WO2014176791A1

WO2014176791A1 - Method and device for multicarrier division multiplexing system

Info

Publication number: WO2014176791A1
Application number: PCT/CN2013/075154
Authority: WO
Inventors: 潘稻; 张晓风; 孙方林
Original assignee: 华为技术有限公司
Priority date: 2013-05-03
Filing date: 2013-05-03
Publication date: 2014-11-06
Also published as: CN104737480A; CN104737480B

Abstract

Provided are a method and device applied to a multicarrier division multiplexing system. The method comprises: obtaining a start time of an uplink grant from an optical line terminal of a time division multiplexing passive optical network system; according to a synchronization associated timestamp, determining a location of a multicarrier division multiplexing-based transmission unit corresponding to the start time of the uplink grant, wherein the multicarrier division multiplexing transmission unit is a symbol or a frame; and according to an average capacity parameter of time quantum, determining a resource block location corresponding to the start time, wherein the average capacity parameter indicates that the total capacity of the transmission unit is averaged to an integral number of time quanta contained in the transmission unit, and a time quantum unit indicates a time unit of the time division multiplexing passive optical network system.

Description

Method and device for multi-carrier division multiplexing system

The present invention relates to network communications, and in particular to a method and apparatus for a multi-carrier division multiplexing system. Background technique

In the past few decades, coaxial cable lines have been widely deployed around the world. One problem with traditional cable access is that it may not have a satisfactory data access solution that is sufficient for current or future user needs.

A Passive Optical Network (PON) uses an optical splitter to split a signal into multiple branches for transmission to individual users. Time Division Multiplexing (TDM) Passive optical networks enable multiple users to share wavelengths and provide an effective solution for fiber-to-the-home (FTTH).

Moreover, T-P0N can provide much higher data rates than coaxial cable systems. For example, an Ethernet PON (Ethernet P0N, EPON) can provide approximately 1 Gigabit per second (Gbps) uplink and downlink symmetric bandwidth to approximately 32 shared customers, while based on the ITU-T G.984 series of standards. Gigabit-Capable PON (GPON) supports 2.5 Gbps of downstream bandwidth and 1.25 Gbps of upstream bandwidth for approximately 32 shared customers. TDM P0 provides a variety of different packet processing capabilities, Quality of Service (QOS) functions and management features. However, these capabilities, features, and features can only be applied to pure fiber networks. Summary of the invention

The embodiments of the present invention provide a method and apparatus, which can solve the problem of resource mapping in a multi-carrier division multiplexing system.

In one aspect, a method for applying to a multi-carrier division multiplexing system is provided, including: obtaining a start time of an uplink grant from an optical line terminal of a time division multiplexed passive optical network system; Determining, according to the synchronization-related timestamp, a location of the multi-carrier division multiplexing-based transmission unit corresponding to the start time of the uplink grant, where the multi-carrier division multiplexing transmission unit is a symbol or a frame;

The resource block position corresponding to the start time is determined according to the average capacity parameter of the time quantum, wherein the average capacity parameter represents an average number of time quantum of the transmission unit averaged to the transmission unit, and the time quantum unit indicates time division multiplexing The unit of time of the source optical network system.

In another aspect, a network terminal component is provided for a multi-carrier division multiplexing system, including: a resource scheduler coupled to a physical layer module and a time division multiplexed passive optical network T-P0N protocol processing module, configured to The multi-carrier modulated resource control physical layer module performs multi-carrier transmission; the resource scheduler is configured to obtain, from the T-P0N protocol processing module, a start time of the uplink authorization of the optical line terminal of the T-P0N system, according to the synchronization-related timestamp Determining a location of the multi-carrier division multiplexing-based transmission unit corresponding to the start time of the uplink grant, and determining a resource block location corresponding to the start time according to the average capacity parameter of the time quantum;

Wherein, the transmission unit of the multi-carrier division multiplexing is a symbol or a frame;

Wherein, the average capacity parameter represents an average of the total capacity of the transmission unit to an integer number of time quantums included in the transmission unit, and the time quantum unit represents a unit of time of the TDM P0 system.

In another aspect, a system is provided that can include a network component and a converter unit component, a converter unit component for providing parameters of a modulation template for a network terminal and a carrier reordering table corresponding to the modulation template. Optionally, a converter unit component is configured to provide different modulation templates for a plurality of network terminal groups connected to a single optical line terminal, each network terminal group including one or more network terminals; Providing, for one or more network terminal groups of the plurality of network terminal groups, a carrier reordering table corresponding to the modulation template used by the one or more network terminal groups.

Optionally, a converter unit component is configured to provide an optical line terminal with an average rate or a quantum of time corresponding to a modulation template of the network terminal.

Optionally, the system further includes an optical line termination component, configured to generate uplink grant information, where the uplink grant information includes a start time of the uplink grant, where the uplink grant is based on an average rate of the modulation template or a capacity of the time quantum.

Based on the above technical solution, resource mapping and transmission in a multi-carrier sub-multiplexing system can be effectively solved The problem is that the Terry PON protocol is extended to the problem of resource allocation and service transmission in a multi-carrier system. The scheme resource mapping processing provided by the embodiment of the invention is simple, and the processing complexity of the heterogeneous system is effectively reduced. DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings to be used in the embodiments of the present invention will be briefly described below. It is obvious that the drawings described below are only some embodiments of the present invention, Those skilled in the art can also obtain other drawings based on these drawings without paying any creative work. Wherein, the same reference numerals denote the same parts.

1 is a schematic diagram of a hybrid system architecture in accordance with an embodiment of the present invention;

2 is a schematic diagram of a method for applying a multi-carrier division multiplexing system according to an embodiment of the present invention; FIG. 3A is a schematic diagram of symbol mapping according to an embodiment of the present invention;

FIG. 3B is a flowchart of symbol mapping according to an embodiment of the present invention; FIG.

4A is an example of a bit loading table provided by the present invention;

4B is an example of a carrier reordering bit loading table provided by the present invention; FIG. 5 is a schematic diagram of generating a carrier sequencing table according to an embodiment of the present invention;

6A is a schematic diagram of a bit loading distribution after carrier rearrangement according to an embodiment of the present invention; FIG. 6B is a schematic diagram of an average bit loading distribution after reordering according to an embodiment of the present invention; Generate intent;

FIG. 8 is a schematic diagram of a multi-carrier system according to an embodiment of the present invention;

9A is a schematic flowchart of a resource mapping method according to another embodiment of the present invention;

9B is a schematic diagram of resource mapping according to the present invention;

10A is a schematic flowchart of a configuration process of a multi-modulation template according to the present invention;

FIG. 10B is a block diagram showing the structure of a converter unit according to an embodiment of the present invention; FIG.

FIG. 11 is a schematic flowchart of a method on an 0LT according to an embodiment of the present disclosure;

FIG. 12 is a schematic flowchart of implementing an implementation on a network terminal according to an embodiment of the present invention; FIG. 13 is a structural block diagram of a system according to an embodiment of the present invention;

FIG. 14 is a schematic diagram of bit loading of a multi-modulation template according to an embodiment of the present invention; FIG.

15A is a schematic diagram of an authorization message according to an embodiment of the present invention;

FIG. 15B is a schematic diagram of a report message according to an embodiment of the present invention. detailed description

It will be understood that although illustrative embodiments of the various embodiments are provided below, any number of techniques, whether currently known or existing, may be used to implement the disclosed systems and/or methods. The present invention should in no way be limited to the illustrative embodiments, the drawings and the invention described below, including the exemplary embodiments and embodiments illustrated and described herein, but the scope of the appended claims Modifications within the full scope of the object.

In various embodiments of the invention, the TDM P0 protocol (e.g., for EP0N, GP0N, or other P0N protocols) may be extended to a multiple division multiplexing system. In this way, at least a part of the TDM P0 service is extended to the multi-carrier division multiplexing system, which can take advantage of the advantages of the T-P0 and multi-carrier division multiplexing systems. This method can be applied to a hybrid system of a TOM PON-based optical transmission system and a multi-carrier transmission scheme based multi-carrier transmission system. The multi-carrier transmission system may be an electric transmission system, such as a cable transmission system, or a radio frequency transmission system, and the TDM PON service is extended to such an electric transmission system, which can fully utilize existing electrical transmission resources and extend the distance of user terminal access. , providing high bandwidth for user terminals and effectively reducing access costs, and enabling TDM P0-based QoS to be flexibly extended to user terminals of the electrical transmission system. However, extending the TDM P0 service to electrical transmission is also challenging, such as uplink resource allocation or mapping. The uplink resource allocation or mapping will be described in detail below.

In some embodiments of the present invention, TLI P0N may be EP0N, or may be a TOM P0N supporting other rates and/or P0N protocols, such as GP0N, or 1 QG EP0N, or 1 QG GP0N (also known as xGP0N), or 1 0G. EP0N, or other known or subsequently developed TRIN P0N, or a combination of the above various T P0.

In some embodiments of the present invention, the multi-carrier division multiplexing system adopts two-dimensional resources in time domain and frequency domain. The source (represented by the available resource blocks) transmits a multi-carrier signal that includes an integer number of symbol durations in the time domain and a plurality of carriers in the frequency domain. Available multi-carrier division multiplexing schemes include: Orthogonal Frequency Division Multiplexing (OFDM), or Sub-Band Division Multiplexing (SLR), or Discrete Multi-Tone (DMT), or Discrete Wavelet Multi-Audio (Di screte Wavelet)

Multi-Tone, MT) schemes, or variants of various other OFDM or DMT schemes, etc. Carriers are also referred to as carriers, subchannels, subcarriers, or tones in a multi-carrier modulation system.

1 is a schematic diagram of a hybrid system architecture in accordance with an embodiment of the present invention. As shown in Fig. 1, a schematic diagram of an embodiment of a hybrid system 100 (hereinafter collectively referred to as system 100). The hybrid system 100 (hereinafter collectively referred to as the system 100) provides an operation of carrying TDMP0N services on a multi-carrier division multiplexing system, so that the TDM P0N services on the optical fibers are migrated to the multi-carrier division multiplexing system.

In the embodiment of the present invention, in the first transmission domain between the optical line terminal (OLT) and the converter unit, the frame or protocol data unit based on the TOM PON is in the form of an optical signal on the first transmission domain. transmission. For example, a TOM PON based frame or protocol data unit is transmitted between the 0LT 122 and the converter unit 124 via the optical fiber 123. A TDM P0 based frame or protocol data unit is transmitted between the OLT 122a and the converter unit 124a via the optical fiber 123a.

In some embodiments provided by the present invention, the second transmission domain and the first transmission domain between the converter unit and the network terminal (NT) employ different physical layers. In the second transmission domain, the TDM P0 based frame or protocol data unit is transmitted on the transmission medium of the second transmission domain in the form of a multicarrier signal. As shown in FIG. 1, between the converter unit 124 and the network terminal 128, a TDM P0 based frame or protocol data unit is transmitted via the cable 127. Between the converter unit 124a and the NT 128a, a TDM P0 based frame or protocol data unit is transmitted over the wireless medium 127a. The TDM P0N-based frame or protocol data unit may be any data unit or frame of the Tier P0 protocol stack layer 2 (ie, the T-Poly MAC layer). The second layer of the T-P0 protocol stack corresponds to the data link layer of the Open System Interconnection (OSI) model, where the data link layer Between the physical layer (layer 1) and the network layer (layer 3).

Converter unit 124 may perform the conversion of the first physical layer of the first transmission domain to the second physical layer of the second transmission domain, and vice versa. The TDM PON MAC layer functions can be implemented on the 0LT 122 and NT 128, including TDM P0NMAC layer framing, MAC control, Operation, Administration and Maintenance (0AM). The converter unit 124 can perform a forwarding operation that does not require identification processing for at least a portion of the TDM PON MAC layer.

In the embodiment shown in FIG. 1, the optical fiber 123 between 0LT 122 and the converter unit 124 may not include any optical splitter, the optical fiber 123 can reach a distance greater than 20 km P0N standard definition (km) ₀ For example, the optical fiber 123 The distance from the 0LT 122 carrying the TDM P0 signal to the converter unit 124 is approximately equal to 70 km or greater, and the supported logical NT 128 is approximately 32,768.

