to realize an optimum and high-speed information transmission rate.
In this training, transmission path characteristics are estimated by transmitting and receiving a known waveform, and based on the estimation result, optimal parameters necessary for transmitting and receiving a data communication frame are determined.

FIG. 19 is a diagram showing an example of parameters determined by training. In the present embodiment, the illustrated eight parameters (equalizer coefficient, power distribution, turbo encoder code length, bitmap, tone ordering, FEQ AGC setting, MTU length, MINTU
Length).

FIG. 20 is a diagram showing a training sequence according to the present embodiment. Hereinafter, the operation related to training will be described based on FIG. Here, the requesting high-speed PLC modem device is referred to as a requesting device, and the responding high-speed PLC modem device is referred to as a responding device.

(1) First, the requesting device transmits a training notification frame (CMID: TRQ) indicating a training start request to the device to be trained (step S81). Then, the responding device notifies the requesting device of the reception of the training start request by using a training notification frame (CMID: TCF) indicating the confirmation of the training start request (step S82). Here, the training notification frame shown in FIG. 7 is used.

(2) Next, the requesting device transmits a first training frame (CMID: TRNREQ1) representing a known signal required for training to the responding device (step S83). Thereafter, the responding apparatus that has received the first known signal similarly performs the first training frame (CM) representing the known signal necessary for training.
ID: TNRRES1) is transmitted to the requesting apparatus (step S84). At this time, both devices tentatively determine an equalizer coefficient and a bitmap from the above-mentioned parameters. Here, the training frame shown in FIG. 8 is used.

(3) Next, both devices store the temporarily determined bitmap in the parameter notification frame (CMI
D: Described in the DU of PRT1) and transmitted to the respective partner devices (steps S85 and S86). Then, based on the received bitmap, it determines the power distribution when the own device transmits. Here, the parameter notification frame shown in FIG. 9 is used.

(4) Next, both devices confirm that the parameter (bitmap) has been normally received by the training notification frame (C) indicating the first parameter notification confirmation.
Using MID: PCF1), each is transmitted to the partner device (steps S87, S88). Here, the training notification frame shown in FIG. 7 is used.

(5) Next, the requesting apparatus uses the determined power distribution to execute a second training frame (CMID: TRNRE) representing a known signal required for training.
Q2) is transmitted to the responding apparatus (step S89).
After that, the responding device that has received the second known signal,
Similarly, a second training frame (C) representing a known signal required for training using the set power distribution.
MID: TNRRES2) is transmitted to the requesting apparatus (step S90). At this time, in both devices, all the remaining parameters, ie, equalizer coefficients, bitmap, turbo coder code length, tone ordering, F
AGC setting for EQ, MTU length, and MINTU length
Formally decide. Here, the training frame shown in FIG. 8 is used.

(6) Next, both devices determine the bit map, turbo encoder code length, tone ordering, MTU length, and MINT from among the parameters determined above.
U length as parameter notification frame (CMID: PRT2)
DUs, and transmit them to the partner devices (steps S91 and S92). Here, the parameter notification frame shown in FIG. 9 is used.

(7) Next, both apparatuses confirm that the parameters (bitmap, turbo encoder code length, tone ordering, MTU length, and MINTU length) have been normally received by confirming the second parameter notification. Using the represented training notification frame (CMID: PCF2), each is transmitted to the partner device (steps S93 and S9).
4). Here, the training notification frame shown in FIG. 7 is used.

As described above, in the present embodiment, the configuration is such that the transmission path characteristics are estimated by the above-described procedure, and the optimum parameters necessary for transmitting and receiving a data communication frame are determined based on the estimation result. Therefore, a prescribed bit error rate (= 10 ⁻⁷ ) can be provided to the upper layer, and an optimum and high-speed information transmission rate can be realized.

In the present embodiment, data communication using a transmission line whose characteristics have not been investigated before the completion of training, that is, data communication that does not satisfy the prescribed bit error rate (= 10 ⁻⁷ ) is performed. A special communication method is used.

FIGS. 21 and 22 are diagrams showing a communication method applicable to a transmission line whose characteristics have not been investigated before the training is completed. Hereinafter, the communication method will be described. For example, in the case where transmission data of 228 bytes a to zz as shown in FIG. 21A is taken as an example, the communication device first performs Reed-Solomon error correction coding on the transmission data. The encoded data sequence is shown in FIG.
As shown in (b), a data sequence of 255 bytes is obtained by adding a Reed-Solomon redundancy code of 27 bytes of Ra to Rz to the transmission data of 228 bytes.

