CN103004123A

CN103004123A - Method of adapting fec codeword to physical resource block, method of synthesizing fec codeword and system thereof

Info

Publication number: CN103004123A
Application number: CN2012800016808A
Authority: CN
Inventors: 赵泉波; 孙方林; 张晓风; 张利
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2012-09-12
Filing date: 2012-09-12
Publication date: 2013-03-27
Anticipated expiration: 2032-09-12
Also published as: WO2014040247A1; CN103004123B

Abstract

The invention relating to the communication field provides a method of adapting FEC codewords to a physical resource block, a method of synthesizing FEC codewords and a system thereof. The method of adapting FEC codewords to a physical resource block comprises the following steps: in the appointed time period, a first physical resource block assigned to a user is adptoed as the initial position of FEC codewords for loading data; if the remaining portion of a last physical resource block assigned to the user is not large enough to load an FEC codeword, the remaining portion of the last physical resource block is filled with invalid data; or based on the length of the remaining portion, a shortened FEC codeword is adopted and the length of the FEC codeword is kept unchanged.

Description

The FEC code word is to adaptation method, FEC code word method for synchronous and the system of Physical Resource Block

Technical field

The present invention relates to the communications field, relate in particular to a kind of FEC code word to adaptation method, FEC code word method for synchronous and the system of Physical Resource Block.

Background technology

EOC (Ethernet over Cable) refers to the technology general designation at the transmission over coaxial cable Ethernet data.The EOC technical scheme of industry is varied now, and scale, maturity differ, and mainly are divided into passive baseband EOC and active modulation EOC two classes.Passive baseband EOC system is by carrying out two or four conversion and the laggard row transfer of data of coupling to data-signal, the relative cheap and simple of the equipment that is characterized in, but poor to network adaptability, can not pass the equipment such as activated amplifier and passive tapping distributor, also be only applicable to star-like centralized distribution network; Active modulation EOC is by carrying out the laggard row transfer of data of modulation /demodulation to data, but its transparent transmission amplifier, branch distributor, can be applied to Star Network and tree network, some ad hoc network (as addressing system is arranged in the network) is also had good adaptability.

The EoC technology adopts point-to-multipoint user network topological structure, utilizes the original coaxial cable of broadcasting and TV to realize the Full-Services access of data, voice and video.A typical active modulation EOC system partly is comprised of head end, terminal, Coaxial distribution network etc.Head end generally is placed on the optical node position, plays distribution upper strata Ethernet data, the effect of convergence terminal equipment; Terminal is placed on user's family and serves as home terminal cat access user computer or interactive machine top box; The Coaxial distribution network network is exactly from CATV (Cable Television, cable TV) optical node position to the network of user's family, except coaxial cable, also includes the equipment such as source amplifier, EOC jumper, branch distributor.

PON (Passive Optical network, EPON) technology is a kind of Optical Fiber Transmission and access technology of point-to-multipoint, descending employing broadcast mode, up employing time division multiple access way, can form neatly the topological structures such as tree type, star-like, bus-type, do not need node device at optical branch point, only need to install a simple optical branching device and get final product.

The topological structure of tree type is existing passive optical-fiber network a kind of topological structure commonly used, it comprises optical line terminal (the Optical Line Terminal of innings side, OLT), the optical network unit of user's side (Optical Network Unit, ONU) or Optical Network Terminal (Optical Network Terminal, ONT) and Optical Distribution Network (optical distribution network, ODN).So-called " passive " refers to not contain among the ODN any active electronic device and electronic power supply, all be comprised of passive devices such as optical branching devices (Splitter), so the cost of its management maintenance is lower.

In the PON system, OLT is down direction to the transmission direction of ONU, adopts the TDM mode, i.e. downlink data transmission is continuous, each ONU that issues with information broadcasting that OLT is continuous, and each ONU selects one's own data receiver.

ONU adopts the TDMA mode to the up direction that is transmitted as of OLT, and namely upstream data sends and happens suddenly, and different ONU take different ascending time slots, and a plurality of ONU share up link by time-multiplexed mode.The guard time interval that avoids conflict is arranged between each ascending time slot.

In order to guarantee that upstream data can not clash, up transmission need to be adopted ranging technology, measure the descending loop time delay that sends to the data-signal of uplink receiving of OLT, and carry out accordingly delay compensation, guarantee that upward signal at each ONU is after common optical fiber is converged, insert the time slot of appointment, neither bump to each other, also the gap is too not large.