It should be understood that FIG. 1 is only one example of an embodiment of the present invention. In other examples, the optical fiber 123 between the 0LT 122 and the converter unit 124 may include one or more optical splitters (not shown), Combine and/or split between one and multiple optical signals. Specifically, the downstream optical signal optical power is divided into multiple signals to be supplied to the respective converter units 124, and the optical signals from the plurality of converter units 124 are multiplexed into one optical signal to be supplied to the 0LT 122. Optionally, one or more electrical splitters (not shown) may be included between the converter unit 124 and the NT 128 for splitting the downlink electrical signal into multiple signals for supplying the respective NT 128, and capable of The multiple uplink electrical signals are multiplexed into a single pass to the converter unit 124.

In the downlink direction, the first transmission domain and the second transmission domain are transmitted in a broadcast manner. Hosted

The protocol data unit or frame of the 0LT 122 to one or more of the NTs 128 (such as the downstream frames 5, 6, 7 of FIG. 1) is transmitted via the optical fiber 123 in a TDM manner. The converter unit 124 transmits the received frame or protocol data unit (downlink frames 5, 6, 7) via cable 127 in a multi-carrier division multiplexing (e.g., OFDM or Sili, etc.). Each NT 128 receives its own protocol data unit or frame via cable 127, such as NT (1) receiving its own downstream frame 6, NT (2) receiving its own downstream frame 5, NT (3) receiving its own Downstream frame 7. Specifically, the NT 128 can identify the downlink frame at the physical layer or the second layer MAC layer. E.g, In other embodiments of the present invention, the converter unit 124 transmits the downlink frame 5, 6, 7 in the physical layer using the same modulation mode and coding mode. Each NT may be based on the identifier in the frame (such as the logical link of EP0). Identification, or GP0N GP0N encapsulation method port identification (GP0N

Encapsulation Method Port Identifier, GEM port ID ) identifying the other or downstream frame ¹ J filtration own, not his own discard downlink frame. In other embodiments of the present invention, the plurality of NTs connected to the cable 127 correspond to different modulation modes and/or encoding modes, and the converter unit 124 uses the corresponding modulation modes and coding modes of the plurality of NTs to set the downlink frame 5 6, 7 performs processing operations, and multiple NT multi-carrier electrical signals are mixed and transmitted on the cable 127 by broadcasting; each NT can demodulate its own downlink frame. The protocol data unit or frame in the downlink direction may be a TOM PO-based protocol data unit or a frame, such as a T PON MAC frame. Correspondingly, the downlink frames 5, 6, 7 may be T PON MAC frames, such as EPON MAC frames or GPON MAC frames.

In the uplink direction, the plurality of NTs 128 may transmit respective data units or frames to the converter unit 124 via the cable 127 using frequency division multiple access (OFDM), such as Orthogonal Frequency Division Multiple Access (OFDMA). 1, the signal is transmitted to the converter unit 124 via the cable 127. The converter unit 124 transmits the protocol data unit or frame carried on the cable 127 to the OLT via the optical fiber 123 in the form of Time Division Multiple Access (TDMA). 122. Among them, 0FDMA is a multiple access technology based on OFDM, and is based on Teli's multiple access technology, which is widely studied and used in the industry, and will not be described again unless otherwise specified. Among them, the uplink data unit or frame in the uplink direction. It may be a TDM P0N-based protocol data unit or frame, such as a T PON MAC frame. In the system architecture, the transmission resources of the first transmission domain include time domain dimension transmission resources and do not include frequency domain dimension transmission resources, time domain dimensions. Transmission resources are measured by time window or time slot. 0LT to converter unit downlink direction is to T-picture multiple end users (association The data of the respective network terminal is broadcasted via the optical fiber medium, and the transmission resource allocation is not required in the downlink direction. The converter unit transmits the data of the plurality of end users via the optical fiber medium in the TOMA direction in the uplink direction of the OLT. To provide uplink transmission resource allocation to the NT, the uplink transmission resource allocation may be performed on the network terminal as a whole or on one or more logical channels on the network terminal. The transmission resource allocation of the second transmission domain includes time domain and frequency domain dimension allocation, and the time domain and frequency domain resources may be represented by resource blocks for characterizing the time and carrier (or subband) occupied by each transmission allocation. The 0FDMA mode is a resource block-based allocation unit, wherein the resource block is composed of M*N resource units, the resource unit may be one carrier, M represents the number of carriers, N represents the number of OF 丽 symbols, and N and M may be any integer.

Since the physical layer resource dimensions of the first transmission domain and the second transmission domain are different, it is complicated to integrate resources of two heterogeneous transmission domains in resource allocation. One solution is to perform segmentation grant and allocation between the 0LT 1 22 and the NT 1 28 as on the converter unit 1 24, ie the 0LT 1 22 allocates the uplink transmission resources of the first transmission domain to the converter unit 1 24, The converter unit 1 24 allocates the uplink transmission resources of the second transmission domain to the NT 1 28 connected under the converter unit 1 24 according to the authorization of the OLT 1 2 2 . Another solution is to allocate resources for NT 1 28 by 0LT 1 22.

A resource allocation and transmission method, and apparatus therefor, provided by some embodiments of the present invention, are applied to a hybrid system in which the NTT 28 is connected to the NT 1 28 through the converter unit 1 24 .

The embodiments of the present invention provide a method and apparatus for supporting a multi-carrier division multiplexing system supporting a T0 P0N service bearer, which involves one or more operation processes such as resource mapping, sending, and the like. The multi-carrier division multiplexing scheme adopted by the multi-carrier division multiplexing system may be based on, but not limited to, any one of the multi-carrier division multiplexing schemes mentioned above.

2 is a schematic diagram of a method for applying a multi-carrier division multiplexing system according to an embodiment of the present invention. The method relates to implementing a resource mapping process on a network terminal, where a TOM PON frame processing function can be implemented on a network terminal, and a TLT of TLI P0N is implemented. The point-to-multipoint communication is realized in the downlink, and the multi-point-to-point communication is realized in the uplink. The resource mapping process will be described below in conjunction with FIG. 1. The resource block involved in the following embodiment is a resource unit including N symbols and M carriers, where M is greater than or equal to 1, greater than or equal to 1.

Step S201: Obtain a start time of the uplink grant from the 0LT of the TDM P0 system.

Step S 2 03: Determine, according to the synchronization related timestamp, the location of the transmission unit of the multi-carrier division multiplexing system corresponding to the start time of the uplink grant, where the transmission unit may be a symbol or a frame. In an embodiment, the location of the transmission unit (ie, symbol or frame) may be determined based on the timestamp in the PON protocol frame in which the start time of the uplink grant is sent by the OLT 1 22, for example, the timestamp is used as the start of the uplink grant. The start position of the transmission unit (ie, symbol or frame) corresponding to the time, that is, the start time of the transmission unit (ie, symbol or frame).

In one aspect, the value of the superframe counter can be obtained from the GP0N protocol frame in which the authorization message is located. On the other hand, the timestamp can be carried in an authorization message, such as an EP0N authorization message. The timestamp may also be carried in the overhead of the downlink P0N protocol frame where the grant message is located. For example, the timestamp (the value of the superframe counter) is carried in the overhead of the downlink P0N protocol frame where the bandwidth grant message is located. The relevant content and format of the authorization message will be further described below, and will not be described herein.

In other embodiments, it may also be obtained based on a local timestamp on NT 1 2 8 .

Step S 205: Determine, according to an average capacity parameter of the TQ, a resource block location corresponding to a start time, where the average capacity parameter indicates that the total capacity of the modulation template is averaged to an integer number of TQs included in the transmission unit, and the TQ represents a time of the TDM P0N system. The unit.

In some embodiments, multiple resource blocks may be searched in a resource block list or a resource block sorting table (such as a carrier sorting table) in the order of the resource block list, and the capacity of the multiple resource blocks is matched with the capacity of the time domain interval. . Then, the resource block location corresponding to the start time of the uplink grant is determined according to the matching result. The capacity of the time domain interval herein may be based on the average capacity and the number of TQs included in the time domain interval, which is proportional to the length of the time domain interval. The time domain interval represents the time domain interval from the start time of the transmission unit to the start time of the uplink grant. Specifically, the operation of matching the capacity may be based on a bit capacity-related matching condition with the time domain interval, such as the capacity of the searched plurality of resource blocks being greater than or equal to the capacity of the time domain interval. In this way, the conflict between NT 1 28 and other NTs can be effectively avoided. In some embodiments of the present invention, the condition for the search success may be: the bit capacity of the searched plurality of resource blocks is greater than and close to the bit capacity of the time domain interval, such as just greater than the bit capacity of the time domain interval, that is, the searched A target resource block that satisfies the bit capacity condition that the bit capacity of the resource block is greater than or equal to the time domain interval. Here is a list of resource blocks (eg The carrier ordering table is arranged in the order of bit loading by resource blocks (such as carriers). The detailed matching process will be described in detail below with reference to examples.

Embodiments of the present invention provide various average capacity parameters. For example, the average capacity parameter may be an average bit capacity based on the total bit capacity corresponding to the modulation template and the number of units of the transmission unit (i.e., symbol or frame) that are quantum divided by time. The average bit capacity is proportional to the total bit capacity. As another example, the average capacity parameter may be an average number of carriers based on the number of carriers associated with the modulation template and the number of cells that the resource block is quantum divided by time.

The start time t _{Q of the} transmission unit (ie, symbol or frame) and the start time of the uplink grant are both in units (or units) of the time quantum (T ime Quant a , TQ ) of the TDM P0N system, expressed as an integer multiple of the length of the TQ. . The TQ has a fixed length as a time unit of the time stamp of the T-P0N system. TQ represents the time unit (or time unit;) of the Trine system, which is achieved by maintaining a local timestamp, which is based on the TQ count, plus one per TQ length. For example, both 0LT 1 22 and NT 1 28 can maintain a local timestamp, which uses a time counter that increments by 1 every 16 ns (ie, the length of TQ) (eg, an M-bit counter that counts in TQ length, M represents the number of bits in the counter) Provide a local timestamp. The length of the TQ is usually not equal to 1 second. It can take the length of time (in seconds) that the TDM P0 system transmits an integer number of bits as the length of the TQ. In one embodiment, the length of the TQ is the length of time (in seconds) at which the T-P0 system transmits an integer multiple of 8 bits, that is, the length of time (in seconds) that the T-P0N system transmits an integer number of bytes. . The specific value of the length of the TQ is related to each T-P0N. For example, in the EP0N system, the length of the TQ is 16 e_9 seconds (referred to as s) (ie, 16 nanoseconds, referred to as 16 n s for short).

Some embodiments of the present invention provide the length or end time of the uplink grant that the NTT 1 2 2 grants to the NT 1 28, and the NT 1 28 may use the length or the end time to determine the resource block location corresponding to the uplink grant, such as the occupied resource block. A number (such as the number of carriers), a resource block end position (such as the end carrier), and so on. The length or end time here is expressed in units of TQ and can be expressed as an integral multiple of the length of TQ.

In the embodiment of the present invention, any one or more of the start time length and the end time of the uplink grant may be carried in the authorization message sent by the OLT 1 22 to the NT 1 28, and the authorization is cancelled. The information can be an authorization message for any TDM PO. For example, the bandwidth mapping message of the GP0N or the Gate message of the EP0N, where the Gate message is a Protocol Data Unit (PDU) based on the Mul Upoint Control Protocol (MPCP), and the MPCPUD is an abbreviation of the MPCP PDU. .

The symbols included in the above transmission unit may include guard intervals. For example, the symbols include multi-carrier division multiplexing (e.g., OFDM) symbols and guard intervals. The length of the symbol is equal to the length of the multi-carrier division multiplexing (e.g., OFDM) symbol plus the length of the guard interval. The operation of increasing the guard interval can be implemented by adding a cyclic prefix and/or a cyclic suffix. The length of the OF symbol and the length of the guard interval can be set as needed. For example, the length of the OF symbol can be 20e-6s (that is, 20 microseconds, 20 s for short), and the length of the cyclic prefix is 1.248e_6s (that is, 1.248 μs), and the length of the symbol is 21.248e-6s. It can be understood that the selection and the manner of increasing the length of the guard interval can be referred to the existing solution, and will not be described again.