Next, in the communication device, the above-mentioned 255-byte data sequence is copied for 18 sets, and is copied as shown in FIG.
As shown in the figure, a 4590-byte data sequence (a1, b
1,... Rz1, A2, b2,..., Rz18). In this state, the communication device arranges a 4590-byte data sequence in the horizontal direction of the block interleaver of width 255 × length 18 in order as shown in FIG.
The arranged data is read out in the vertical direction, and the data series is rearranged.

Finally, in the communication device, the rearranged data series (a1, a2, a3,..., A18, b1, b2,
.., Rz18) are equally allocated to two tones of one tone in order from the tone 25, as shown in FIG. Here, a1, a2,.
Since it is composed of bytes (8 bits), one byte of data is allocated for every four tones.

As described above, if this method is used, even in a communication environment where the characteristics of the transmission line are not known and the state of the transmission line is not known,
Even in a communication environment in which a usable frequency band is noisy and the demodulation characteristics of data deteriorate in a normal communication method, if there are at least four tones having a low bit error rate,
Data communication can be performed reliably.

[0095]

As described above, according to the present invention, according to the present invention, a link establishment request frame in which a slave device describes a code indicating a link establishment request, a group code to which the slave device belongs, and an address for identifying itself. By transmitting a link establishment response frame describing a code indicating a link establishment request, a group code, and a code indicating a signal transmission path used for data communication with the master device, the master device of the group transmits The slave device establishes a specific signal transmission path with the master device.
Then, all devices perform link establishment request / response processing, and assign signal transmission paths to all devices, so that a system in which a plurality of communication devices are connected in a bus shape can be used as a tree structure centered on a clock master. Build a system. As a result, even when the number of communication devices connected on the same transmission path is increased, control using the CSMA method can be performed for each group, so that the transmission delay is reduced as in the conventional token ring network system. The effect is that smooth data communication can be realized without increasing the number of data transmissions.

According to the next invention, the transmission path characteristics are estimated, and the optimum parameters required for transmitting and receiving a data communication frame are determined based on the estimation result. The prescribed bit error rate (= 1
0 ^-7 ), and an optimum and high-speed information transmission rate can be realized.

According to the next invention, data communication is performed by operating according to the state transition and changing the frame according to the application. Therefore, when the number of communication devices connected on the same transmission path increases, Also, there is an effect that smoother data communication can be realized without causing a transmission delay.

According to the next invention, even in a communication environment in which the state of the transmission path is not known due to unexamined characteristics, or in a communication environment in which a usable frequency band has a lot of noise and a normal communication method deteriorates the data demodulation characteristic. Also in this case, if there are at least four tones having a low bit error rate, an effect is obtained that data communication can be performed reliably.

According to the next invention, a link establishment request frame in which a code indicating a link establishment request, a group code to which the self belongs, and an address for specifying itself are transmitted, and as a response, a master of the group is transmitted. A link establishment response frame describing a code indicating a link establishment request, a group code, and a code indicating a signal transmission path used for data communication with the master device is received from the device. As a result, it is possible to obtain a communication device capable of constructing a specific signal transmission path with the master device. In addition, all devices perform the request / response processing for establishing a link, and a signal transmission path is assigned to all devices, so that a system in which a plurality of communication devices are connected in a bus shape can be used as a tree centered on a clock master. This has the effect that a state-of-the-art system can be constructed.

According to the next invention, the transmission path characteristics are estimated, and the optimum parameters necessary for transmitting and receiving a data communication frame are determined based on the estimation result. The prescribed bit error rate (= 1
^0-7 ), and a communication device capable of realizing an optimum and high-speed information transmission rate can be obtained.
This has the effect.

According to the next invention, since data communication is performed by operating according to the state transition and changing the frame according to the application, the number of communication devices connected on the same transmission path increases. In this case, it is possible to obtain a communication device capable of realizing smoother data communication without causing a transmission delay.

According to the next invention, even in a communication environment in which the state of the transmission line is not known due to unexamined characteristics, or in a communication environment in which the demodulation characteristics of data are degraded in a normal communication method due to a large amount of noise in an available frequency band. In this case, if there are at least four tones having a low bit error rate, an effect is obtained that a communication device capable of reliably performing data communication can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a physical layer modulation / demodulation unit of a high-speed PLC modem device according to the present invention.

FIG. 2 is a diagram illustrating frequency bands used in communication and applications of each tone.

FIG. 3 is a diagram illustrating a state of a CP symbol on a transmission path and a unit of a symbol input to an FFT.

FIG. 4 is a diagram schematically illustrating a frame.

FIG. 5 is a diagram showing a configuration of a link establishment frame.

FIG. 6 is a diagram showing a system configuration using a communication device according to the present invention and a state of constructing a tree-like system.

FIG. 7 is a diagram illustrating a configuration of a training notification frame.

FIG. 8 is a diagram showing a configuration of a training frame.

FIG. 9 is a diagram showing a configuration of a parameter notification frame.

FIG. 10 is a diagram showing a configuration of a data communication frame.

FIG. 11 is a diagram showing a configuration of a pilot frame.

FIG. 12 is a diagram showing a configuration of a pilot request frame.

FIG. 13 is a diagram showing a state transition of the high-speed PLC modem device according to the present invention.

FIG. 14 is a diagram illustrating an operation of the high-speed PLC modem device in an initialization state.

FIG. 15 is a diagram illustrating an operation of the high-speed PLC modem device in a sense waiting state.

FIG. 16 is a diagram illustrating an operation of the high-speed PLC modem device in a transmission state.

FIG. 17 is a diagram illustrating an operation of the high-speed PLC modem device in a reception state.

FIG. 18: High-speed PL in a parameter calculation state
FIG. 4 is a diagram illustrating an operation of the C modem device.

FIG. 19 is a diagram showing an example of parameters determined by training.

FIG. 20 is a diagram showing a training sequence.

FIG. 21 is a diagram illustrating a communication method applicable to a transmission line whose characteristics have not been investigated before training is completed.

FIG. 22 is a diagram illustrating a communication method applicable to a transmission line whose characteristics have not been investigated before training is completed.

FIG. 23 is a diagram illustrating a problem.

[Explanation of symbols]

1 framing circuit, 2 mapper, 3 inverse fast Fourier transform circuit (IFFT), 4 digital / analog converter circuit (D / A), 5 coupling circuit, 6 transmission line (power line), 7 control circuit, 8 analog / digital converter circuit (A / D), 9 carrier detection circuit, 10 symbol synchronization circuit, 11 fast Fourier transform circuit (FFT), 12
Demapper, 13 deframing circuit.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H04L 12/40 H04L 11/00 321 29/08 13/00 307A (72) Inventor Hidenobu Fukushima Marunouchi 2-chome, Chiyoda-ku, Tokyo 2-3 No. 3 Mitsubishi Electric Co., Ltd. (72) Inventor Teruko Fujii 2-3 No. 2-3 Marunouchi, Chiyoda-ku, Tokyo F-term (reference) 5J065 AC02 AD11 AG06 5K022 DD01 DD13 DD19 DD23 DD33 5K032 AA02 AA09 CC01 DA01 DB14 DB18 5K033 AA02 AA09 CB01 DA01 DB09 DB11 5K034 AA02 AA03 AA20 BB03 DD02 EE05 FF05 HH01 HH02 HH04 HH16 HH63 KK08

Claims (8)

[Claims] 1. A communication method using a multi-carrier modulation / demodulation method, wherein a powered-on slave device establishes symbol synchronization using a pilot frame output by a clock master, and then a code indicating a link establishment request. A first step of transmitting a link establishment request frame describing a group code to which it belongs and an address for identifying itself, and the master device of the group transmits the link establishment request as a response to the link establishment request frame. A second step of transmitting a link establishment response frame that describes a code indicating the code, the group code, and a signal transmission path used for data communication with the master device; and the slave receiving the link establishment response frame. The device establishes a specific signaling path with the master device A communication method, comprising: a third step. 2. Using the established signal transmission path, one of the devices transmits a training notification frame indicating a training start request to the other device, and thereafter,
A fourth step in which the other device transmits a training notification frame indicating a training start request confirmation as a response to the one device in response to the training start request; Transmitting the training frame to the other device, and then receiving the first known signal, the other device similarly transmits a first training frame representing the known signal to the one device, A fifth step in which both devices individually temporarily determine an equalizer coefficient and a bitmap, and the two devices send a first parameter notification frame in which the temporarily determined bitmap is described to a partner device. A sixth step of deciding the power distribution at the time of transmitting the own apparatus from the transmitted and received bitmap; A seventh step of transmitting the completion of reception of the data notification frame to the partner apparatus using a training notification frame representing the first parameter notification confirmation, and the one apparatus uses a determined power distribution to generate a known signal. A second training frame representing the other device is transmitted to the other device, and then the other device receiving the second known signal, similarly using the determined power distribution,
A second training frame representing the known signal is transmitted to the one device, and both devices determine the equalizer coefficients, bitmap, turbo coder code length, tone ordering, F
AGC setting for EQ, MTU length, and MINTU length
Eighth step of formally determining, and the two apparatuses send the second parameter notification frame in which the bitmap, turbo encoder code length, tone ordering, MTU length, and MINTU length that are formally determined are described to the partner apparatus. And a tenth step in which both devices transmit the completion of reception of the parameter notification frame to the partner device using a training notification frame indicating a second parameter notification confirmation. The communication method according to claim 1, comprising: 3. In the sense waiting state after completion of the training, when a transmission request is received from an upper layer and the respective frames or data communication frames used for normal data communication are not detected, the state shifts to the transmission state. An eleventh step of shifting; a twelfth step of shifting to the sense waiting state again after the transmission is completed in the transmission state; and detecting each of the frames or the data communication frames in a sense waiting state after the completion of the training. A thirteenth step of shifting to the reception state when the frame is received, and a step of shifting to the sense waiting state again when the frame received in the reception state is other than the training frame and the first parameter notification frame. 14; and the frame received in the reception state is the In the case of training frame or the first parameter notification frame, first to migrate to the parameter arithmetic state
The communication method according to claim 2, further comprising: a fifth step; and a sixteenth step of, after completion of the operation in the parameter operation state, shifting to the sense waiting state again. 4. The method according to claim 1, wherein N is a value of N after Reed-Solomon error correction coding.
A seventeenth process of duplicating M (natural number) sets of transmission data of (natural number) bytes and arranging them in order to create an N × M byte data series, and a block interleaver of width N bytes × length M bytes An eighteenth step of arranging the data series in byte units in the horizontal direction, reading the arranged data in byte units in the vertical direction, and rearranging the data series; and The method according to claim 1, further comprising: allocating to each tone of a multi-carrier, two bits per tone equally. 5. A communication apparatus adopting a multi-carrier modulation / demodulation method, wherein when power is turned on, after a symbol synchronization is established using a pilot frame output by a clock master, a code indicating a link establishment request belongs to itself. A link establishment request frame describing a group code and an address for identifying itself is transmitted, and then, as a response to the link establishment frame,
From the master device of the group, a code indicating the link establishment request, the group code, and a code indicating a signal transmission path used for data communication with the master device,
By receiving the link establishment response frame that describes
A communication device for establishing a specific signal transmission path with a master device. 6. A training notification frame indicating a training start request is transmitted to the other device using the constructed signal transmission path, and thereafter, a training start request is transmitted from the other device as a response to the training start request. Receiving a training notification frame representing a confirmation, then transmitting a first training frame representing a known signal to the other device, and then receiving a first training frame representing a known signal from the other device; Furthermore, based on the received frame, a parameter including an equalizer coefficient and a bitmap is provisionally determined. Then, a parameter notification frame in which the provisionally determined bitmap is described is transmitted to the other device, and the other device is transmitted. Via the parameter notification frame received from the device The power distribution at the time of transmitting the own device is determined from the map, and the completion of reception of the parameter notification frame from the other device is determined by using the training notification frame representing the first parameter notification confirmation. And receives a similar training notification frame from the other device. Then, using the determined power distribution,
Transmitting a second training frame to the other device, and then receiving a second training frame representing the known signal from the other device, and further, based on the received frame, an equalizer coefficient, a bitmap, Turbo encoder code length, tone ordering, FEQ
Parameters including the AGC setting, the MTU length, and the MINTU length are formally determined. Next, a parameter notification frame in which the parameters that have been formally determined are described is transmitted to the partner apparatus, and similar parameter notification is performed from the other apparatus. Receiving a frame, and finally transmitting the completion of reception of the parameter notification frame from the other device to the other device by using a training notification frame representing a second parameter notification confirmation. 6. The communication device according to 5. 7. In a sense waiting state after completion of the training, when a transmission request is received from an upper layer and the respective frames or data communication frames used for normal data communication are not detected, the state shifts to the transmission state. After the completion of transmission in the transmission state, the state shifts again to the sense waiting state. On the other hand, in the sense waiting state after the completion of the training, when the respective frames or the data communication frames are detected, the state shifts to the reception state. When the frame received in the receiving state is other than the training frame and the first parameter notification frame, the process again shifts to the sense waiting state, and the frame received in the receiving state is the training frame. Or of the first parameter notification frame The case, the process proceeds to parameter calculation state, after the operation completion by the parameter operation state, communication apparatus according to claim 6, characterized in that the process proceeds to again sense waiting state. 8. N after Reed-Solomon error correction coding
(Numerical number) bytes of transmission data are duplicated by M (Numerical number) sets, and they are arranged in order to create an N × M byte data sequence. Then, for a block interleaver of width N bytes × length M bytes, The data series is arranged in bytes in the horizontal direction, and the arranged data is read out in bytes in the vertical direction, and the data series is rearranged. 7. The communication apparatus according to claim 5, wherein two bits are equally assigned to one tone for each tone.