IEEE is organized in the formal 802.3ah of establishment of calendar year 2001 working group, i.e. first mile Ethernet (the Ethernet for the First Mile of EFM working group is otherwise known as, EFM), mainly carry out optical fiber access technology EPON (the Ethernet Passive Optical network take Ethernet Ethernet technology as core integration PON technology, ethernet passive optical network) standardization effort, and formally promulgate with in June, 2004.The EPON technology has been inherited the low cost of Ethernet and the high bandwidth of ease for use and optical-fiber network, has good cost performance.After the formal issue of EPON international standard, the industrial chain of EPON has reached its maturity and Scaledeployment has been arranged at present.

Along with popularizing of network application, various emerging enhancing business have been accelerated the bandwidth demand lifting, and the ieee standard tissue begins to consider the standardization of 10G EPON, and in the formal IEEE 802.3av working group that sets up of in September, 2006.The target of IEEE802.3av working group be define 1Gbps up/the descending dissymmetric network framework of 10Gbps and 10Gbps be up/the descending symmetrical network framework of 10Gbps and satisfy the light access technology that the physical layer error rate is not more than the point-to-multipoint of 10-12, also will consider simultaneously the coexistence problems of 1G EPON system and 10G EPON system.

EPOC (EPON over COAX), namely ripe EPON technology is introduced COAX (coaxial cable, coaxial cable), be CNU (Coax Network Unit, coaxial network unit) the upper MAC (Media Access Control, medium access control) that realizes EPON, the OLT of EPON can directly control the CNU in copper territory, at OLT, the ONU difference of CNU and EPON is only in physical layer.CMC (COAX Media Converter, coaxial cable medium converter) compares former EOC node and will simplify like this, and OLT can manage end to end to CNU.

In the EPOC system, CMC is as the change of medium equipment between coaxial and the light, and CMC has multiple implementation at present:

(1) No-MAC scheme:

Only defined physical layer on the CMC, CMC only does the conversion of physical medium, without the MAC function; The timeslice of Coax section and fiber section is distributed by the OLT unified management;

(2) 1.5MAC scheme:

MAC layer definition arranged on the CMC (IND), but the MAC layer of CMC does not carry out allocated bandwidth to the CNU in copper territory, but according to the bandwidth allocation information of OLT, resolve, translate into time corresponding to coax;

(3) 2MAC scheme:

PON and EOC section adopt independently bandwidth scheduling, the allocated bandwidth of intermediate equipment CMC complete independently EOC section.

FEC (Forward Error Correction, forward error correction mode) coding refers to that transmitting terminal sends the coding that can correct a mistake, according to the code and the coding rule that receive, automatically corrects the mistake that occurs in the transmission at receiving terminal.FEC is coded in the optical transmission system and is generally used, and can improve preferably the optical-fiber network performance, as increasing the transmission range of optical communication system, reduces the optical transceiver transmitting power, reduces receiver sensitivity etc.

RS (reed solomon, reed-solomon) code is a kind of FEC coding, is suitable for correcting this class burst error, and the major parameter of the RS code that can correct T wrong code element is as follows:

(1) code length N=2m-1 code element;

(2) supervise code element is counted N-K=2T code element;

(3) minimum distance dmin=2T+1 code element.

Wherein m represents the bit number of each code element, such as the RS (255,239) that GPON (gigabit-capable pon) uses, and m=8, each code element is a byte.

At OFDMA (Orthogonal frequency division multiple access, the OFDM access) in the point-to-multipoint system, local side is responsible for distributing each user in the time-frequency piece resource of up-downlink direction, informs the time-frequency block message of its up-downgoing of user by specific field (such as MAP (mapping) message) in each downlink frame.At down direction, the user receives and extracts data according to the information of MAP indication at the time-frequency piece under own; At up direction, the user sends data according to the information of MAP indication at the time-frequency piece under own.

The OFDMA system of prior art, such as WIMAX (Worldwide Interoperability for Microwave Access, the worldwide interoperability for microwave access), LTE ((Long Term Evolution, Long Term Evolution) etc., the size of FEC code word and the Physical Resource Block of OFDMA, namely two-dimentional time/frequency source block is also referred to as PRB (Physical Resource Block, Physical Resource Block) equal and opposite in direction, or the integral multiple of PRB.