Embodiments of the present invention provide a modulation profile that describes modulation related parameters, including modulation parameters and coding parameters. The modulation parameter may include a modulation order or a bit load number, and the number of modulation bits corresponding to the quadrature amplitude modulation of the M constellation point as described below; the coding parameter may include a forward error correction coding (FEC) Corresponding parameters, coding parameters generally refer to the choice of these several codecs, which can be the codec identification. The embodiment of the invention provides that the system can provide multiple codecs with different code rates and different code block sizes. Wherein the code rate can be used to characterize the ratio of valid bits in the encoded data bits.

The modulation template in implementation specifically refers to the selection of modulation parameters and coding parameters corresponding to physical layer resources. In the OF modulation, the selection of the modulation order of each subcarrier, the selection of the coding and decoding parameters. The specific manner is related to the physical layer scheme. One method includes two parts. One is that different subcarriers correspond to different modulation orders, that is, a bit loading table, where the specific implementation may be consecutive (eg, 4) carriers. Use the same modulation order to reduce the amount of information that the transmitter and receiver need to interact with. Second, the coding parameters, select a codec for the modulation template, and determine the code rate and code block size after the codec is determined. Modulation template includes one bit loading The table and a certain codec; the other way is the Modu lati on and Cod ing Scheme, which defines a combination of a limited number of modulation modes and coding modes (ie, modulation and coding scheme levels). ), using a uniform modulation order and determined codec parameters in each level, in which the modulation template contains the modulation and coding scheme levels corresponding to each resource block, that is, there is a modulation and coding scheme level table and Each resource block corresponds.

A multi-modulation template means that several different modulation templates exist in the system and in the same network. The specific implementation is that each modulation template corresponds to different modulation parameters and/or coding parameters, such as a bit loading table and/or a codec. The parameters, or each modulation template, correspond to a different modulation and coding scheme rating table. The former in the following embodiments specifically introduces the implementation of the scheme.

The bit loading table describes a bit loading number of each of the plurality of carriers corresponding to the bit loading table, which represents the number of loading bits on the carrier, and the specific form may be the number of loading bits corresponding to the recording carrier index, such as carrier 1 corresponding to 10-bit loading, carrier 2 Corresponds to 12-bit loading and the like. The number of bit loadings corresponding to the M carriers is not completely the same, that is, the bit loading number corresponding to at least one part of the carriers is different from the bit loading number corresponding to the other part of the carriers. In addition, the embodiment further includes a carrier sequence table, where the carrier ordering table includes M carrier indexes (M is the total number of carriers or the total number of available carriers), and the mapping order of the bit stream to the carrier is performed according to the carrier ranking table. As shown in Table 1, the serial number in the table represents the order of bit stream to carrier mapping, and the corresponding carrier index is recorded on the right side of Table 1. As exemplified in Table 1, the bit stream is first mapped to carrier 2 and then to carriers 3, 1, and 4.

Table 1 Carrier Sorting Table

In a specific implementation, the related processing module may first obtain a carrier index according to a carrier ranking table. Then, according to the bit loading table, the number of bit loads corresponding to the relevant index is obtained, and constellation mapping, constellation demapping or log likelihood ratio calculation and subsequent processing are performed according to the number. In some embodiments of the present invention, the carrier ranking table is arranged according to the natural sequence of carriers, that is, from low frequency to high frequency order or high frequency to low frequency. For convenience of description, it is referred to as a first carrier ordering table. Embodiments of the present invention allow for multi-carrier division multiplexing modulation using a second carrier ordering table. Compared with the first carrier sorting table, the carrier sequence of the second carrier sorting table is different, and the number of bit loadings corresponding to the same carrier is the same (that is, the number of carrier loadings is unchanged). The mapping order of the bit stream to the carrier is performed according to the second carrier ordering table. The carrier order of the second carrier ordering table is based on the average bit capacity per carrier, and represents the average bit capacity corresponding to the number of carriers corresponding to the bit loading table, that is, the first carrier ranking table or other carrier ranking table according to the average bit capacity per carrier. Sort. In this way, it is possible to improve the adverse effects caused by the large randomness of the bit load distribution corresponding to the first carrier sequence table (ie, the order from low frequency to high frequency, or the order from high frequency to low frequency). The carrier reordering scheme may be performed based on the average bit capacity per carrier. For example, the carrier is reordered according to the condition or standard of the proximity of the bit loading number of the carrier to the average bit capacity per carrier, and the bit loading corresponding to the obtained second carrier table is obtained. The distribution is more uniform than the original one, which can effectively avoid the frequency domain overlap problem of users in different modulation template schemes with different modulation templates (including the same carrier). Hereinafter, the method of reordering the carrier and the operation procedure of applying the second carrier ranking table (ie, the reordered carrier ranking table) will be described in detail in conjunction with a specific example. The second carrier ordering table is also referred to as a carrier reordering table.

Multi-carrier division multiplexing (such as OF Li) modulation includes constellation mapping (or constellation coding) and frequency domain to time domain transform, wherein constellation mapping is used to map a bit stream to a carrier constellation point to output a frequency domain constellation symbol, frequency The domain-to-time domain transform transforms the output of the constellation map from the frequency domain to the time domain to output multi-carrier division multiplexing (eg, OFDM) symbols. The constellation mapping can adopt modulation and demodulation based on M Quadrature Amp Li tude Modu lati on (M-QAM), where M represents the number of constellation points, and M can take a power of 2, such as M=2n, n=2, 3, 4, ..., 10, 11, 12, ...). The more constellation points, the greater the amount of information that each symbol can transmit. It is also possible to use M Pha se-Shift Key ing based on M constellation points. M-PSK ), the same M can take a power of 2. Among them, the constellation points of M-QAM are more dispersed than the constellation points of M-PSK, and have better transmission performance. The frequency domain to time domain transform may be an Inverse Fast Fourier Transform (IFFT) or an Inverse Discrete Fourier Transform (IDFT). The corresponding receiving end can implement time domain to frequency domain transform by using Fast Fourier Transform (FFT) or Discrete Fourier Transform (DFT).

In some embodiments, the second carrier ordering table may be used to control the bit stream to constellation point mapping (or constellation coding), output frequency domain constellation symbols in the order of the second carrier ordering table, and perform frequency domain interleaving to restore back to the original Carrier order, ie the order from low frequency to high frequency, or from high frequency to low frequency order or frequency domain to time domain IFFT module (IFFT or IDFT). Wherein, the second carrier ordering table may, in other embodiments, control the order of the data bits of the bit stream into the constellation mapping by using the second carrier ordering table before the constellation mapping. The specific operation can refer to the existing carrier reordering scheme, and will not be described again.

It should be understood that other embodiments of the present invention provide for some additional processing at network terminal 128. For example, encoding before multi-carrier division multiplexing (such as OFDM) modulation, such as Cyclic Redundancy Check (CRC), Force Interference, Forward Error Correction (FEC), interleaving, etc. Or multiple combined encodings. After multi-carrier division multiplexing (such as OFDM) modulation, certain digital filtering operations can be performed. For specific implementation, reference may be made to existing solutions, and details are not described herein.

The symbol-based mapping will be described below with reference to Figs. 3A and 3B. FIG. 3A is a schematic diagram of symbol mapping in the embodiment of the present invention. FIG. 3B is a flowchart of symbol mapping according to an embodiment of the present invention. This embodiment is based on the average bit capacity of the TQ. A resource block is a resource unit containing 1 symbol and 1 carrier.

In step S301, the start time of the uplink grant is obtained from the TDM P0 system (ie, 0LT 122);

NT 128 can also obtain the end of uplink grant from the TDM PON system (ie 0LT 122) Between and/or length. The start time, length, and end time can all be obtained from the authorization message issued by the 0LT 122. As shown in FIG. 3A, the start time of the uplink grant is 1040, and the length L is 450, and the unit is TQ.

Step S303: Determine, according to the synchronization related timestamp, a location of a symbol of the multi-carrier division multiplexing system corresponding to a start time of the uplink grant;

NT 128 may be based on the timestamp and / or the OLT 122 related to the synchronization, symbols of determining a start time t _Q. NT 128 and the OLT 122 can be related to the synchronization timestamp consistent, and therefore, the start time may be determined according to the time stamp t _Q symbols supplied 0LT 122, the start time may be determined according to the time stamp t _Q symbol NT 128 can even The symbol start time t _{Q is} determined using the NT 128 local time stamp after the clock of the NT 128 is calibrated according to the time stamp of the 0LT 122.

In the case where there are a plurality of symbols, in addition to the first symbol, the start time of each subsequent symbol can be determined based on the start time of the previous symbol. The interval between two adjacent symbols is related to the number Ti of TQs divided by symbols, and may be a quantity Ti greater than or equal to TQ.

As shown in FIG. 3A, the symbol S includes an OF symbol and a cyclic prefix, and the length of the symbol S is assumed to be Ts in seconds. The length of the OFDM symbol is 20e-6s (ie 20 microseconds, abbreviated as 20 μ _δ ), and the length of the cyclic prefix is 1.248e-6s (ie 1.248 μ _δ ), then the length Ts of the symbol S is

21.248e-6s. The length of the TQ is 16e-9s. Thus, the symbol S contains the number of TQs

Ti=Ts/Ttq=21.248e-6/16e-9=1328 _o The start time of the first symbol is i ₀₀₀ . So assuming that the start time of a symbol is t _Q , the start time of the next symbol of the symbol is represented as t ₀ +Ti, so analogy.

In the embodiment of the present invention, the value of Ti may be calculated by the NT 128 itself or by the converter unit 124. Moreover, the NT 128 may save the Ti value locally for use in resource mapping, for example, the NT 128 may have a Ti value. Save to the modulation template.

It will be appreciated that the frequency domain start position of the symbol may not require positioning, depending on the modulation template. Step S305, determining, according to the average bit capacity of the TQ, a carrier position corresponding to the start time in the symbol, where the average bit capacity of the TQ is based on the total bit capacity of the symbol and the symbol is TQ The number of units of the division, representing the total bit capacity of the symbol averaged to each of the plurality of TQs divided by the symbol

On TQ. In the embodiment shown in Fig. 3A, a modulation template is described, and OF modulation parameters and coding parameters such as a bit loading table, a coding rate, and the like are described. The NT 128 can control the OFDM modulation operation using the OF modulation parameters in the modulation template. The bit loading table 12, 10, 8 and 6 in the bit loading table in FIG. 3A respectively correspond to 4 carrier index intervals 1 to 1024, 1025 to 2304, 2305 to 3200, 3201 to 4096, wherein 1 to 4096 represent carrier indexes, Identify the carrier. The carrier sequence for performing bit loading in Fig. 3A is from bottom to top.

In an embodiment of the present invention, the total bit capacity of the symbol may be determined according to the modulation template to be (. The total bit capacity c of one symbol of the modulation template description is based on the sum of the bit loading numbers of the carrier specified or specified by the modulation template. The total bit capacity C shown is expressed as:

C=12 X 1024+10 X 1280+8 x 896 + 8 x 896 = 37626(biis)

Then, the average bit capacity aq of the TQ shown in Fig. 3A is expressed as:

Aq=C/Ti=37632 /1328 = 2S337(bits)

It will be appreciated that the average bit capacity aq of the TQ can be calculated by the NT 128 as well as by the converter unit 124. Correspondingly, the NT 128 can save the average bit capacity aq of the TQ to the local, such as a modulation template for later use. In the case provided by converter unit 124, it may be based on a negotiation process between NT 128 and converter unit 124, which may occur during the NT 128 registration phase or training phase.

The start time of the uplink grant is 1040, and the start time of the symbol can be determined according to the average bit capacity aq of the TQ. The bit capacity of the time domain interval not allocated to the NT 128 before the start time is 40x28.337 = 1133. The length of the interval is proportional to the specific value, which can be determined according to the length of the time domain interval and the average bit capacity aq of the TQ. Since a uniform codec is selected for all carriers in the modulation template in this scheme, it is not necessary to consider the influence of the code rate of the coding and/or the code rate of the decoding when calculating the position. Modulation In the case of a coding scheme (or the case where multiple different codecs are used in other templates), resource blocks at different locations under one modulation template may use different codecs (different redundancy), in which case the above calculation may The corresponding position is calculated based on the transmitted payload. The change involved is that the actual transmission capacity based on the carrier is required instead of directly calculating the position according to the modulation order, and the carrier implementation transmission capacity is equal to the modulation order multiplied by the code rate of the codec corresponding to the carrier. It should be understood that determining the modulation template corresponding to the code rate based on the code rate and/or the decoded code rate may be applied to other embodiments of the present invention based on the average rate or the capacity of the TQ. Finding the target carrier position in the frequency domain according to the bit capacity of the time domain interval, so that the bit capacity of the carrier satisfies the bit condition related to the bit capacity of the time domain interval from the frequency domain start position of the symbol or frame to the frequency domain interval of the position of the target carrier. If yes, the starting carrier position of the uplink grant may be determined according to the location of the target carrier. The matching condition is: The bit capacity of the frequency domain interval is greater than or equal to the bit capacity of the time domain interval. Specifically, n carriers (the nth carrier is the target carrier) are found in the order of the carrier ordering table from the frequency domain of the symbol or the frame, so that the bit capacity of the n carriers is greater than or equal to the bit capacity of the time domain interval, The n + 1 carrier is determined as the starting carrier position of the uplink grant, that is, the carrier position corresponding to the start time of the uplink grant.

Referring to FIG. 3A, n carriers are sequentially searched from the beginning of the frequency domain (such as the start of the frequency domain of the symbol or frame) such that the bit capacity of the n carriers is greater than or equal to the bit capacity of the time domain interval. The next carrier of the target carrier may be determined as the location of the start carrier of the uplink grant, that is, the carrier corresponding to the uplink 4 authorized time ^.

Refer to Figure 3A for the bit capacity from the 1st carrier to the 95th carrier (ie the target carrier).

12 x 95=1 140 (bits) , which is just larger than the bit capacity of the time domain interval, that is, the first carrier that satisfies the carrier capacity condition that satisfies the carrier capacity of the frequency domain interval greater than or equal to the time domain interval. Then, the 96th carrier is determined as the carrier corresponding to the uplink grant time ^, that is, the start carrier of the uplink grant.

The embodiment of the invention also allows determining the number of carriers or ending carriers of the uplink grant according to the length of the target carrier and the uplink grant.

The time domain interval can be determined based on the average bit capacity aq bit capacity aq in units of TQ The bit capacity of the upstream grant. The bit capacity of the upstream grant is proportional to the length of the upstream grant. In the carrier ordering table, the starting carrier of the uplink grant (the 96th carrier shown in FIG. 3A) searches for a specific carrier as a starting position, and matches the starting capacity of the uplink grant with the bit capacity of the frequency domain interval of the specific carrier, and the matching The condition or standard for operating based on the bit capacity of the frequency domain interval greater than or equal to the bit capacity of the time domain interval

For example, the bit capacity of the time domain interval estimate of the uplink grant is determined according to the length 450 (TQ) of the uplink grant and the average bit capacity a q bit capacity aq in units of TQ:

Aq x L=28.337 x 450=12751.65 (bits)

In the carrier ordering table, starting from the 96th carrier, 1090 carriers are found. The carrier capacity of the m carriers is as follows:

929 x l2 + 161 x l0=12758(bits)

Correspondingly, a resource table of the uplink grant may be generated, including starting the carrier index and the number of carriers. This resource table can be used to control which carriers are allowed to load bits.

Similar to the symbols in FIGS. 3A and 3B, the resource mapping process of the frame and the resource mapping process of the symbol are basically the same, and the resource mapping process of the frame is briefly described below.

In an embodiment of the present invention, in a resource allocation (ie, resource block) N symbols (hereinafter referred to as the N symbols are frames), T 128 may acquire a timestamp corresponding to each frame to start the frame. That is the start time. The NT 128 can obtain the frame number corresponding to the start time of the uplink grant and the start time stamp t _Q corresponding to the frame according to the timestamp acquired from the OLT 122 and the total number of TQs T i corresponding to each frame. Here, the frame number is used to characterize the position of the frame. A frame here refers to a physical layer frame, such as an OFDM frame.

The NT 128 can determine the average bit capacity aq of the TQ based on the modulation template, similar to that mentioned above, and can be stored from the data stored on the NT 128, such as from a modulation template, or calculated from a bit loading table of the modulation template. For example, the bit capacity aq=C/T i corresponding to each TQ, that is, the average bit capacity of the TQ, is calculated according to the number of bits C that can be carried by one frame and the corresponding total number of TQs T i . The bit capacity of the time domain interval t _Q is determined according to the average bit capacity of the TQ, and the resource block position corresponding to the start time is searched for in the frame corresponding to the start time of the uplink grant. Specifically, the n resource blocks may be searched according to the frequency domain order, so that the total number of bits that the n resource blocks can carry is just greater than the above aq X (t _r t ₀ ), so that the n+th resource block in the frame is the start. The location of the resource corresponding to the time. Similarly, the total number of bits corresponding to the L TQs may be calculated according to the length L of the uplink grant, and m resource blocks are sequentially searched from the n+1 resource block, so that the total number of bits that can be carried by the m resource blocks is just greater than 1 X aq. . Then get the resource location of this authorization.

The carrier reordering will be described in detail below with reference to an example.

Carrier reordering refers to the reordering of the positions of the carriers, and the corresponding modulation template remains unchanged. Carrier reordering affects the mapping of bitstreams to carriers. Carrier reordering can be referred to as a frequency domain interleaving. The benefit of carrier reordering is to increase the resistance to narrowband noise. Because after carrier reordering, a group of carriers affected by narrowband interference are reordered, causing the distance of the affected carrier to increase, even being allocated to different terminals through resource allocation.

Fig. 4A shows an example of a bit loading table provided by the present invention. As shown in Fig. 4A, the order of the frequency domain of the vertical axis is referred to as a carrier ranking table. Generally, the default carrier ordering table is performed according to the order of low frequency to high frequency. As shown in the left side of FIG. 4A, the left side is the bit loading table corresponding to the original carrier ordering table. The bitstream-to-carrier mapping shown in Fig. 4A follows the pre-time domain post-frequency domain manner, and the data bits in the bitstream are sequentially loaded onto the carrier in carrier order. Carrier reordering refers to rearranging the order of carriers according to certain principles, so that the mapping order of bitstreams to carriers is performed according to new carrier ordering. The right side of FIG. 4A is a bit loading table corresponding to the carrier row list after carrier reordering. Before and after the carrier is sorted, the number of bit loadings corresponding to the same carrier is the same, except that the position of the carrier changes, and the order of the loaded data bits changes.

In the embodiment of the present invention, by reordering the carriers of the multi-carrier division multiplexing (such as the OF RI) symbol, the bit loading corresponding to the carrier can be uniformly distributed on the reordered frequency domain axis. As shown in FIG. 4A, the purpose of reordering is to evenly distribute the reordered bit loading on the frequency domain axis. In this way, arbitrarily fetching a number of carriers in the reordered frequency domain axis, The average number of carrier load bits will be approximated or equal to the average bit load of the carrier corresponding to the symbol. The more the number of carriers is taken, the closer the data is. An example of a carrier reordering bit loading table provided by the present invention is shown in FIG. 4B. As can be seen from the right side of FIG. 4B, the reordered bit loading table is uniformly distributed in the frequency domain, for example, the average bit loading per carrier of the frequency domain interval of the entire 4096 carriers is 9.1875 bits, and the reordered subcarriers from the starting subcarrier to the specific The average bit loading per carrier in the frequency domain interval of the subcarrier is 9, 9.33, 9, and is close to the average of the entire frequency domain interval.

The carrier reordering provided by the embodiment of the present invention is based on the average bit loading or capacity a per carrier, and based on the principle of bit loading average distribution in the rearrangement process, may be based on the average bit loading per carrier or the capacity a of the available subcarriers, so that the continuous The average bit loading per carrier in the frequency domain interval is equal to or approximating.

FIG. 5 is a schematic diagram of generating a carrier ranking table according to an embodiment of the present invention. The specific operation process is as follows: Step S501: Calculate an average bit load or capacity per carrier corresponding to the bit loading table a;

Step S503, selecting a first carrier to occupy a starting position of a new carrier ordering table (ie, a carrier reordering table);

Step S5Q5: Find a new carrier from the carrier ordering table, so that the new carrier is located in the next position of the new carrier sequence table, so that the average carrier bit loading number is equal to or closest to a;

In step S507, it is confirmed whether the sorting is completed. If not, step S505 is repeated, and if it is completed, the process proceeds to step S509.

Step S509: Output a new carrier ordering table (ie, a carrier reordering table) and its corresponding bit loading table. Thus, the bit loading on the new bit loading table is uniformly distributed.

The carrier ordering provided by the embodiment of the present invention needs to complete N-1 iterations, and N represents the total number of available carriers.

The following is a simple ma 11 a b code corresponding to the above algorithm.

Bi=[ones (1, 1024) *12, ones (1, 1280) *10, ones (1, 896) *8,

Ones (1, 896) *6]; % Orignal bit load table, initialize the bit loading table, that is, the bit loading table corresponding to the initial carrier ordering table B_ave=sum (bi) /length (bi);

Tt=zeros (1, 4096); % record carrier reordering table

Bi_p=zeros (1, 4096); % Record the corresponding bit loading table after reordering

% first tone keep the same

Tt (1)=1;

Bi_p(l)=12;

For i=2: 4096 r= :20;

Fwoorr jj==2: 4096

If bi (j)~=0

B_sum= (sum (bi _p) +bi (j) );

If (abs (b-sum/ i_b_ave) <r)

r=abs (b-sum/ i_b_ave);

Index= j;

End

11 (i) =index;

Bi_p (i) =bi (index);

Bi (index) = le9; % null out the carrier which has already been picked up

End

After the above processing, the U variable stores the reordered carrier ordering table, and the bi_p holds the bit loading table corresponding to the reordered carrier ordering table. FIG. 6A shows the carrier rearranged bit according to the embodiment of the present invention. Load distribution FIG. 6B is a schematic diagram showing the distribution of average bit loading after reordering according to an embodiment of the present invention. As can be seen from Fig. 6B, a correspondence diagram of the average bit load number and the number of carriers after reordering. The corresponding average bit condition per carrier. When the number of carriers increases, the resulting average bit loading number is approximately close to the carrier average bit loading number a corresponding to the full symbol.

FIG. 7 is a schematic diagram of generating a carrier ranking table according to another embodiment of the present invention.

Step S701, calculating an average bit loading or capacity a per carrier of the bit loading table;

Step S703, selecting the first carrier to occupy the starting position of the new carrier scheduling table;

Step S705: Calculate the average bit loading corresponding to the obtained new carrier ordering table. If it is greater than a (or less than a), a carrier is sequentially searched in the original sorting table, and the bit loading is less than a (or greater than a). Table

Step S707, confirm whether the sorting is completed, if not, repeat step S705, and if it is completed, proceed to step S709.

Step S709, outputting a new carrier ordering table and its corresponding bit loading table. Thus, the bit loading on the new bit loading table is uniformly distributed.

In the specific implementation, the carrier reordering may also be performed in a carrier group, that is, the carriers in the frequency domain are grouped according to a certain number (n, such as 4), the carrier reordering is reordered in units of carrier groups, and the order in the carrier group is maintained. constant. In the above method, the number of iterations is affected (N/n, N is the total number of available carriers, and n is the number of carriers in the carrier group); a carrier group is found in each iteration, its position is updated, and the carrier order in the carrier group remains unchanged. .