There is following shortcoming in the OFDMA system of the prior art:

(1) be subject to the size of PRB, the code length of WIMAX, LTE definition is all less, is no more than 100 bytes, and coding gain is limited;

(2) WIMAX, LTE system need to define and support more code word, with the PRB of applicable different sizes;

(3) modulation system of inner each subcarrier of the PRB of WIMAX, LTE system all is the same, and the modulation bit number all is even number, and the EPOC system is different in the modulation system of each subcarrier of a PRB inside, and the debud mode of supporting is more, if adopt the size of FEC code word and the equal-sized mode of PRB of OFDMA, to need to define more FEC code word, bring the complexity of system.

In addition, the 10G EPON of prior art is that the FEC code word has designed a kind of special 64/66B pattern, and it is synchronous by this synchronous pattern acquisition code word of search to have defined a synchronous state machine at receiving terminal.

There is following shortcoming in the 10G EPON of the prior art: the code word method of synchronization of 10G EPON is adapted to continuous system, be not suitable for the burst system, such as the OFDMA scene, be that every secondary burst receiving terminal all needs to carry out first FEC code word synchronously (finding codeword boundary), may need the outer resource of occupying volume to come synchronously.

Summary of the invention

The embodiment of the invention provides the adaptation method of a kind of FEC code word to Physical Resource Block, and coding gain is limited, needs define and support more code word with the Physical Resource Block of applicable different sizes, the problem of system complex because the size of FEC code word causes with the Physical Resource Block correspondence to be intended to solve the prior art existence.

On the one hand, the adaptation method of a kind of forward error correction mode FEC code word to Physical Resource Block is provided, described method comprises: within the time cycle of agreement, first Physical Resource Block of distributing to the user is that the original position of FEC code word begins to carry data, be not enough to carry a FEC code word if distribute to the remainder of last Physical Resource Block of user, then this remainder is filled invalid data or according to the length of this remainder, the FEC code word is adopted shortening FEC code word, and described FEC code word adopts regular length.

On the other hand, provide the adaptation method of a kind of forward error correction mode FEC code word to Physical Resource Block, described method comprises:

Within the time cycle of agreement, according to first Physical Resource Block of distributing to the user of the mapping MAP administrative messag in current period indication current period or distribute to the processing mode of last Physical Resource Block of user.

On the one hand, provide a kind of forward error correction mode FEC code word method for synchronous again, described method comprises:

Receive physical frame;

Detect described physical frame, obtain frame synchronization;

Resolve the mapping MAP message of broadcasting, determine the Physical Resource Block to each user assignment;

Rule is determined the mode that code word is delimited according to a preconcerted arrangement;

Extract the FEC code word by fixing code length from the Physical Resource Block that distributes, rule is correspondingly processed to the remainder of last Physical Resource Block of the time cycle of agreement according to a preconcerted arrangement.

On the one hand, provide a kind of forward error correction mode FEC code word synchro system again, described system comprises:

Receiver module is used for receiving physical frame;

Detection module, the physical frame for detection of described receiver module receives obtains frame synchronization;

Parsing module is used for resolving the mapping MAP message of broadcasting, and determines the Physical Resource Block to each user assignment;

Determination module is used for according to a preconcerted arrangement rule, determines the mode that code word is delimited; With

Extraction module is used for extracting the FEC code word from the Physical Resource Block that distributes by fixing code length, and rule is correspondingly processed to the remainder of last Physical Resource Block of time cycle of arranging according to a preconcerted arrangement.

Because the FEC code word in the fec frame that the embodiment of the invention provides adopts regular length, support code word number and system complexity thereby reduce system; In addition, because in the time cycle of agreement, be not enough to carry a FEC code word if distribute to the remainder of last Physical Resource Block of user, then according to the length of this remainder, the FEC code word is adopted shortening FEC code word, code carries useful data thereby the remainder that makes last Physical Resource Block adopts shortening FEC, has therefore improved resource utilization; In addition and since within the time cycle of agreement the original position of FEC code word with distribute to the aligned in position of first Physical Resource Block of user, therefore do not need additionally to increase the indication of FEC border, receive the recovery that FEC when wrong can the cycle and set the border MAP occurring.

Description of drawings

Fig. 1 is the PRB schematic diagram of OFDMA system in the embodiment of the invention one.

Fig. 2 is the schematic diagram of distributing to certain user's PRB in the embodiment of the invention one in designated time length.

Fig. 3 and Fig. 4 are that the FEC code word that provides of the embodiment of the invention one is to the adaptation method schematic diagram of PRB.

Fig. 5 is the schematic diagram of distributing to certain user's symbol in the embodiment of the invention two in designated time length.

Fig. 6 and Fig. 7 are that the FEC code word that provides of the embodiment of the invention two is to the adaptation method schematic diagram of symbol.