FIG. 8 is a schematic structural diagram of a multi-carrier system according to an embodiment of the present invention. The device 828 corresponds to the NT 128 or 128a shown in FIG. 1 and includes all or part of the functions of the NT 128 or 128a. Apparatus 824 corresponds to converter unit 124 or 124a shown in FIG. 1, and includes all or part of the functionality of converter unit 124 or 124a. A multi-carrier system supporting carrier reordering is provided in FIG. 8. It can be understood that, in other embodiments of the present invention, the carrier reordering function is unnecessary, for example, the same modulation stage is adopted for multiple carriers of multi-carrier modulation. The number of programs. As shown in FIG. 8, in the system provided by some embodiments of the present invention, the carrier reordering of the uplink direction, the transmitting end, and the receiving end of the apparatus 828 to the apparatus 824 is reversed. The carrier obtained by mapping the bit stream mapping from the transmitting end obtains the position in the original frequency domain according to the carrier ordering table (such as the input order of IFFT processing), and obtains the frequency domain to time domain transform (such as IFFT processing or class processing function). Corresponding time domain data; and the receiving end reorders the carriers obtained from the frequency domain to the time domain transform (such as FFT processing or class processing function) according to the carrier ordering table, and then performs constellation de-mapping to obtain the bit stream. In the following description, a carrier ordering table different from the input carrier order of the frequency domain to the time domain transform (e.g., IFFT processing) (e.g., the original frequency domain order) is referred to as a carrier reordering table.

As shown in FIG. 8 , at the transmitting end, the mapping module performs constellation mapping on the input bit stream according to the bit loading table corresponding to the carrier reordering table, and outputs the mapped carrier complex signal (ie, the frequency domain signal according to the carrier reordering table corresponding carrier order. ). The carrier reordering module is coupled to the mapping module, and may perform reverse operation on the mapped carrier complex signal according to a carrier reordering table (having a first carrier sequence), and transform the frequency domain into a time domain transform module (such as an IFFT module or The input carrier order of the IDFT module (ie, the second carrier sequence) is output. The input carrier sequence of the transform module may be a normal frequency domain order, such as a frequency domain from low to high or a frequency domain from high to low, or other order. The transform module performs frequency domain to time domain transform on the sorted complex signal to process the output time domain signal. The operation of sorting the signals in the carrier order may adopt a scheme of buffer output control. For details, refer to the existing scheme, and details are not described herein.

Correspondingly, the receiving end, the time domain transforming to the time domain transform module (such as the FFT module or the discrete Fourier module) performs time domain to frequency domain transform processing on the time domain signal to output a carrier complex signal (having a second carrier sequence), the carrier The reordering module rearranges the carrier complex signals (with the second carrier order) input by the transform module according to the carrier order of the carrier reordering table (ie, the first carrier order), and rearranges according to the bit loading table corresponding to the carrier reordering table. The subsequent carrier complex signal (having the first carrier sequence) is subjected to a demapping process to recover the bit stream. Wherein, the demapping process can calculate the result based on the bit decision result or the bit log likelihood ratio.

In other embodiments of the present invention, the carrier reordering operation at the transmitting end may be performed before the constellation mapping, that is, the carrier reordering module may be coupled to the mapping module input. Specifically, you can The input bit stream is rearranged according to a carrier reordering table (having a first carrier sequence) and a bit loading table, and the reordered bit sequence is subjected to a constellation of frequency domain to time domain transformed input carrier order (ie, second carrier order). Mapping to generate a carrier complex signal of the second carrier order. The time domain transform to time domain transform module performs frequency domain to time domain transform processing on the carrier sequence complex signal of the second carrier sequence to output the time domain signal. Correspondingly, at the receiving end, the signal received by the time domain transform to the frequency domain transform module (such as the FFT module) performs time domain to frequency domain transform to output the carrier complex signal of the second carrier sequence, and the demapping module converts the carrier complex signal. According to the second carrier order demapping process, the carrier reordering module rearranges the data bits according to the carrier order of the carrier reordering table (ie, the first carrier order) to recover the bit stream.

The processing in the downstream direction from the device 824 to the device 828 and the reverse processing in the above-described uplink processing are not described again.

The specific modules are divided as follows:

Upstream direction: The device 828 comprises: an encoder 8283u, a multi-carrier modulator 8282u and a transmitter 8281u. Apparatus 824 includes a receiver 8241u, a multi-carrier demodulator 8242u, and a decoder 8243u.

The encoder 8283u is used for encoding of the second physical layer, that is, encoding the second physical layer of the uplink protocol data unit or frame of the protocol processor 8283. The coding may satisfy the channel transmission requirements of the second physical layer, and the coding may include one or more of cyclic redundancy check, forward error correction, scrambling, time domain interleaving, and the like. The protocol processor 8283 is responsible for completing the processing of the protocol, implementing the MAC layer function, such as EP0N processing, or GP0N processing, or other TDM P0N protocol, or a combination of the above TDM P0N protocol processing.

A multi-carrier modulator 8282u for modulating a bitstream (from the encoder 8283u) onto a multi-carrier and outputting a multi-carrier time domain signal, which may employ various multi-carrier division multiplexing modulation techniques, such as OF, as mentioned herein. Lido carrier modulation. The resources available for multi-carrier modulation can be described or specified by the modulation template.

The multi-carrier modulator 8282u may include a mapping module, a frequency domain transform to a time domain transform module (such as the IFFT module of FIG. 8 or a similar processing module, such as an IDFT module). A mapping module, which can be used to implement constellation mapping, that is, mapping a bitstream to a constellation point to output a frequency domain symbol or signal. Implementation of the invention The multi-carrier modulator provided by the example supports the carrier reordering function, which can be implemented before the bit stream to constellation mapping or after the bit stream to constellation mapping. The functions and implementations of the carrier reordering module are described above and will not be described again. It should be understood that, in the embodiment of the present invention, the carrier reordering module is not necessary, for example, the carrier reordering module is not required when the output carrier sequence of the mapping module and the input carrier sequence of the I FFT module are consistent.

The receiver 8241u is configured to receive a multi-carrier signal, such as an OF picture multi-carrier signal. Receiver 8241 u may be a receiver that includes a radio frequency front end circuit.

The multi-carrier demodulator 8242u is configured to demodulate the received multi-carrier signal to recover the bit stream.

The decoder 8243u is configured to perform decoding of the second physical layer on the bit stream output by the multi-carrier demodulator 8242u, and has a decoding function corresponding to the transceiver encoder 8283u, such as descrambling, forward error correction decoding, etc. Multiple decoding.

On the receiving side of the first transmission domain (i.e., the P0N optical transmission domain) side, the apparatus 824 further includes an encoder 8244u and an optical transmitter 8245u. The encoder 8244u is used to implement the coding of the first physical layer, that is, the P0N physical layer coding, and the TOM PON may be any TDM PON involved herein, such as EP0N, or GP0N, or other TOM P0N. The optical transmitter 8245u transmits the bit stream encoded by the first physical layer to the 0LT 122 in the form of an optical signal.

In the downstream direction, device 824 includes: an optical receiver 8245d, a decoder 8244d, an encoder 8243d, a multi-carrier modulator 8242d, and a transmitter 8241d. Apparatus 828 includes a receiver 8281d, a multi-carrier demodulator 8282d, and a decoder 8283d.

On the side of the device 824, the optical receiver 8245d photoelectrically converts the optical signal of the optical signal of the first transmission domain (i.e., from the OLT 122) and outputs the first physical layer encoded bit stream in the form of an electrical signal. The decoder 8244d is configured to implement a decoding function of the first physical layer to output a bit stream of a protocol data unit or frame carrying the TDM P0N. The encoder 8243d is configured to implement a coding function of the second physical layer to output a second physical layer coded bit stream, and correspondingly, the second physical layer coded bit stream carries a protocol data unit or frame of the TDM P0N. The multicarrier modulator 8242 d modulates the received bit stream to a plurality of carriers to output a time domain multicarrier signal, and the multicarrier modulation employed is based on multicarrier resolution Use modulation, such as 0FDM. Transmitter 8241 d transmits the output time domain multi-carrier signal to the transmitter.

On the 8th side of the device 82, the receiver 82 8 1 d will receive a multi-carrier signal containing a second physical layer-encoded bit stream, and the second physical layer-encoded bit stream carries the protocol data unit or frame of the TDM P0N. The multi-carrier demodulator 8 282 d demodulates the multi-carrier signal from the receiver 828 1 d to recover the second physical layer-encoded bit stream. The decoder 828 3d is configured to perform a second physical layer decoding on the bitstream to recover the protocol data unit or frame of the TOM PON.

The multi-carrier modulation and demodulation in the uplink and downlink directions described above can be operated based on a modulation template. The resources available for multi-carrier modulation can be determined by the modulation template. The modulation template can be set with a carrier ordering table and a bit loading table. The bit loading table corresponds to a carrier reordering table. The carrier ordering table may be a carrier ordering table of a normal frequency domain order, or may be a carrier reordering table of carrier reordering. The modulation template can set the modulation and coding scheme, such as the modulation method, coding parameters, modulation order, etc. used.

The modulation template can be separately configured on the device 828 and the device 824 for implementing the corresponding modulation and demodulation functions, and can perform operations such as selecting, creating, and updating the modulation template. Apparatus 828 may include a resource scheduler 8286 that may perform operations such as resource partitioning, allocation, and control of multi-carrier modulation, some or all of which may be based on a modulation template.

Resource scheduler 8286 may also be responsible for initiating a report request to 0LT 122 to request 0LT 1 22 to allocate transmission resources for device 828u. The resource scheduler 8286 may also be responsible for mapping the time domain resources to the multi-carrier modulated resource blocks (e.g., carriers) in response to the 0LT 122 transmission grant, based on the start time, length, or other parameters of the 0LT 1 22 uplink grant. The resource scheduler 8286 can operate using any of the resource mapping methods mentioned herein, including mapping of average capacity based on TQ and/or control of carrier reordering.

The resource scheduler 8286 may be responsible for negotiating with the converter unit 1 24, 0LT 122 for modulation template (ie, transmission grant) related parameters, including uplink transmission related capability information and/or channel parameter reporting, modulation template negotiation, and the like. For details, please refer to the other aspects of this article. It should be understood that the resource scheduler 8286 is not limited to one physically independent module or device, which may be further divided into logical multiple modules, which may be partially or completely distributed in existing modules, for example, some functions may be integrated into protocol processing. Some functions can be integrated into the multi-carrier modulator. Apparatus 824 can include a resource scheduler 8246 that can be responsible for functions such as allocation, negotiation, maintenance, and update of modulation template related parameters of device 828, generation (i.e., reordering) of a carrier ordering table, such as from device 1828u. The resource scheduler 8246 may send the parameters related to the modulation template to the OLT 122, and may be sent to the OLT 122 through the management protocol of the TOM PON, for example, through the multi-point control protocol of the EP0N or the optical network terminal management control interface protocol of the GP0N or The physical layer operation maintenance management protocol is sent to the 0LT 122. Modulation template related parameters include, but are not limited to: based on the average rate of the modulation template or the capacity of the TQ, the capacity of the TQ may be the average bit load of the TQ or the average number of carriers of the TQ.

Both the apparatus 824 and the apparatus 828 provided by the embodiments of the present invention may include a controller and a memory, such as controllers 8287, 8247, and memories 8288, 8248. In particular, the memories 8288, 8248 can be used to store parameters related to embodiments of the present invention, such as modulation templates, computer instructions, and the like.

Multiple modules or devices may be integrated in embodiments of the invention. In one example as shown in FIG. 8, on the side of the device 824, the optical receiver 8245d and the optical transmitter 8245u are integrated into an optical transceiver 8245, and the decoder 8244d and the encoder 8244u are integrated into a codec 8244, an encoder 8243d, and a decoder. The 8243u can be integrated into a codec 8243, the multi-carrier modulator 8242d and the multi-carrier demodulator 8242u can be integrated into a multi-carrier modem 8242, and the transmitter 824 Id and the receiver 8241 can become the transceiver 8241. On the side of the device 828, the receiver 8281d and the transmitter 8281u are integrated into a transceiver 8281, the multi-carrier demodulator 8282d and the multi-carrier modulator 8282u can be integrated into a multi-carrier modem 8282, and the decoder 8283d and the encoder 8283u can be integrated into a codec. 8283. It should be understood that FIG. 8 is merely an example of the present invention in which module combinations may be reorganized according to module and/or integration needs. In another embodiment of the present invention, a method for resource mapping is provided, which can be effectively simplified. The complexity of resource mapping, especially when the bit loading of the modulation template is evenly distributed or uniform, can achieve a good accuracy while simplifying the complexity. In one embodiment, the resource mapping method can be used in a scheme that employs carrier length ordering. In another embodiment, the same modulation order (or bit loading number) can be employed on the available carriers on the modulation template.