Fig. 8 is the flow chart of the FEC code word method for synchronous that provides of the embodiment of the invention four.

Fig. 9 is OFDMA physical frame structural representation.

Figure 10 is the schematic diagram of MAP message.

Figure 11 and Figure 12 are the schematic diagrames of user's current period mode of PRB carrying FEC code word when not resetting the codeword boundary of FEC.

Figure 13 is the functional block diagram of the FEC code word synchro system that provides of the embodiment of the invention five.

Figure 14 is that a kind of mac frame of providing of the embodiment of the invention six is to the flow chart of the adaptation method of physical frame.

Figure 15 is that a kind of mac frame of providing of the embodiment of the invention seven is to the functional block diagram of the adaption system of physical frame.

Embodiment

In order to make purpose of the present invention, technical scheme and advantage clearer, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, is not intended to limit the present invention.

Embodiment one:

The Physical Resource Block of OFDMA system, i.e. two-dimentional time/frequency source block, being also referred to as PRB is as the minimum resource allocation granularity, each PRB can take one or more symbols (symbol) on time shaft, take one or more subcarriers at frequency axis.As shown in Figure 1, can be N+1 with the PRB number in the available band of OFDMA system, wherein N is natural number.

Suppose a designated time length, be i.e. the time cycle of agreement, in this designated time length, distribute to certain user PRB as shown in Figure 2, wherein the implication of PRB (i, j) is, i represents i chronomere, j is illustrated in i j PRB constantly, and wherein i and j are natural number.

See also Fig. 3, the FEC code word that the embodiment of the invention one provides comprises to the adaptation method of PRB: within the time cycle of agreement, first PRB that distributes to the user is that the original position of FEC code word begins to carry data, be not enough to carry a FEC code word if distribute to the remainder of last PRB of user, then this remainder is filled invalid data, wherein, described FEC code word adopts regular length.Such as the inadequate codeword size of PRB among Fig. 3 (4,3) remainder.

The time cycle of this agreement can be the dispatching cycle of MAP indication cycle, physical source distributing or the time cycle of system's agreement, such as one or more symbol.

See also Fig. 4, in FEC code word that the embodiment of the invention one provides in the adaptation method of PRB, in the time cycle of agreement, be not enough to carry a FEC code word if distribute to the remainder of last PRB of user, then can also be according to the length of this remainder, the FEC code word is adopted shortening FEC code word, to improve resource utilization.

Take the FEC code as the RS code as example, if system adopts the fixedly RS of code length (255,239) coding, the N among the RS (N, K) represents that the length behind this RS code coding is the N byte, and K is the length of the information byte in the N byte, and the N-K byte is check byte.Distribute to the remainder of last PRB of user in time cycle to agreement, if less than fixing FEC code length, code length that then can physical length is encoded.As remain 200 bytes, can adopt RS (200,184).

Because the FEC code word in the fec frame that the embodiment of the invention one provides adopts regular length, support code word number and system complexity thereby reduce system; In addition, because in the time cycle of agreement, be not enough to carry a FEC code word if distribute to the remainder of last PRB of user, then according to the length of this remainder, the FEC code word is adopted shortening FEC code word, code carries useful data thereby the remainder that makes last PRB adopts shortening FEC, has therefore improved resource utilization; In addition and since within the time cycle of agreement the original position of FEC code word with distribute to the aligned in position of first PRB of user, therefore do not need additionally to increase the indication of FEC border, receive the recovery that FEC when wrong can the cycle and set the border MAP occurring.

Embodiment two:

OFDM (Orthogonal frequency division multiplexing, OFDM) Physical Resource Block of system, be that symbol (symbol) is as the minimum resource allocation granularity, only have a frequency band that CU is all a moment.

Suppose a designated time length, be i.e. the time cycle of agreement, in this designated time length, distribute to certain user symbol as shown in Figure 5.

See also Fig. 6, the FEC code word that the embodiment of the invention two provides comprises to the adaptation method of symbol: within the time cycle of agreement, first symbol that distributes to the user is that the original position of FEC code word begins to carry data, be not enough to carry a FEC code word if distribute to the remainder of last symbol of user, then this remainder is filled invalid data, wherein, described FEC code word adopts regular length.Such as the inadequate codeword size of 4 remainders of symbol among Fig. 6.

See also Fig. 7, in FEC code word that the embodiment of the invention two provides in the adaptation method of symbol, in the time cycle of agreement, be not enough to carry a FEC code word if distribute to the remainder of last symbol of user, then can also be according to the length of this remainder, the FEC code word is adopted shortening FEC code word, to improve resource utilization.