FIG. 9A is a schematic flowchart diagram of a resource mapping method according to another embodiment of the present invention.

In step 901, the NT 128 obtains the start time of the uplink grant from the TOM PON system. The operation of obtaining the start time of the uplink authorization in step 901 is similar to the steps S201 and S301, and details are not described herein again.

Step S 903: Determine, according to the synchronization related timestamp, the location of the symbol or frame of the multi-carrier division multiplexing system corresponding to the start time of the uplink grant.

The operation of determining the position of the symbol or the frame in step S903 is similar to the steps S203 and S303, and will not be described again.

In step 905, the NT 128 determines the resource location corresponding to the start time in the symbol or frame based on the average number of carriers of the TQ.

Referring to FIG. 9B, the support symbol or start time is t _Q , and the start time of the uplink grant is, the average number of carriers per TQ aq' = CV Ti, (C' is the total number of carriers in the symbol or the total number of resource blocks in the frame, Ti' For the symbol or frame corresponding to the total number of TQ), the corresponding resource location is ceii t xaq'^l, (ce il is the rounding operation, the unit is the resource block (such as carrier)); the length of the uplink grant L corresponds to the resource block (such as The number of carriers is _Ce il(Lx _a q'). As shown in FIG. 3A, the start time of the uplink grant indicated by the authorization message is 1040, the length is 450, and the symbol start time is 1000, and the carrier corresponding to the start time 1040 of the uplink grant is ceil (40×3.08)+l=125; The allocation of 450 TQs is that the starting position is carrier 125 and the number is _C eil (450 x 3.08) = 1388 carriers. Therefore, the mapping of the time domain resource obtained by the 0LT to the frequency domain resource includes the starting carrier and the number of carriers, where the number of carriers indicates the number of carriers on the carrier ranking table that the current uplink grant starts from the starting carrier. The bit loading table corresponding to the carrier ordering table is uniformly or relatively uniformly distributed in the frequency domain, for example, the average bit capacity per carrier of a certain frequency domain interval (ie, the average bit loading per carrier) and the bit loading table corresponding to the modulation template. The average bit loading parameters are close or equal, and a certain margin parameter can be used to indicate the degree of proximity. This implementation is simpler and more effective. Moreover, the bit capacity corresponding to the obtained resource is very close to the expected capacity.

FIG. 10A is a schematic diagram of a configuration process of a multi-modulation template according to the present invention

In step S1010, the converter unit 124 obtains information related to the NT 128, including the capability information and/or channel performance information reported by the NT 128. The information may be partially or completely reported by the NT 128 to the converter unit, and the partial information may be converted by the converter. The degree of monitoring and analysis of the received signal is obtained, for example, performance information such as crosstalk, signal to noise ratio, and bit error rate. The capability information may include one or more capability information such as a maximum transmission rate allowed by the NT 128, a supported modulation scheme, an encoding scheme, and the like.

In step S1012, the converter unit 124 determines parameters of one or more modulation templates in the multi-modulation template and the corresponding carrier reordering table based on the obtained information.

Converter unit 124 may determine parameters of one or more modulation templates in the multi-modulation template based on the obtained information, such as capability information and/or channel performance information. The determined parameters may include a bit loading table and/or encoding. Configure a multi-modulation template and calculate a carrier ordering table for multiple modulation templates. The operation details of determining the parameters of one or more modulation templates in the multi-modulation template based on the capability information and/or the channel performance information may refer to prior art, such as the operation processing of the bit allocation of the digital subscriber line or the OF picture system.

The converter unit 124 may calculate a carrier reordering table corresponding to the one or more modulation templates in the multi-modulation template, so that the bit loading corresponding to the carrier reordering table is uniformly distributed in the frequency domain corresponding to the carrier reordering table. Specifically, the carrier ordering table of each modulation template may be based on the average bit loading per carrier corresponding to the modulation template. For the specific operation process, refer to any manner mentioned herein, such as the manner shown in FIG. 5 or FIG. 7.

It should be understood that the one or more modulation templates may be selected according to requirements, for example, the channel performance related to the network terminal corresponding to one or some modulation templates changes, or the network terminal corresponding to one or some modulation templates is related. The ability to change and so on. Some or some of the modulation templates may not need to be updated if there is no change or change in capability information or channel information within the allowable range, and the parameters of the modulation template are not to be re-determined or updated. In other embodiments of the present invention, the converter unit 124 may parameterize all modulation templates included in the multi-modulation template and corresponding carriers. Reorder the table to determine. The determined parameters and carrier reordering table can be configured to the converter unit

124.

In step S1 014, converter unit 124 may transmit the average rate or the capacity of the TQ based on one or more modulation templates to 0LT 122. Specifically, the converter unit 124 can calculate the average rate of each template in the multi-modulation template or the capacity of the TQ. The average rate is obtained by the total bit capacity of the symbol or frame and the length of the symbol or frame described by the modulation template, such as the total bit capacity of the modulation template divided by the length of the symbol or frame. The calculation of the capacity of the TQ refers to any method of development referred to elsewhere in this document.

In step S1 016, the converter unit 124 transmits the parameters of one or more modulation templates and the carrier reordering table to the corresponding NT 128, which may be in a broadcast or unicast manner.

The capacity of the above TQ may be the average bit capacity of the TQ based on the modulation template, such as the average bit capacity of the TQ or the average number of carriers of the TQ. Here, the bit loading table allows the number of bit loadings on a part of the carrier in a frequency band to be 0. As shown in Fig. 14, the carrier bit loading in the 17-1 9 MHz, 32-40 MHz subband is 0. Therefore, changes to the bit loading table may result in a change in the total number of available carriers in the band. The range of the number of bit loadings on each carrier may be determined according to the performance of the channel and the length of the symbol or the frame. In the embodiment of the present invention, the range of the number of bit loadings on each carrier may be taken.

0-1 0, 0-1 2 or 0-20. The multi-modulation template may contain specific features. For details, refer to other related descriptions in this document, and details are not described herein.

The embodiments of the present invention provide a prescribed multi-modulation template as described in other sections herein.

FIG. 10B is a block diagram showing the structure of a converter unit according to an embodiment of the present invention. Subsystem 1 000 on the converter unit includes:

The information acquisition template 1 001 is configured to acquire NT 128 related information, including capability information reported by the NT 128 and/or channel performance information of the NT 128; the information acquisition template 001 is coupled to the receiver of the converter unit 124, and may be included in The receiver can also be accessed via the interface. The channel performance information may include a signal to noise ratio, a bit error rate, and the like.

The modulation management module 1 002 is configured to determine, according to the information obtained by the information acquisition template 1 001, parameters of one or more modulation templates in the multi-modulation template and a corresponding carrier reordering table. This operation can be performed in the following situations: Network terminal online initialization process, or network operation and maintenance process, or network When the terminal enters the working state and needs to be updated, etc.

The sending interface 1 003 is configured to send the parameters of the one or more modulation templates and the corresponding carrier reordering table to the corresponding NT. It can be broadcast or unicast.

The sending interface 1 004 is configured to send the average rate or the capacity of the TQ corresponding to one or more modulation templates to the 0LT 122. The transmit interface 1 004 can send the average rate of each of the one or more modulation templates or the capacity of the TQ to the 0LT 122.

The modulation management module 1 002 can calculate an average rate or a TQ capacity corresponding to one or more modulation templates.

The modulation management module 1 002 may determine a carrier reordering table based on the bit loading a per carrier. The specific rearrangement operation may employ any of the carrier reordering methods mentioned herein, as shown in Figure 5 or Figure 7.

The template manager can control the receiver of the converter unit 124 to receive the NT 128 OFDM signal using the reordered carrier ordering table.

The capacity of the above TQ may be the average bit capacity of the TQ based on the modulation template, such as the average bit capacity of the TQ or the average number of carriers of the TQ. The multi-modulation template may contain specific features. For details, refer to other related descriptions in this document, and details are not described herein.

FIG. 11 is a schematic flowchart of a method on an 0LT according to an embodiment of the present invention. The following description will be made with reference to Figs. 1 and 11.

In step S 1 1 1 0, the 0LT 122 receives the average rate or the capacity of the TQ corresponding to the modulation template. The average rate or the capacity of the TQ can be reported by the converter unit 1 24 .

The 0LT 122 may associate the average rate or the capacity of the TQ corresponding to the modulation template with information indicating a modulation template used by the NT 128 (such as a modulation template identifier), so that the corresponding information may be found according to the information indicating the modulation template used by the NT 128. Average rate or capacity of TQ.

Since a P0N port of the 0LT 122 (corresponding to an optical transceiver) can support a multi-template scheme, the LT 122 receives the average rate or TQ capacity corresponding to different modulation templates. The capacity of the TQ may be the average bit capacity of the TQ based on the modulation template, such as the average bit capacity of the TQ or the average number of carriers of the TQ.

Multi-modulation templates have the following characteristics: Multiple modulation templates contain multiple modulation templates, different modulations The template may correspond to the same available carrier resource, and the bit loading table is different. For example, the bit-loaded waves of different modulation templates have an isometric property, as shown in FIG. Multiple modulation templates include multiple modulation templates that are provided for use by multiple network terminal groups, each network terminal group containing one or more network terminals. Network terminals of the same network terminal group use the same modulation template. FIG. 14 is a schematic diagram of bit loading corresponding to two modulation templates according to an embodiment of the present invention. The two modulation templates may be respectively allocated to two network terminal groups, and each network terminal group uses a respective modulation template.

Specifically, in the multi-modulation template scheme, different groups are assigned different modulation templates, and the same group of network terminals are allowed to use the same modulation template. For example, a network terminal connected to a single 0LT port is divided into groups, including a first group and a second group. The first group comprises a plurality of network terminals employing a first modulation template; the second group comprises one or more network terminals, using a second modulation template different from the first modulation template. The modulation templates of the two groups include different channel capacities, such as modulation order or bit loading number.

The multi-template approach takes a compromise between a "broadcast" approach and a "unicast" approach. The so-called "broadcast" mode means that each network terminal in a system including multiple network terminals has its own independent modulation template, and the modulation template is used to send a signal to the transmitting end. The so-called "unicast" mode means: All network terminals in a system containing multiple network terminals use the same modulation template. The multi-template scheme can utilize the channel capacity of the network, because the channel conditions of different network terminals in the point-to-multipoint network are different, and the channel capacity of different network terminals is relatively high, so that the network terminal with high channel capacity can be used better. The channel requires a higher modulation template to provide an overall modulation rate, such as a modulation template that employs different bit loading schemes (e.g., higher modulation orders) and/or higher coding rates.

In step S1112, the OLT 122 receives the information reported by the NT 128 indicating the modulation template used by the NT 128. Specifically, the information may include a modulation template identifier, such as a modulation template used by the NT 128, or a modulation template number, or a modulation coding level, or other information capable of identifying a modulation template. The 0LT 122 can store information indicating the modulation template employed by the NT 128 locally. The information indicating the modulation template used by the NT 128 (such as a modulation template identifier) and the bandwidth allocation pair For example, a network channel as a whole or a logical channel or logical link on a network terminal. Specifically, the information indicating the modulation template used by the NT 128 (such as the modulation template identifier) and the identifier of the bandwidth allocation object may be associated, so that the bandwidth allocated to the bandwidth allocation object may be determined when the bandwidth allocation object is used. The logical link identifier of the modulation template finds the parameters of the modulation template. Step S1112 may be performed during the NT 128 initialization phase or during the entry phase. It should be understood that step S1112 is optional, that is, the 0LT may not need to know which modulation template is used by the NT 128.

In step S1114, the 0LT 122 receives the report message reported by the NT 128, allocates resources according to the average rate of the corresponding modulation template, and sends an authorization message. The report message and the authorization message are shown in Figures 15A and 15B, respectively.

FIG. 12 is a schematic flowchart of implementing an implementation on a network terminal according to an embodiment of the present invention. The operation will be described below with reference to Figs. 12 and 1.