Take the FEC code as the RS code as example, if system adopts the fixedly RS of code length (255,239) coding, the N among the RS (N, K) represents that the length behind this RS code coding is the N byte, and K is the length of the information byte in the N byte, and the N-K byte is check byte.Distribute to the remainder of last symbol of user in time cycle to agreement, if less than fixing FEC code length, code length that then can physical length is encoded.As remain 200 bytes, can adopt RS (200,184).

Because the FEC code word in the fec frame that the embodiment of the invention two provides adopts regular length, support code word number and system complexity thereby reduce system; In addition, because in the time cycle of agreement, be not enough to carry a FEC code word if distribute to the remainder of last symbol of user, then according to the length of this remainder, the FEC code word is adopted shortening FEC code word, code carries useful data thereby the remainder that makes last symbol adopts shortening FEC, has therefore improved resource utilization; In addition and since within the time cycle of agreement the original position of FEC code word with distribute to the aligned in position of first symbol of user, therefore do not need additionally to increase the indication of FEC border, receive the recovery that FEC when wrong can the cycle and set the border MAP occurring.

Embodiment three:

The FEC code word that the embodiment of the invention three provides comprises to the adaptation method of Physical Resource Block:

Within the time cycle of agreement, according to first Physical Resource Block of distributing to the user of the MAP administrative messag in current period indication current period or distribute to the processing mode of last Physical Resource Block of user.The time cycle of described agreement is the dispatching cycle of MAP indication cycle, physical source distributing or the time cycle of system's agreement.

Wherein, the processing mode of first Physical Resource Block of distributing to the user of indication current period comprises: indicate first Physical Resource Block codeword boundary of FEC of whether resetting, as the FEC border of resetting, then the FEC code word is aligned in first Physical Resource Block position, otherwise adopt the code word of regular length, namely in the code word of the regular length of the common carrying in front of the afterbody of upper one-period and current period.

Wherein, the processing mode of last Physical Resource Block of distributing to the user of indication current period is specially: the processing mode when indicating the remainder of last Physical Resource Block to be not enough to carry the FEC code word of a regular length, described processing mode comprises: this remainder is filled invalid data, the FEC code word is adopted the code word of a regular length of the common carrying in front of the afterbody that shortens FEC code word or upper one-period and current period according to the length of this remainder.Described shortening FEC code word is reed-solomon RS code word.

In the embodiment of the invention three, described Physical Resource Block is two-dimentional time/frequency source block (being PRB) in the OFDMA system or the symbol in the ofdm system.

Embodiment four:

See also Fig. 8, the FEC code word method for synchronous that the embodiment of the invention four provides may further comprise the steps:

S101, reception physical frame;

In the embodiment of the invention four, for the OFDMA frame, each physical frame comprises Np payload (payload) symbol, and TS (Training Sequence, training sequence) is used for frame and delimits and channel training, as shown in Figure 9.

S102, detect described physical frame, obtain frame synchronization;

In the embodiment of the invention four, for the OFDMA frame, detection be TS in the described physical frame.

The MAP message of S103, parsing broadcasting is determined the Physical Resource Block to each user assignment;

In the embodiment of the invention four, described Physical Resource Block is two-dimentional time/frequency source block (being PRB) in the OFDMA system or the symbol in the ofdm system.

In the embodiment of the invention four, as shown in figure 10, the administrative messag that comprises MAP may take definite PRB position, the bearing mode of MAP is exemplified below: front one or more PRB that take beginning symbol carry, and indicate the PRB resource allocation conditions of whole MAP cycle (one or more symbol).

S104, regular according to a preconcerted arrangement determines the mode that code word is delimited;

In the embodiment of the invention four, described treaty rule is: within the time cycle of agreement, first Physical Resource Block of this user is the original position of FEC code word.Therefore each cycle of receiving terminal border of FEC code word of can again aliging.

S105, extract the FEC code word by fixing code length from the Physical Resource Block that distributes, rule is correspondingly processed to the remainder of last Physical Resource Block of the time cycle of agreement according to a preconcerted arrangement.

For example, if treaty rule is the remainder of last Physical Resource Block of the time cycle of agreement is to fill invalid data, then abandon the data of the remainder carrying of described last Physical Resource Block, be to adopt to shorten coding mode if treaty rule is the remainder of last Physical Resource Block of the time cycle of agreement, then extract the code word of the remainder length of this last Physical Resource Block.