In step S1 21 0, NT 128 determines the modulation template of NT 128 by communicating with converter unit 1 24 . The determining operation of the modulation template of NT 128 may employ any of the related operations mentioned herein. For example, NT 128 can obtain all or part of the parameters of the modulation template from converter unit 124. Before the NT 128 determines the modulation template, the NT 128 can report its own capability information and/or channel performance information monitored on the NT 1 28 to the converter unit 1 24, so that the converter unit 124 determines the appropriateness based on the information reported by the NT 128. Template. All or part of the parameters of the modulation template may be obtained from converter unit 124 during the NT 128 initialization phase, or may be obtained from converter unit 1 24 when NT 1 28 enters the operational phase. The parameters of the modulation template may include a carrier ordering table, which may be a carrier ordering table in a normal frequency domain order, or a carrier ordering table not in a normal frequency domain order (ie, a carrier reordering table as referred to herein). The parameters of the modulation template may include a bit loading table corresponding to the carrier ordering table. The modulation template can also contain other parameters.

Optionally, the parameters of the modulation template may be updated, for example, the carrier ordering table may be updated. The carrier reordering table may be based on the average capacity of the TQ of the modulation template, such as the average bit capacity of the TQ or the average number of carriers of the TQ. The average capacity of the TQ is related to the bit loading table.

In step S 1 21 2, NT 1 28 sends a report message to the OLT 122 requesting 0LT 1 22 as NT 128. Perform upstream authorization.

Optionally, the report message may include a bandwidth requirement, which may be in units of TQ, such as the number of TQs required for uplink transmission. In some embodiments of the invention, the bandwidth demand may be determined based on an average rate of the modulation template, the average rate being related to the bit loading table. Alternatively, the bandwidth demand can be based on the average rate and the number of bits waiting to be transmitted. The report message can carry multiple bandwidth requirements, each of which can be associated with a logical channel or logical link of the NT 128, and each logical channel or logical link can be represented by a corresponding identifier. It should be understood that in other embodiments of the present invention, the report message may not carry any bandwidth requirement. For example, the bandwidth requirement of the NT 128 may be estimated by the 0LT 122 based on local traffic monitoring.

Optionally, the report message may include a local time stamp of the NT 128 when the report message is sent. The optional local timestamp of NT 128 can be carried in the PON protocol data unit or frame in which the report message is located.

In step S1214, the NT 128 receives the authorization message of the OLT 122, and determines the time-frequency and the two-dimensional resource location of the multi-carrier modulation according to the uplink-authorized time domain one-dimensional resource indicated by the authorization message, where the time domain resource includes the uplink. The start time of the authorization, the determined two-dimensional resource location includes a frequency domain resource location corresponding to the start time of the uplink grant. The frequency domain resource location corresponding to the start time of the uplink grant may be determined based on the average capacity of the TQ of the modulation template, such as the average bit capacity of the TQ or the average number of carriers of the TQ. For the specific determination manner, refer to any method mentioned in this document, and no further description is provided. . The time domain start location of the two-dimensional resource location may be determined based on the synchronization related timestamp, such as based on a timestamp in the authorization message, or an NT 128 local timestamp. The two-dimensional resource may be allocated based on an integer number of symbols or a frame containing multiple symbols, allowing multiple network terminals to share the two-dimensional resources in a frequency division multiple access (eg, 0FDMA) manner.

In step S1216, the NT 128 modulates and transmits a signal at a two-dimensional resource location.

FIG. 13 is a structural block diagram of a system according to an embodiment of the present invention.

The NT 1328 is capable of establishing and maintaining a TDM PON MAC layer point-to-multipoint communication connection with the OLT 1322. The NT 1328 and the OLT 1322 provided by the embodiments of the present invention may correspond to the NT 128 and the OLT 122 respectively shown in FIG. 1, and may respectively include some or all of the functions of the NT 128 and the OLT 122. The OLT 1322 includes: an optical interface 13221, a physical layer module 13222, a PON protocol processing module 13224, and a resource scheduler 13226.

Optical interface 13221, which is the external interface of the 0LT 1322, is coupled to a converter unit connection that includes an electrical interface coupled to the NT 1328.

The physical layer module 13222 is configured to implement the first physical layer function. The first physical layer function may include the physical layer function of the physical layer TDM P0N. TOM PON can be any of the TOM P0N mentioned in this article.

The PON protocol processing module 13224, which supports the TDM PON protocol, is capable of generating a protocol data unit or frame of the TDM PO and transmitting it to the physical layer module 13222, and parsing the protocol data unit or frame of the TDM P0N from the physical layer module 13222. In one example, the P0N protocol processing module 13224 includes a PON MAC processor based on the TDM PON protocol, such as an EPON MAC processor, or a GPON MAC processor, or other TDM PON MAC processor.

The resource scheduler 13226 can allocate bandwidth to the NT 1328 and generate uplink authorized resource information according to the allocated bandwidth, and the uplink authorized resource information indicates a time domain one-dimensional resource. The resource scheduler 13226 can trigger the P0N protocol processing module 13224 to generate an authorization message based on the resource information.

The resource scheduler 13226 can allocate bandwidth to NT 1328 according to the parameters of the modulation template of the multi-carrier modulation, such as the average rate of the modulation template according to multi-carrier modulation or the average capacity of the TQ. The single optical interface of the 0LT 1322 (ie, a single P0N port) can support multiple sets of network terminal access using multiple template schemes. Therefore, a single optical interface can associate parameters of multiple modulation templates. The parameters of each modulation template can be provided by the converter unit, or directly or indirectly by NT 1328. The so-called indirect supply can be calculated according to the modulation template reported by NT 1328.

Optionally, the resource scheduler 13226 may obtain the bandwidth requirement reported by the NT 1328 from the P0N protocol processing module 13224. Optionally, the bandwidth requirement is related to a parameter of the modulation template, such as an average rate of the modulation template or an average capacity of the TQ. . Optionally, the resource scheduler 13226 can obtain the bandwidth requirement of the NT 1328 by a traffic monitor (not shown) on the 0LT 1322.

The resource scheduler 13226 can maintain parameters of the modulation template used by the network terminal for bandwidth allocation, and the parameters of the modulation template can be an average rate or an average capacity of the TQ, and a modulation mode. The network terminal associates with the network terminal identifier or the logical channel identifier or the logical link identifier as an index.

NT 1 32 8 includes: electrical interface 1 328 1. physical layer module 1 3282, P0N protocol processing module 1 32 84, resource scheduler 1 32 86.

Electrical interface 1 328 1, which is the external interface of NT 1 32 8 , is used to connect to the converter unit, which is connected to the optical interface with 0LT 1 32 2 .

The physical layer module 1 32 82 is used to implement the second physical layer function. The second physical layer function may include multi-carrier modulation and demodulation functions of the second physical layer in the receive direction. Multi-carrier modulation can be based on a modulation template, and multi-carrier demodulation can also be based on a modulation template. The modulation and demodulation templates can vary. The second physical layer function can send control and receive control, such as transmit and receive power control. The second physical layer function may also include channel coding and decoding functions. The decoding function may include one or more combinations of deinterleaving, descrambling, forward error correction decoding, cyclic redundancy solution checking, and the like. The decoding function may include one or more combinations of interleaving, scrambling, forward error correction coding, cyclic redundancy check, and the like.

The P0N protocol processing module 1 32 84, which supports the TDM P0N protocol, is capable of parsing protocol data units or frames from TLT P0 of 0LT 1 322 and generating protocol data units or frames of TDM P0. In one example, the P0N protocol processor 1 32 84 is a TDM P0N protocol based PON MAC processor, such as an EPON MAC processor, or a GPON MAC processor, or other TDM PON MAC processor.

The resource scheduler 1 32 86, may obtain the time domain one-dimensional resource indicating the uplink authorization from the P0N protocol processor 1 3284 as resource information, such as the start time and length of the uplink authorization, or the start time and the end time, or only the start time . The resource scheduler 1 3286 determines a time-frequency of the multi-carrier modulation and a two-dimensional resource location of the frequency domain according to the resource information, where the determined two-dimensional resource location includes a frequency domain resource location corresponding to a start time of the uplink grant. The frequency domain resource location corresponding to the start time of the uplink grant may be determined based on the average capacity of the TQ of the modulation template, such as the average bit capacity of the TQ or the average number of carriers of the TQ. For the specific determination manner, refer to any method mentioned in this document, and no further description is provided. . The time domain start position of the 2D resource location can be based on the synchronization related timestamp Determine, for example, based on a timestamp in the authorization message, or an NT 128 local timestamp. The two-dimensional resource may be allocated based on an integer number of symbols or a frame containing multiple symbols, allowing multiple network terminals to share the two-dimensional resources in a frequency division multiple access manner (eg, OF A). Resource scheduler 1 3286 can control multi-carrier modulation and transmission of physical layer module 1 3282 based on the determined two-dimensional resources.

The resource scheduler 1 3286 can determine the bandwidth demand and trigger the P0N protocol processing module 1 3284 to generate a report message. The bandwidth demand can be determined based on parameters of the modulation template, such as the average rate of the modulation template, which is related to the carrier loading table.

The resource information of the authorization message can be in units of T Q . The bandwidth demand indicated by the report message can be in TQ. Report message and authorization message

The report message of the embodiment of the present invention may include a status report of the NT 128. Optionally, the report message may indicate the bandwidth requirement of the NT 1 28, for example, the queue occupancy status of the NT 128, and may use the data waiting for the transmission in the queue. The quantity is expressed. The queue occupancy status may be for NT 1 28 as a whole or for a logical storage queue in NT 128, where the logical storage queue may be associated with a logical channel or a logical link, and each NT 128 is allowed to contain one or more logical channels or Logical links, associated with their respective logical storage queues. Optionally, the report message may include a local timestamp of the NT 128 when the report message is sent.

The report message may be a report message based on the TDM P0N protocol. For example, in the EP0N system, the report message is an EP0N-based report message, that is, a REPORT MPCPDU, and the _c- phase is, for example, in a GP0N system, the report message is a GP0N-based DBRu, where DBRu is an uplink dynamic bandwidth report ( Abbreviation for Ups t ream Dynami c Bandw i dt h Repor t ). In other TDM PON systems, the report message is based on the definition of the corresponding PON protocol and will not be described again.

The authorization message of the embodiment of the present invention is issued by the 0LT 122. The authorization message can be forwarded or transparently transmitted to the NT 128 via the converter unit 124, such as the converter unit 124 for physical layer conversion only.

The authorization message of the embodiment of the present invention may include one or more authorizations, and each authorization finger The position information of an uplink transmission window is shown. The location letter of each upstream transmission window may contain a start time. The location information may also include a length or an end time, where the start time and the end time may define the length of the uplink transmission window. Of course, if the 0LT 122 grants a fixed bandwidth grant to the NT 1 28, the grant message may not include a length or an end time. In other embodiments of the invention, the authorization message may even contain no time information for use as a ranging or hold link with the NT 128.

The authorization message included in the authorization message of some embodiments of the present invention may be not limited to one, and may include multiple transmission grants, each uplink transmission grant corresponding to one time domain location, and multiple uplink transmission grants do not conflict with each other. In the case of multiple authorizations, the authorization number can be included in the authorization message. According to some embodiments of the invention, each time domain location may be represented by a start time and length, or by a start time and an end time. In other embodiments of the invention, such as in a fixed bandwidth allocated application scenario, the time domain location may include a start time and no end time or length, as the length or end time of the transmission may be determined based on a known fixed bandwidth. The various times described above, such as start time, end time, and length, are measured in units of TQ.

The grant message of some embodiments of the present invention may include a timestamp indicating the local timestamp of 0LT 1 22 when the grant message was sent. The authorization message of other embodiments of the present invention may include a synchronization time indicating the time required for the 0LT receiver to synchronize, and the field indicating the synchronization time may be defined as a 2-byte (i.e., 16-bit) unsigned number.

The authorization message of some embodiments of the present invention may be an authorization message based on any one of the TDM PONs. For example, in a system in which the TDM P0N is an EP0N, the authorization message is an EP0N-based authorization message, that is, a Ga te message. FIG. 3 is an example of an authorization message provided by an embodiment of the present invention. The Ga te message in Figure 3 includes one or more grants, each of which indicates the start time and length. The Ga te message also includes a timestamp that characterizes the local timestamp of the 0LT when the Ga te message is sent. The timestamp is counted in units of time in TQ (ie, 16ns). As shown in FIG. 14A, the authorization message includes the following fields: source address, destination address, length/type, opcode, timestamp, number of authorizations, multiple authorizations (ie, multiple start time and length pairs), synchronization time, padding/ Reserved, frame Check the sequence. The length/type field value is 88-08, indicating that the IEEE 802. 3 frame is an MPC PDU frame; the opcode field value is 00-02, indicating that the frame is a Gate message. Specifically, the 0LT 122 or 122a and the NT 128 or 128a each have an M-bit counter (such as a 32-bit counter) that is incremented by 16 ns (time quantum), and the counter provides a local time stamp.

FIG. 15B is a schematic diagram of a reimbursement message according to an embodiment of the present invention. The report message indicates the amount of bandwidth request, which is in units of TQ. The report message includes the following fields: source address, destination address, length/type, opcode, timestamp, number of queues, multiple queue reports (queue #0 report, queue #1 report, queue #2 report queue #7 report) Fill

/Retention, frame check sequence. The length/type field value is 88-08, indicating that the IEEE 802. 3 frame is an MPCPDU frame; the opcode field value is 00-03, indicating that the frame is a report message. Specifically, 0LT 122 or 122a and NT 128 or 128a have an M-bit counter (e.g., a 32-bit counter) incremented by 16 ns (time quantum), which provides a local time stamp. Multiple Queue Reports (Queue #0 Report, Queue #1 Report, Queue #2 Report Queue #7 Report) Indicates the amount of bandwidth request for each queue based on the occupancy status of the queue, which is in TQ.

The embodiment of the present invention provides a network terminal component, which may include a resource scheduler of the network terminal, a resource scheduler 8286 as shown in FIG. 8, or a resource scheduler 13286 as shown in FIG. The specific functions of the resource scheduler of the network terminal are described above, and will not be described again. In other embodiments, the network termination component may include some or all of the protocol processing functions of TDM P0 and/or all or part of the TDM PON physical layer functions. For example, the protocol processing function of the TDM PON may include some or all of the TDM PON MAC functions. .

An embodiment of the present invention provides a converter unit component, which may include a resource scheduler of a converter unit, such as the resource scheduler 8246 shown in FIG. The specific functions of the resource scheduler of the converter unit are described above, and will not be described again. In other embodiments, the converter unit component may include the functionality of a physical layer of some or all of the multi-carrier modulation (e.g., OFDM modulation).

An embodiment of the present invention provides an optical line termination component, which may include a resource scheduler of an optical line terminal, such as the resource scheduler 13226 shown in FIG. The specific functions of the resource scheduler of the optical line termination component network terminal are described above, and are not described again. In other embodiments, The network termination component may contain some or all of the protocol processing functions of TDM P0 and/or all or part of the TDM P0 physical layer functionality. For example, the protocol processing functionality of TDM P0 includes some or all of the TDM PON MAC functionality.

The network terminal component, the converter unit component, and the optical line termination component of the present invention may all be based on an integrated chipset, such as a Field-Programmable Gate Array (FPGA), or an application specific integrated circuit (Appl. Integrated chipset for Integrated Circuit, ASIC).

It should be understood that, in a typical application of the method, device and system according to the embodiments of the present invention, the TDM P0 is EP0N, the second transmission domain is a coaxial transmission domain, and the OFDM modulation mode is adopted on the coaxial transmission domain. In other words, the first physical layer is the EP0N physical layer and the second physical layer is the coaxial physical layer. In this application scenario, the EP0N protocol is carried in the bit stream of the coaxial physical layer transmitted on the coaxial medium. In this paper, it is called EPO (EP0N Protocol over Coax), and its purpose is to introduce the mature EP0N technology and protocol. Coax or HFC network, extending IEEE EP0 transparently to Coax (Coaxial Cable) or HFC network (coax network or HFC network that may contain amplifiers is collectively referred to as coaxial domain), EPoC extends EP0N protocol To the coaxial domain, to achieve end-to-end management. Correspondingly, the 0LT (such as 0LT 122) mentioned in this paper can be replaced with the 0LT replacement based on EP0N. The converter unit (such as converter unit 124) can be replaced by Fiber Coax Unit (FCU), network. Terminals (such as T 128) can be replaced with Coax Network Units (CNU). The bit stream based on the second physical layer transmitted between the FCU and the CNU is an EPoC bit stream. The embodiments of the present invention provide various devices, each of which includes one or more processors, and is capable of executing a computer program for executing one of the above method flows, as shown in one of the method flows of FIGS. 3B, 7, 9A, 10A, 11, and 12. .

It should be understood that the "table" of the present invention may be a set of data elements (or values) organized in various forms, which are not limited to tables employing row and/or column models, which may be any set of related data. The data in the table can be physically stored in the database, and the data can be located in the storage area by means of pointers.

It should be understood that, in the embodiment of the present invention, the size of the sequence numbers of the foregoing processes does not mean The order of execution, the order of execution of each process should be determined by its function and internal logic, and should not be construed as limiting the implementation of the embodiments of the present invention.

In addition, the terms "system" and "network" are often used interchangeably herein. The term "and/or" in this context is merely an association describing the associated object, indicating that there can be three relationships, for example, A and / or B, which can mean: A exists separately, while A and B exist, exist alone B these three situations. In addition, the character " /" in this article generally means that the contextual object is an "or" relationship.

It should be understood that in the embodiment of the present invention, "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should be understood that determining B according to A does not mean that B is determined only on the basis of A, and that B can also be determined based on A and/or other information.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software or a combination of both, in order to clearly illustrate hardware and software. Interchangeability, the composition and steps of the various examples have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods for implementing the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present invention.

A person skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working process of the system, the device and the unit described above can refer to the corresponding process in the foregoing method embodiment, and details are not described herein again.

In the several embodiments provided herein, it should be understood that the disclosed systems, devices, and methods may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, or may be electrical, mechanical or otherwise. The form of the connection.

The units described as separate components may or may not be physically separate. The components displayed as units may or may not be physical units, i.e., may be located in one place, or may be distributed over multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the embodiments of the present invention.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a standalone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention contributes in essence or to the prior art, or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium. A number of instructions are included to cause a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The foregoing storage medium includes: a USB flash drive, a removable hard disk, a read-only memory (Read-Only Memory), a random access memory (RAM, Random Acce ss Memory), a magnetic disk or an optical disk, and the like, and the program code can be stored. Medium.

The above is only the specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any equivalent person can be easily conceived within the technical scope of the present invention. Modifications or substitutions are intended to be included within the scope of the invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

Rights request

1. A method applied to a multi-carrier wavelength division multiplexing system, characterized by comprising: obtaining the start time of the uplink authorization from the optical line terminal of the time division multiplexing passive optical network system; determining the uplink authorization according to the synchronization related timestamp The position of the transmission unit based on multi-carrier division multiplexing corresponding to the start time, and the multi-carrier division multiplexing transmission unit is a symbol or frame;

The resource block position corresponding to the start time is determined according to the average capacity parameter of the time quantum, where the average capacity parameter represents the total capacity of the transmission unit averaged to an integer number of time quanta contained in the transmission unit, and the time quantum unit represents time division multiplexing without The unit of time for the source optical network system.

2. The method according to claim 1, characterized in that the location of the transmission unit is determined based on the timestamp in the passive network protocol frame where the start time of the uplink authorization sent by the optical line terminal is located.

3. The method according to claim 1 or 2, characterized in that the process of determining the resource block position corresponding to the start time according to the average capacity parameter of the time quantum includes:

Search multiple resource blocks in order from the resource block list of the modulation template, and match the capacity of the multiple resource blocks with the capacity of the time domain interval, where the capacity of the time domain interval is based on the average capacity and the time included in the time domain interval Quantum number or length, where the time domain interval represents the time domain interval from the start time of the transmission unit to the start time of the uplink authorization;

The resource block location corresponding to the start time of the uplink authorization is determined based on the matching result.

4. The method according to claim 3, wherein determining the resource block position corresponding to the start time of the uplink authorization according to the matching result includes: when the capacity of the multiple resource blocks is greater than or equal to the capacity of the time domain interval, according to The locations of multiple resource blocks determine the location of the resource block corresponding to the start time of the uplink authorization.

5. The method according to any one of claims 1 to 4, characterized in that, the average capacity The parameter is the average bit capacity, which is based on the total bit capacity of the transmission unit and the number of units divided by time quanta of the transmission unit, indicating that the total bit capacity of the transmission unit is averaged to each time quanta of multiple time quanta divided by the transmission unit block. .

6. The method according to any one of claims 1 to 4, characterized in that the average capacity parameter is the average number of carriers, which is based on the number of carriers of the transmission unit and the number of units divided by time quanta of the transmission unit, indicating the transmission unit The total number of available carriers is averaged onto each of the multiple time quanta divided by the transmission unit.

7. The method according to claim 6, characterized in that the carrier sorting table corresponding to the modulation template has a first carrier order, and the first carrier order is not an order from low frequency to high frequency, nor is it from high frequency to high frequency. low frequency sequence.

8. The method of claim 1, wherein the first carrier sequence is based on the average bit capacity of each carrier, wherein the average bit capacity of each carrier represents the average of the total bit capacity corresponding to the bit loading table to the bit loading table The corresponding number of carriers.

9. The method according to any one of claims 1 to 8, characterized in that the resource block includes N symbols and M carriers, where N is an integer greater than or equal to 1, and M is an integer greater than or equal to 1. integer.

10. The method according to any one of claims 1 to 9, characterized in that,

The required time quantum number is calculated based on the average rate related to the modulation template, and the required time quantum number is reported to the optical line terminal.

11. A network terminal component applied to a multi-carrier wavelength division multiplexing system, characterized by comprising: a resource scheduler, coupled to the physical layer module and the time division multiplexing passive optical network T and PON protocol processing The management module is used to control the physical layer module for multi-carrier transmission according to the resource of multi-carrier modulation; the resource scheduler is used to obtain the start time of the uplink authorization of the optical line terminal of the T-PON system from the T-PON protocol processing module, Determine the location of the transmission unit based on multi-carrier multiplexing corresponding to the start time of the uplink grant based on the synchronization-related timestamp, and determine the location of the resource block corresponding to the start time based on the average capacity parameter of the time quantum;

Among them, the transmission unit of multi-carrier division multiplexing is a symbol or frame;

Among them, the average capacity parameter represents the average of the total capacity of the transmission unit to the integer time quanta contained in the transmission unit, and the time quantum unit represents the time unit of the TDM P0 system.

12. The network terminal component according to claim 11, characterized in that,

The resource scheduler obtains synchronization-related timestamps from the TDM PON protocol processing module.

13. The network terminal component according to claim 11 or 12, characterized in that the average capacity parameter includes the average bit capacity or the average number of carriers in the time quanta corresponding to the modulation template.

14. The network terminal component according to claim 11 or 12 or 13, characterized in that the modulation template corresponds to a carrier rearrangement table with a first carrier sequence, and the first carrier sequence is not a sequence from low frequency to high frequency. , nor the order from high frequency to low frequency; wherein, the first carrier table is based on the average bit capacity of the carrier, and the average bit capacity of the carrier represents the number of carriers corresponding to the total bit capacity corresponding to the bit loading table and the bit recording table.

15. A system, characterized by comprising: a resource scheduler as described in any one of claims 11 to 14; and

The converter unit component located in the converter unit is used to provide the network terminal with the parameters of the modulation template and the carrier reordering table corresponding to the modulation template.

16. The system according to claim 15, characterized in that the converter unit assembly is To provide different modulation templates for multiple network terminal groups connected to a single optical line terminal, each network terminal group containing one or more network terminals;

The converter unit component is used to provide one or more network terminal groups among the plurality of network terminal groups with a carrier reordering table corresponding to the modulation template used by the one or more network terminal groups.

17. The system according to claim 15 or 16, characterized in that,

The converter unit component is used to provide the optical line terminal with the average rate or time quantum capacity corresponding to the modulation template of the network terminal.

18. The system according to any one of claims 15 to 17, characterized in that it includes: an optical line terminal component located at an optical line terminal, used to generate uplink authorized information, wherein the uplink authorized information includes uplink authorized information. The start time. The uplink grant is based on the average rate or time quantum capacity corresponding to the modulation template.