In the embodiment of the invention four, step S104, rule according to a preconcerted arrangement determines that the mode that code word is delimited also can be: by the MAP administrative messag indication current period codeword boundary of FEC of whether resetting.Time cycle take agreement equals the MAP indication cycle as example, has the specific bit territory indication current period codeword boundary of FEC of whether resetting in the MAP administrative messag.

If the MAP administrative messag is indicated this user's current period codeword boundary of FEC of not resetting, then mode such as Figure 11 and shown in Figure 12 of Physical Resource Block carrying FEC code word.According to shown in Figure 12, the FEC code word is striden the PRB carrying in two cycles, and the afterbody in previous cycle does not exist fills or shortening FEC code word.

According to a preconcerted arrangement rule among the step S105 to the remainder of last Physical Resource Block of the time cycle of agreement be correspondingly processed specifically also can for:

If the MAP administrative messag is indicated this user's current period codeword boundary of FEC of not resetting, then the FEC code word is striden the Physical Resource Block carrying in two cycles, for first Physical Resource Block of time cycle of the remainder of last Physical Resource Block of time cycle of last agreement and a rear agreement, continue by fixing code length extraction FEC code word.

The FEC code word method for synchronous that the embodiment of the invention four provides, because regular according to a preconcerted arrangement, determine the mode that code word is delimited, from the Physical Resource Block that distributes, extract the FEC code word by fixing code length, rule is correspondingly processed to the remainder of last Physical Resource Block of the time cycle of agreement according to a preconcerted arrangement, therefore do not need additionally to increase the indication of FEC border, the border is set in the recovery in FEC energy cycle when MAP reception mistake occurring.

Embodiment five:

See also Figure 13, the FEC code word synchro system that the embodiment of the invention five provides comprises: receiver module 11, detection module 12, parsing module 13, determination module 14 and extraction module 15.Wherein

Receiver module 11 is used for receiving physical frame;

In the embodiment of the invention five, for the OFDMA frame, each physical frame comprises Np payload (payload) symbol, and TS (Training Sequence, training sequence) is used for frame and delimits and channel training, as shown in Figure 9.

Detection module 12 obtains frame synchronization for detection of the physical frame that described receiver module 11 receives;

In the embodiment of the invention five, for the OFDMA frame, detection be TS in the described physical frame.

Parsing module 13 is used for resolving the MAP message of broadcasting, determines the Physical Resource Block to each user assignment;

In the embodiment of the invention five, described Physical Resource Block is two-dimentional time/frequency source block (being PRB) in the OFDMA system or the symbol in the ofdm system.

In the embodiment of the invention five, as shown in figure 10, the administrative messag that comprises MAP may take definite PRB position, the bearing mode of MAP is exemplified below: front one or more PRB that take beginning symbol carry, and indicate the PRB resource allocation conditions of whole MAP cycle (one or more symbol).

Determination module 14 is used for according to a preconcerted arrangement rule, determines the mode that code word is delimited;

In the embodiment of the invention five, described treaty rule is: within the time cycle of agreement, first Physical Resource Block of this user is the original position of FEC code word.Therefore each cycle of receiving terminal border of FEC code word of can again aliging.

Extraction module 15 is used for extracting the FEC code word from the Physical Resource Block that distributes by fixing code length, and rule is correspondingly processed to the remainder of last Physical Resource Block of time cycle of arranging according to a preconcerted arrangement.

In the embodiment of the invention five, determination module 14 specifically can also be for the codeword boundary of FEC of whether resetting by MAP administrative messag indication current period.Time cycle take agreement equals the MAP indication cycle as example, has the specific bit territory indication current period codeword boundary of FEC of whether resetting in the MAP administrative messag.

If the MAP administrative messag is indicated this user's current period codeword boundary of FEC of not resetting, then mode such as Figure 11 and shown in Figure 12 of Physical Resource Block carrying FEC code word.According to shown in Figure 12, the FEC code word is striden the Physical Resource Block carrying in two cycles, and the afterbody in previous cycle does not exist fills or shortening FEC code word.

Extraction module 15 according to a preconcerted arrangement rule to the remainder of last Physical Resource Block of the time cycle of agreement be correspondingly processed specifically also can for:

The FEC code word synchro system that the embodiment of the invention five provides, because regular according to a preconcerted arrangement, determine the mode that code word is delimited, from the Physical Resource Block that distributes, extract the FEC code word by fixing code length, rule is correspondingly processed to the remainder of last Physical Resource Block of the time cycle of agreement according to a preconcerted arrangement, therefore do not need additionally to increase the indication of FEC border, the border is set in the recovery in FEC energy cycle when MAP reception mistake occurring.

Embodiment six:

See also Figure 14, a kind of mac frame that the embodiment of the invention six provides said method comprising the steps of to the adaptation method of physical frame:

S201, be that ethernet frame adds the frame separator, is specially:

Head at ethernet frame is placed a S symbol;

When without follow-up ethernet frame, the idle bit position is filled into Physical Resource Block; Namely place first a T symbol at the afterbody of a upper ethernet frame, represent the follow-up idle filling that is with the T symbol;

In the embodiment of the invention six, described Physical Resource Block is two-dimentional time/frequency source block (being PRB) in the OFDMA system or the symbol in the ofdm system.

S202, adopt 64/66B coding rule this ethernet frame of encoding; S203, the ethernet frame behind 64/66B coding is carried out the FEC coding and inserts check digit;

Be specially: for per 29 66B pieces carry out RS (255,239) coding, and insert the parity block of 2 66B pieces, as a FEC code word, i.e. 31 66B pieces;

S204, the frame behind the FEC coding is fitted to Physical Resource Block into user's appointment.

In the embodiment of the invention six, step S204 is specially:

Within the time cycle of agreement, first Physical Resource Block of distributing to the user is that the original position of FEC code word begins to carry data, be not enough to carry a FEC code word if distribute to the remainder of last Physical Resource Block of user, then this remainder is filled invalid data or according to the length of this remainder, the FEC code word is adopted shortening FEC code word, wherein, described FEC code word adopts regular length.

Take time cycle as MAP indication cycle of this agreement as example, frame behind the FEC coding, according to the Physical Resource Block number of current MAP period allocated to its carrying data, begin to carry frame behind the FEC coding from first physical resource block boundary wherein, if last Physical Resource Block is not enough to carry a FEC code word, then this remainder is filled invalid data, is not used in the frame after carrying FEC encodes.

Embodiment seven:

See also Figure 15, a kind of mac frame that the embodiment of the invention seven provides comprises to the described system of the adaption system of physical frame:

Add module 21, be used to ethernet frame to add the frame separator;

Coding module 22 be used for to adopt 64/66B coding rule this ethernet frame of encoding;

FEC coding module 23 is used for carrying out the FEC coding and inserts check digit;

Adaptation module 24 is for the Physical Resource Block that the frame behind the FEC coding is fitted to into user's appointment.

In the embodiment of the invention seven, described Physical Resource Block is two-dimentional time/frequency source block (being PRB) in the OFDMA system or the symbol in the ofdm system.

In the embodiment of the invention seven, add module and specifically comprise:

Placement module is used for placing a S symbol at the head of ethernet frame;

Packing module is used for when without follow-up ethernet frame, and the idle bit position is filled into Physical Resource Block; Namely place first a T symbol at the afterbody of a upper ethernet frame, represent the follow-up idle filling that is with the T symbol.

In the embodiment of the invention seven, adaptation module specifically was used within the time cycle of agreement, first Physical Resource Block of distributing to the user is that the original position of FEC code word begins to carry data, be not enough to carry a FEC code word if distribute to the remainder of last Physical Resource Block of user, then this remainder is filled invalid data or according to the length of this remainder, the FEC code word is adopted shortening FEC code word, and wherein, described FEC code word adopts regular length.

Among the said apparatus embodiment, included unit is just divided according to function logic, but is not limited to above-mentioned division, as long as can realize corresponding function; In addition, the concrete title of each functional unit also just for the ease of mutual differentiation, is not limited to protection scope of the present invention.

It will be understood by those skilled in the art that in the method that the embodiment of the invention provides that its all or part of step is to finish by the relevant hardware of program command.Such as finishing by computer runs programs.This program can be stored in read/write memory medium, for example, and random asccess memory, disk, CD etc.

Claims

1. a forward error correction mode FEC code word is characterized in that to the adaptation method of Physical Resource Block described method comprises:

Within the time cycle of agreement, first Physical Resource Block of distributing to the user is that the original position of FEC code word begins to carry data, be not enough to carry a FEC code word if distribute to the remainder of last Physical Resource Block of user, then this remainder is filled invalid data or according to the length of this remainder, the FEC code word is adopted shortening FEC code word, and described FEC code word adopts regular length.

2. the method for claim 1 is characterized in that, described Physical Resource Block is two-dimentional time/frequency source block in the OFDM access OFDMA system or the symbol symbol in the orthogonal frequency division multiplex OFDM system.

3. method as claimed in claim 1 or 2 is characterized in that, the time cycle of described agreement is the dispatching cycle of mapping MAP indication cycle, physical source distributing or the time cycle of system's agreement.

4. a forward error correction mode FEC code word is characterized in that to the adaptation method of Physical Resource Block described method comprises:

5. method as claimed in claim 4 is characterized in that, described Physical Resource Block is two-dimentional time/frequency source block in the OFDM access OFDMA system or the symbol symbol in the orthogonal frequency division multiplex OFDM system.

6. such as claim 4 or 5 described methods, it is characterized in that, the processing mode of first Physical Resource Block of distributing to the user of described indication current period comprises: indicate first Physical Resource Block codeword boundary of FEC of whether resetting, as the FEC border of resetting, then the FEC code word is aligned in first Physical Resource Block position, otherwise adopt the code word of regular length, namely in the code word of the regular length of the common carrying in front of the afterbody of upper one-period and current period.

7. such as claim 4 or 5 described methods, it is characterized in that, the processing mode of last Physical Resource Block of distributing to the user of described indication current period is specially: the processing mode when indicating the remainder of last Physical Resource Block to be not enough to carry the FEC code word of a regular length, described processing mode comprises: this remainder is filled invalid data, the FEC code word is adopted the code word of a regular length of the common carrying in front of the afterbody that shortens FEC code word or upper one-period and current period according to the length of this remainder.

8. such as claim 4 or 5 described methods, it is characterized in that the time cycle of described agreement is the dispatching cycle of MAP indication cycle, physical source distributing or the time cycle of system's agreement.

9. forward error correction mode FEC code word method for synchronous is characterized in that described method comprises:

Receive physical frame;

Detect described physical frame, obtain frame synchronization;

10. method as claimed in claim 9 is characterized in that, described Physical Resource Block is two-dimentional time/frequency source block in the OFDM access OFDMA system or the symbol symbol in the orthogonal frequency division multiplex OFDM system.

11., it is characterized in that described according to a preconcerted arrangement rule determines that the mode that code word is delimited is specially such as claim 9 or 10 described methods:

Within the time cycle of agreement, first Physical Resource Block of user is the original position of FEC code word.

12. method as claimed in claim 11 is characterized in that, the time cycle of described agreement is the dispatching cycle of MAP indication cycle, physical source distributing or the time cycle of system's agreement.

13., it is characterized in that described according to a preconcerted arrangement rule is correspondingly processed to the remainder of last Physical Resource Block of the time cycle of agreement and is specially such as claim 9 or 10 described methods:

If treaty rule is the remainder of last Physical Resource Block of the time cycle of agreement is to fill invalid data, then abandon the data of the remainder carrying of described last Physical Resource Block;

Be to adopt to shorten coding mode if treaty rule is the remainder of last Physical Resource Block of the time cycle of agreement, then extract the code word of the remainder length of this last Physical Resource Block.

14., it is characterized in that described according to a preconcerted arrangement rule determines that the mode that code word is delimited is specially such as claim 9 or 10 described methods: by the MAP administrative messag indication current period codeword boundary of FEC of whether resetting;

Described according to a preconcerted arrangement rule is correspondingly processed to the remainder of last Physical Resource Block of the time cycle of agreement and is specially:

15. a forward error correction mode FEC code word synchro system is characterized in that described system comprises:

Receiver module is used for receiving physical frame;

16. system as claimed in claim 15 is characterized in that, described Physical Resource Block is two-dimentional time/frequency source block in the OFDM access OFDMA system or the symbol symbol in the orthogonal frequency division multiplex OFDM system.

17. such as claim 15 or 16 described systems, it is characterized in that, described according to a preconcerted arrangement rule, determine that the mode that code word is delimited is specially: within the time cycle of agreement, first Physical Resource Block of user is the original position of FEC code word.

18. system as claimed in claim 17 is characterized in that, the time cycle of described agreement is the dispatching cycle of MAP indication cycle, physical source distributing or the time cycle of system's agreement.

19., it is characterized in that described according to a preconcerted arrangement rule is correspondingly processed to the remainder of last Physical Resource Block of the time cycle of agreement and is specially such as claim 15 or 16 described systems:

20., it is characterized in that described determination module is specifically for the codeword boundary of FEC of whether resetting by MAP administrative messag indication current period such as claim 15 or 16 described systems;

Described extraction module according to a preconcerted arrangement rule is correspondingly processed to the remainder of last Physical Resource Block of the time cycle of agreement and is specially: