A method for allocating resources in a centralized optical and wireless access network

Abstract

The present invention relates to the technical field of centralized optical and wireless access networks and discloses a resource allocation method in a centralized optical and wireless access network. The method only obtains cache status reports of delay-sensitive users that have successfully reported, and preferentially allocates optical and wireless resources to delay-sensitive users. When delay-sensitive users are prioritized, the expected number of RUs and the initial number of RUs of each TS user are calculated, the scheduled RUs are redistributed, and after obtaining the actual number of RUs of each TS user, the optical transmission rate and wireless transmission rate corresponding to each TS user are calculated. The present invention flexibly allocates RUs of different sizes and corresponding optical subcarriers to delay-sensitive users, accurately meeting the different needs of delay-sensitive users and greatly improving resource utilization.

Description

Technical Field

[0001] The present invention relates to the technical field of centralized optical and wireless access networks, and in particular to a resource allocation method in a centralized optical and wireless access network. Background Art

[0002] Broadband services in home networks place strict demands on high bandwidth and low latency. Currently, because a single access point (AP) cannot cover multiple rooms, Wi-Fi quality has become a significant factor limiting home broadband quality. Therefore, multi-AP networking is being used to improve network performance. Extending fiber to the room (FTTR) is the primary solution for achieving a gigabit experience throughout the home. The integration of passive optical networks (PON) and Wi-Fi is a key network technology for achieving FTTR. In FTTR scenarios, a centralized Wi-Fi access network (C-WAN) architecture enables centralized management and control, supporting collaboration between PON and Wi-Fi. In a C-WAN architecture, Orthogonal Frequency Division Multiplexing Passive Optical Network (OFDM-PON) is an effective solution for C-WAN fronthaul due to its moderate cost, flexible subcarrier granularity, and low latency. In the OFDM-PON-based C-WAN architecture, further research is needed to design a collaborative resource allocation mechanism for optical and Wi-Fi to meet the different broadband service requirements in FTTR scenarios.

[0003] The existing OFDM-PON-based C-WAN architecture uses a Wi-Fi access protocol for multi-user parallel transmission based on triggered frames. The protocol operates as follows: The main fiber unit (MFU) sends a trigger frame containing resource allocation information, including the number of radio resource units (RUs) for random contention and the transmission duration. After receiving the trigger frame and obtaining the relevant resource allocation information, the user (STA) randomly selects a RU through competition to transmit its data. When there are many competing users, collisions may occur, resulting in transmission failures.

[0004] The current OFDM-PON-based C-WAN protocol does not distinguish between service types. All types of users (STAs) in the same room's sub-fiber unit (SFU) compete for wireless resources. All allocated radio resource units (RUs) have the same size and duration, and data frames with shorter transmission times are padded with zeros. Figure 1The figure shows the internal synchronous transmission diagram of SFU. In addition, the current protocol and resource allocation scheme considers the complete synchronization between all rooms. To maintain synchronization between FTTR units (Sub Fiber Unit, SFU) in different rooms, it is also necessary to fill zeros on data frames with shorter transmission time. Figure 2 As shown in FIG, a schematic diagram of synchronous transmission between SFUs is shown; this results in a large waste of resources, and the time spent waiting for alignment also affects performance such as access delay and jitter.

[0005] In summary, in the OFDM-PON-based C-WAN architecture, the existing optical and wireless collaborative resource allocation algorithm does not differentiate between service priorities and cannot guarantee the TS requirements of delay-sensitive services. All users are allocated the same RU size, which cannot meet the network requirements of different service types. Within and between SFUs, a fully synchronized strategy is used, meaning all transmissions start and end at the same time. Maintaining synchronization requires zero-padding data frames with short transmission times to align transmission times, resulting in a huge waste of optical and wireless resources. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the problem in the prior art that service delay sensitivity is not taken into consideration and the same resources are allocated to all users, resulting in resource waste and transmission delay.

[0007] To solve the above technical problems, the present invention provides a resource allocation method in a centralized optical and wireless access network, which is applied to each room in the centralized optical and wireless access network, comprising:

[0008] Based on the cache status reports of successfully reported TS users, the bandwidth requirements of TS users in the room are obtained, the total wireless transmission capacity and total optical transmission capacity required by TS users in the room are calculated, and the wireless channel width of the room is obtained;

[0009] Based on the wireless channel width and the ratio of each TS user's bandwidth requirement to the total bandwidth requirement of the room, calculate the expected number of Schedule RUs for each TS user in the room.

[0010] Based on the expected number of RUs for each TS user and the number of wireless subcarriers in each Schedule RU, obtain the initial number of Schedule RUs allocated to each TS user in the room.

[0011] Based on the expected number of RUs and the initial number of RUs for each TS user, the scheduled RUs are reallocated to obtain the actual number of RUs for each TS user.

[0012] Based on the number of wireless subcarriers in each Scheduled RU, obtain the wireless transmission rate corresponding to the TS user;

[0013] Based on the actual number of RUs for each TS user and the number of radio subcarriers in each scheduled RU, the number of optical subcarriers required to transmit the data of each TS user is calculated. Combined with the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to each TS user is calculated.

[0014] Calculate the wireless transmission time and optical transmission time of each TS user based on the bandwidth requirements of each TS user and the wireless transmission rate and optical transmission rate corresponding to each TS user;

[0015] Resources are allocated based on the number of optical subcarriers, wireless transmission time, optical transmission time and preset Random RU transmission duration corresponding to each user.

[0016] Preferably, obtaining the cache status report of the TS user who successfully reported includes:

[0017] The MFU sends a buffer status report polling frame to request buffer status reports from all TS users;

[0018] After receiving the buffer status report polling frame, each TS user obtains the RU information that can be used for random contention access and uses the uplink OFDMA random access mechanism to randomly select an RU to upload the buffer status report:

[0019] If the RU is selected by only one TS user, the cache status report of the TS user is successful;

[0020] If the RU is selected by multiple TS users, the cache status reports of the multiple TS users that selected the RU fail to be reported.

[0021] Preferably, calculating the total wireless transmission capacity and the total optical transmission capacity required by TS users in the room and obtaining the wireless channel width of the room includes:

[0022] Based on the total number of supported users N in each room and the bandwidth requirements of the TS users in each room, the total wireless transmission capacity required by the TS users in each room is calculated as:

[0023]

[0024] Based on the total wireless transmission capacity required by TS users in all rooms, obtain the minimum available capacity to meet the needs of each room Expressed as:

[0025] Based on the minimum available capacity of all rooms As well as the total capacity of the OFDM passive optical network, calculate the total optical transmission capacity required by the TS users in each room Expressed as:

[0026]

[0027] Adjust the minimum available capacity to meet the needs of TS users in each room make

[0028] Based on the minimum available capacity to meet the TS user needs in each room The preset relationship table with the wireless channel width is used to obtain the wireless channel width B corresponding to the TS user in each room. i ;

[0029] in, represents the total wireless transmission capacity required by TS users in the i-th room, represents the bandwidth requirement of the jth TS user TS STA in the i-th room, T i ′ represents the data transmission time of the i-th room in the previous round; M represents the total number of rooms supported by the centralized optical and wireless access network.

[0030] Preferably, based on the wireless channel width and the ratio of the bandwidth requirement of each TS user to the total bandwidth requirement of the room, the expected number of Schedule RUs for each TS user in the room is calculated, expressed as:

[0031]

[0032] in, represents the expected number of RUs of the jth TS user TS STA in the i-th room, Indicates that the wireless channel width is B i The total number of RUs supported when represents the bandwidth requirement of the jth TS STA in the i-th room, and N represents the total number of users supported in each room.

[0033] Preferably, based on the expected number of RUs for each TS user and the number of wireless subcarriers in each Schedule RU, obtaining the initial number of Schedule RUs allocated to each TS user in the room includes:

[0034] Based on the expected number of RUs for the jth TS user in the i-th room Calculate the RU granularity value l of the jth TS user in the i-th room i,j , expressed as:

[0035] Calculate l of 2 i,j To get the initial RU number A allocated to the jth TS user in the i-th room i,j , expressed as:

[0036] Preferably, the scheduled RUs are reallocated based on the expected number of RUs and the initial number of RUs for each TS user, including:

[0037] Based on the wireless channel width and the initial number of RUs for each TS user, the total number of remaining RUs in the room is calculated as:

[0038] Calculate the difference between the expected number of RUs for each TS user and the initial number of RUs to obtain the number of RUs to be satisfied for each TS user, expressed as:

[0039] In each room, sort the number of RUs to be satisfied of all TS users in the room in descending order, and based on the sorted TS users, sort the number of RUs to be satisfied of the TS users in order. i,j The total number of remaining RUs in the room For comparison:

[0040] like Then allocate Scheduled RU to the TS user and update the total number of remaining RUs in the room;

[0041] like The demand of this TS user cannot be met, and the number of RUs to be satisfied for the next TS user is compared. i,j The total number of remaining RUs in the room

[0042] The scheduled RUs are redistributed until the total number of remaining RUs in the room reaches 0.

[0043] Preferably, based on the number of wireless subcarriers in each Scheduled RU, the wireless transmission rate corresponding to the TS user is obtained, which is expressed as:

[0044]

[0045] in, represents the wireless transmission rate of the jth TS user in the i-th room, N SS Indicates the number of spatial streams; A i,j represents the actual number of RUs allocated to the jth TS user in the i-th room, x represents the number of subcarriers contained in the RU, and A i,j*x represents the total number of subcarriers allocated to a TS user; N BPSCS,U Indicates the modulation order, R C Indicates the bit rate; T DFT Indicates the OFDM symbol length, T GI Indicates the symbol interval.

[0046] Preferably, based on the actual number of RUs for each TS user and the number of wireless subcarriers in each scheduled RU, the number of optical subcarriers required to transmit the data of each TS user is calculated. Combined with the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to each TS user is calculated, including:

[0047] Based on the actual number of RUs for each TS user and the number of radio subcarriers in each scheduled RU, the number of optical subcarriers required to transmit the data of each TS user is calculated as:

[0048]

[0049] Based on the number of optical subcarriers required to transmit the data of each TS user and the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to each TS user is calculated and expressed as:

[0050]

[0051] in, A represents the number of optical subcarriers required by the jth TS user in the i-th room, i,j represents the actual number of RUs allocated to the jth TS user in the i-th room, ρ represents the number of optical subcarriers required for the capacity provided by the wireless subcarrier of a scheduled RU, represents the optical transmission rate of the jth TS user in the i-th room, and r represents the transmission rate of a single optical subcarrier.

[0052] Preferably, obtaining the preset Random RU transmission duration includes:

[0053] After the scheduled RU allocation is completed, the number of RUs remaining in the channel is obtained as random RUs and allocated to TS users and NTS users who have not reported successfully.

[0054] Calculate the number of optical subcarriers, wireless transmission rate, and optical transmission rate required by each user corresponding to the Random RU;

[0055] Based on each user's bandwidth requirements and the corresponding wireless transmission rate and optical transmission rate, the wireless transmission time and optical transmission time of each user are calculated. Combined with the transmission time of frames in the network, the random RU transmission duration is obtained.

[0056] Preferably, calculating the number of optical subcarriers, wireless transmission rate, and optical transmission rate required by each user corresponding to the Random RU includes:

[0057] Calculate the number of Random RUs in the i-th room based on the wireless channel width and the maximum bandwidth of the wireless channel corresponding to the i-th room. Expressed as:

[0058]

[0059] Based on the total number of Random RUs in all rooms Calculate the total number of optical subcarriers used for scheduling access by comparing the number of optical subcarriers required for each RU capacity ρ Expressed as:

[0060] Based on the total number of Schedule RUs in all rooms Calculate the total number of optical subcarriers used for random access by comparing the number of optical subcarriers required for each RU capacity ρ Expressed as:

[0061] Compare whether the number of remaining photocarriers in an orthogonal frequency division multiplexing passive optical network, excluding the photocarriers used for scheduled access, meets the total number of photocarriers used for random access:

[0062] like The remaining optical subcarriers are allocated to users as needed;

[0063] like The remaining optical subcarriers are allocated to users in proportion; when allocating in proportion, the number of optical subcarriers allocated to each user is

[0064] Based on the number of radio subcarriers in each Schedule RU, the wireless transmission rate corresponding to the user is obtained. Based on the actual number of RUs for each user and the number of radio subcarriers in each Schedule RU, the number of optical subcarriers required to transmit the data of each user is calculated. Combined with the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to the user is calculated.

[0065] in, Indicates the total number of RUs supported when the wireless channel width is B; Indicates that the wireless channel width is B i The total number of RUs supported when M is used; M represents the total number of rooms supported in the centralized optical and wireless access network, and N represents the total number of users supported in each room; A i,j Indicates the actual number of RUs allocated to the jth TS user in the i-th room, represents the number of Random RUs used for random access in the i-th room; U represents the total number of subcarriers in the orthogonal frequency division multiplexing passive optical network.

[0066] Preferably, based on the bandwidth requirements of each user and the wireless transmission rate and optical transmission rate corresponding to each user, the wireless transmission time and optical transmission time of each user are calculated, and combined with the transmission time of the frame in the network, the RandomRU transmission duration is obtained, including:

[0067] Based on the bandwidth requirement of the jth TS user in the i-th room The corresponding wireless transmission rate Calculate the wireless transmission time of the jth TS user in the i-th room Expressed as:

[0068] Bandwidth requirement of the jth TS user in each i-th room The corresponding optical transmission rate Calculate the optical transmission time of the jth TS user in the i-th room Expressed as:

[0069] Based on the maximum wireless transmission time of all TS users in the i-th room Maximum optical transmission time and cache status report transmission time T BSR , trigger frame transmission time T TF , processing time T Process , Time required to confirm the frame T ACK Calculate the maximum transmission duration T using the short interframe space time SIFS. i , and use the maximum transmission time as the RandomRU transmission duration, expressed as:

[0070]

[0071] in,

[0072] Preferably, after obtaining the number of optical subcarriers, wireless transmission time, optical transmission time, and RandomRU transmission duration corresponding to each user, the method further includes:

[0073] In the same room, enable synchronous transmission between different users;

[0074] Between different rooms, during the transmission process of users with long transmission time, users with short transmission time are allowed to perform multiple rounds of transmission;

[0075] The transmission time T required for a new round of transmission by a user with short transmission time i ″, expressed as:

[0076] like A new round of transmission cannot be performed;

[0077] like A new round of transmission is then carried out and the maximum remaining time is updated

[0078] in, Indicates the maximum transmission time of the user, the expression is T i Indicates the maximum transmission duration.

[0079] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0080] The resource allocation method in a centralized optical and wireless access network described in the present invention only obtains cache status reports from delay-sensitive users that have successfully reported, and prioritizes the allocation of optical and wireless resources to delay-sensitive users. When delay-sensitive users are prioritized, RUs are initially allocated and reallocated based on the bandwidth requirements of each user, while matching optical subcarriers. By flexibly allocating RUs of different sizes and corresponding optical subcarriers to delay-sensitive users, the different needs of delay-sensitive users are accurately met, greatly improving resource utilization.

[0081] During the reporting phase, the present invention only allows delay-sensitive (TS) users to report cache status. By limiting the competition of non-delay-sensitive (NTS) users, the probability of successful reporting by delay-sensitive users is greatly improved, so that optical and wireless resources can be allocated to delay-sensitive users first in the future, effectively reducing the access delay of delay-sensitive users.

[0082] The present invention adopts a strategy of synchronization within a room and asynchrony between rooms. During the transmission process in a room with a long transmission time, multiple rounds of transmission are allowed in a room with a short transmission time, thereby reducing the resource waste caused by zero padding for synchronization alignment, effectively reducing the access delay and jitter of delay-sensitive services, and significantly improving resource utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0084] Figure 1 This is a schematic diagram of internal synchronous transmission in SFU;

[0085] Figure 2 Schematic diagram of synchronous transmission between SFUs;

[0086] Figure 3 It is a flowchart of the steps of the resource allocation method in the centralized optical and wireless access network provided by the present invention;

[0087] Figure 4 A flow chart of a priority-based access protocol for delay-sensitive services provided by the present invention;

[0088] Figure 5 Schematic diagram of the reporting process for TS users;

[0089] Figure 6 Schematic diagram of asynchrony between SFUs;

[0090] Figure 7 (a) is a schematic diagram showing the comparison of access delays between the present invention and the comparative solution. Figure 7 (b) is a schematic diagram showing the comparison results of access jitter between the present invention and the comparative solution. Figure 7 (c) is a schematic diagram showing the comparison results of wireless resource utilization between the present invention and the comparative solution. DETAILED DESCRIPTION

[0091] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0092] Reference Figure 3 As shown, the flowchart of the steps of the resource allocation method in the centralized optical and wireless access network provided by the present invention is applied to each room in the centralized optical and wireless access network, including:

[0093] S101: Based on the cache status report of the successfully reported TS user, the bandwidth requirements of the TS users in the room are obtained, the total wireless transmission capacity and the total optical transmission capacity required by the TS users in the room are calculated, and the wireless channel width of the room is obtained;

[0094] S102: Calculate the expected number of Schedule RUs for each TS user in the room based on the wireless channel width and the ratio of the bandwidth requirement of each TS user to the total bandwidth requirement of the room.

[0095] S103: Based on the expected number of RUs for each TS user and the number of wireless subcarriers in each Schedule RU, obtain the initial number of Schedule RUs allocated to each TS user in the room;

[0096] S104: Based on the expected number of RUs and the initial number of RUs for each TS user, the scheduled RUs are reallocated to obtain the actual number of RUs for each TS user.

[0097] S105: Based on the number of wireless subcarriers in each scheduled RU, obtain the wireless transmission rate corresponding to the TS user;

[0098] S106: Based on the actual number of RUs for each TS user and the number of radio subcarriers in each scheduled RU, the number of optical subcarriers required to transmit the data of each TS user is calculated. Combined with the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to each TS user is calculated.

[0099] S107: Calculate the wireless transmission time and optical transmission time of each TS user based on the bandwidth requirement of each TS user and the wireless transmission rate and optical transmission rate corresponding to each TS user;

[0100] S108: Perform resource allocation based on the number of optical subcarriers, wireless transmission time, optical transmission time, and preset Random RU transmission duration corresponding to each user.

[0101] Specifically, in step S101, obtaining the cache status report of the TS user that has successfully reported includes:

[0102] The MFU sends a buffer status report polling frame to request buffer status reports from all TS users;

[0103] After receiving the buffer status report polling frame, each TS user obtains the RU information that can be used for random contention access and uses the uplink OFDMA random access mechanism to randomly select an RU to upload the buffer status report:

[0104] If the RU is selected by only one TS user, the cache status report of the TS user is successful;

[0105] If the RU is selected by multiple TS users, the cache status reports of the multiple TS users that selected the RU fail to be reported.

[0106] During the reporting phase, the present invention only allows delay-sensitive (TS) users to report cache status. By limiting the competition of non-delay-sensitive (NTS) users, the probability of successful reporting by delay-sensitive users is greatly improved, so that optical and wireless resources can be allocated to delay-sensitive users first in the future, effectively reducing the access delay of delay-sensitive users.

[0107] Specifically, in step S101, the total wireless transmission capacity and the total optical transmission capacity required by the TS users in the room are calculated, and the wireless channel width of the room is obtained, including:

[0108] S101-1: Based on the total number N of users supported in each room and the bandwidth requirements of the TS users in each room, calculate the total wireless transmission capacity required by the TS users in each room, expressed as:

[0109]

[0110] S101-2: Based on the total wireless transmission capacity required by TS users in all rooms, obtain the minimum available capacity that meets the needs of each room Expressed as:

[0111] S101-3: Based on the minimum available capacity of all rooms As well as the total capacity of the OFDM passive optical network, calculate the total optical transmission capacity required by the TS users in each room Expressed as:

[0112]

[0113] S101-4: Adjust the minimum available capacity to meet the needs of TS users in each room make

[0114] S101-5: Based on the minimum available capacity to meet the needs of TS users in each room The preset relationship table with the wireless channel width is used to obtain the wireless channel width B corresponding to the TS user in each room. i ;

[0115] in, represents the total wireless transmission capacity required by TS users in the i-th room, represents the bandwidth requirement of the jth TS user TS STA in the i-th room, T i ′ represents the data transmission time of the i-th room in the previous round; M represents the total number of rooms supported by the centralized optical and wireless access network.

[0116] Specifically, in step S102, the expected number of Schedule RUs for each TS user in the room is calculated, which is expressed as:

[0117] in, represents the expected number of RUs of the jth TS user TS STA in the i-th room, Indicates that the wireless channel width is B i The total number of RUs supported when represents the bandwidth requirement of the jth TS STA in the i-th room, and N represents the total number of users supported in each room.

[0118] Specifically, in step S103, the initial number of Schedule RUs allocated to each TS user in the room is obtained, including:

[0119] Based on the expected number of RUs for the jth TS user in the i-th room Calculate the RU granularity value l of the jth TS user in the i-th room i,j , expressed as:

[0120] Calculate l of 2 i,j To get the initial RU number A allocated to the jth TS user in the i-th room i,j , expressed as:

[0121] Specifically, in step S104, the scheduled RUs are reallocated based on the expected number of RUs and the initial number of RUs for each TS user, including:

[0122] Based on the wireless channel width and the initial number of RUs for each TS user, the total number of remaining RUs in the room is calculated as:

[0123] Calculate the difference between the expected number of RUs for each TS user and the initial number of RUs to obtain the number of RUs to be satisfied for each TS user, expressed as:

[0124] In each room, sort the number of RUs to be satisfied of all TS users in the room in descending order, and based on the sorted TS users, sort the number of RUs to be satisfied of the TS users in order. i,jThe total number of remaining RUs in the room For comparison:

[0125] like Then allocate Scheduled RU to the TS user and update the total number of remaining RUs in the room;

[0126] like The demand of this TS user cannot be met, and the number of RUs to be satisfied for the next TS user is compared. i,j The total number of remaining RUs in the room

[0127] The scheduled RUs are redistributed until the total number of remaining RUs in the room reaches 0.

[0128] Specifically, in step S105, based on the number of wireless subcarriers in each Scheduled RU, the wireless transmission rate corresponding to the TS user is obtained, which is expressed as:

[0129]

[0130] in, represents the wireless transmission rate of the jth TS user in the i-th room, N SS Indicates the number of spatial streams; A i,j represents the actual number of RUs allocated to the jth TS user in the i-th room, x represents the number of subcarriers contained in the RU, and A i,j *x represents the total number of subcarriers allocated to a TS user; N BPSCS,U Indicates the modulation order, R C Indicates the bit rate; T DFT Indicates the OFDM symbol length, T GI Indicates the symbol interval.

[0131] Specifically, in step S106, calculating the optical transmission rate corresponding to each TS user includes:

[0132] Based on the actual number of RUs for each TS user and the number of radio subcarriers in each scheduled RU, the number of optical subcarriers required to transmit the data of each TS user is calculated as:

[0133]

[0134] Based on the number of optical subcarriers required to transmit the data of each TS user and the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to each TS user is calculated and expressed as:

[0135] in, A represents the number of optical subcarriers required by the jth TS user in the i-th room, i,j represents the actual number of RUs allocated to the jth TS user in the i-th room, ρ represents the number of optical subcarriers required for the capacity provided by the wireless subcarrier of a scheduled RU, represents the optical transmission rate of the jth TS user in the i-th room, and r represents the transmission rate of a single optical subcarrier.

[0136] In this embodiment, after allocating the scheduled RU, the following steps are also performed:

[0137] After the scheduled RU allocation is completed, the number of RUs remaining in the channel is obtained as random RUs and allocated to TS users and NTS users who have not reported successfully.

[0138] Calculate the number of optical subcarriers, wireless transmission rate, and optical transmission rate required by each user corresponding to the Random RU;

[0139] Based on each user's bandwidth requirements and the corresponding wireless transmission rate and optical transmission rate, the wireless transmission time and optical transmission time of each user are calculated. Combined with the transmission time of frames in the network, the random RU transmission duration is obtained.

[0140] Specifically, the number of optical subcarriers, wireless transmission rate, and optical transmission rate required by each user corresponding to the Random RU are calculated, including:

[0141] Calculate the number of Random RUs in the i-th room based on the wireless channel width and the maximum bandwidth of the wireless channel corresponding to the i-th room. Expressed as:

[0142] Based on the total number of Random RUs in all rooms Calculate the total number of optical subcarriers used for scheduling access by comparing the number of optical subcarriers required for each RU capacity ρ Expressed as:

[0143] Based on the total number of Schedule RUs in all rooms Calculate the total number of optical subcarriers used for random access by comparing the number of optical subcarriers required for each RU capacity ρ Expressed as:

[0144] Compare whether the number of remaining photocarriers in an orthogonal frequency division multiplexing passive optical network, excluding the photocarriers used for scheduled access, meets the total number of photocarriers used for random access:

[0145] like The remaining optical subcarriers are allocated to users as needed;

[0146] like The remaining optical subcarriers are allocated to users in proportion; when allocating in proportion, the number of optical subcarriers allocated to each user is

[0147] Based on the number of radio subcarriers in each Schedule RU, the wireless transmission rate corresponding to the user is obtained. Based on the actual number of RUs for each user and the number of radio subcarriers in each Schedule RU, the number of optical subcarriers required to transmit the data of each user is calculated. Combined with the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to the user is calculated.

[0148] in, Indicates the total number of RUs supported when the wireless channel width is B; Indicates that the wireless channel width is B i The total number of RUs supported when M is used; M represents the total number of rooms supported in the centralized optical and wireless access network, and N represents the total number of users supported in each room; A i,j Indicates the actual number of RUs allocated to the jth TS user in the i-th room, represents the number of Random RUs used for random access in the i-th room; U represents the total number of subcarriers in the orthogonal frequency division multiplexing passive optical network.

[0149] Specifically, obtain the Random RU transmission duration, including:

[0150] Based on the bandwidth requirement of the jth TS user in the i-th room The corresponding wireless transmission rate Calculate the wireless transmission time of the jth TS user in the i-th room Expressed as:

[0151] Bandwidth requirement of the jth TS user in each i-th room The corresponding optical transmission rate Calculate the optical transmission time of the jth TS user in the i-th room Expressed as:

[0152] Based on the maximum wireless transmission time of all TS users in the i-th room Maximum optical transmission time and cache status report transmission time T BSR , trigger frame transmission time T TF , processing time T Process , Time required to confirm the frame T ACK Calculate the maximum transmission duration T using the short interframe space time SIFS. i , and use the maximum transmission time as the RandomRU transmission duration, expressed as:

[0153]

[0154] in,

[0155] In this embodiment, after both Schedule RUs and Random RUs are allocated, the following steps are also included:

[0156] In the same room, enable synchronous transmission between different users;

[0157] Between different rooms, during the transmission process of users with long transmission time, users with short transmission time are allowed to perform multiple rounds of transmission;

[0158] The transmission time T required for a new round of transmission by a user with short transmission time i ″, expressed as:

[0159] like A new round of transmission cannot be performed;

[0160] like A new round of transmission is then carried out and the maximum remaining time is updated

[0161] in, Indicates the maximum transmission time of the user, the expression is T i Indicates the maximum transmission duration.

[0162] The present invention adopts a strategy of synchronization within a room and asynchrony between rooms. During the transmission process in a room with a long transmission time, multiple rounds of transmission are allowed in a room with a short transmission time, thereby reducing the resource waste caused by zero padding for synchronization alignment, effectively reducing the access delay and jitter of delay-sensitive services, and significantly improving resource utilization.

[0163] Based on the above embodiments, in an embodiment of the present invention, resource allocation is performed using the resource allocation method in a centralized optical and wireless access network proposed by the present invention, which can be specifically divided into two parts for explanation: one part is a priority-based access protocol for delay-sensitive services, which is used to obtain TS users who have reported successfully; the other part is a priority-based optical and wireless collaborative resource allocation algorithm.

[0164] 1. Priority-based access protocol for delay-sensitive services;

[0165] The embodiments of the present invention make the following modifications to the original Wi-Fi access protocol based on the buffer status report (BSR), including:

[0166] ① In a centralized C-WAN architecture, both the buffer status report poll (BSRP) and trigger frames (TF) contain information about the allocation of optical subcarrier resources and wireless RUs. Specifically, this information includes the size, number, and transmission time of the RUs used for designated access and random access, respectively, as well as the number of optical subcarriers and transmission duration required to match the data transmitted by the RUs.

[0167] During the reporting phase, the BSRP frame contains indication information. When a TS STA receives a BSRP, it responds by sending its Buffer Status Report (BSR) uplink. However, when an NTS STA receives a BSRP, it does not respond, does not participate in the reporting phase, and does not send a BSR uplink. During the reporting phase, only TS STAs are allowed to send their Buffer Status Reports (BSRs).

[0168] ③ During the data transmission phase, the media access control layer MAC at the master FTTR unit MFU allocates resources based on the information obtained during the reporting phase and saves the resource allocation results in the frame header of the TF trigger frame.

[0169] All radio resource units (RUs) are divided into two categories: RUs for scheduled access are assigned to specific TSSTAs and have varying sizes and transmission times based on the TSSTA's traffic requirements. RUs for random access have the same size and transmission time and are contested by users whose traffic requirements are unknown. Based on the allocation of radio RU resources, the number of required optical subcarrier resources and transmission time are calculated.

[0170] Based on the above modifications, refer to Figure 4 FIG. 1 is a flow chart of a priority-based access protocol for delay-sensitive services provided by the present invention, specifically including:

[0171] ①Reporting stage:

[0172] In the downlink direction, the Wi-Fi MAC in the MFU sends BSRP frames to request TS STAs to report their buffer status reports (BSPs). At this time, NTS STAs cannot compete with TS STAs for wireless resources, thereby increasing the probability of TS STAs successfully reporting their buffer status information.

[0173] In the uplink direction, when TS STAs receive BSRP frames, they obtain the RU information that can be used for random contention access and use the uplink OFDMA random access (UORA) mechanism to randomly select an RU to upload its buffer status information.

[0174] Reference Figure 5 The figure shows the TS user reporting process. When multiple TS STAs select the same RU to report status information, a collision occurs, resulting in reporting failure.

[0175] ②Data transmission stage:

[0176] In the downlink direction, the WiFi-MAC in the MFU allocates optical and wireless resources using a priority-based optical and wireless collaborative resource allocation algorithm based on the bandwidth request information of TS STAs collected during the reporting phase.

[0177] Among them, the Wi-Fi MAC in the MFU collects the BSR frames of TS STAs. The BSR frames contain information about the amount of buffered data, that is, the buffer size. The Wi-Fi MAC in the MFU can determine the bandwidth request status based on the buffer size.

[0178] Among them, the allocated wireless RU resources are divided into two categories, one is the RU for scheduled access (Scheduled RUs), and the other is the RU for random access (Random RUs); Scheduled RUs dynamically allocate RUs of different sizes to TS STAs that successfully compete in the reporting phase based on bandwidth request information. When allocating, they are specifically assigned to the corresponding TS STAs according to the instructions of the AID field in the TF, and no collision will occur. Random RUs are the remaining RUs except the RUs specifically used for scheduling. They are used for random access of users with unknown status information and may cause collisions. Among them, users with unknown status information include TS STAs that did not successfully compete in the first phase and did not report cache status information, as well as all NTS STAs.

[0179] Based on the RU allocation results, the WiFi-MAC in the MFU also allocates the corresponding number of optical subcarriers to each SFU and calculates the transmission duration for each. The results of the allocated optical and radio resources are stored in the TF trigger frame. When the TF trigger frame sent by the MFU MAC reaches the SFU, the SFU adjusts the subcarriers based on the optical subcarrier allocation information in the trigger frame header to facilitate subsequent uplink data transmission. When the TF trigger frame further reaches the user STA, different types of STAs select the corresponding RU for wireless segment data transmission based on the instructions in the trigger frame.

[0180] In the uplink direction, each STA's Wi-Fi physical layer data frame (Wi-Fi PHY frame) is transmitted in the assigned RU over the wireless segment. When the data frame reaches the SFU, it is first decapsulated into a Wi-Fi MAC frame. Then, it enters G.fin (the fiber-optic indoor communication network between the MFU and SFU) through the Ethernet access port. It is first encapsulated into a MAC frame at the MAC layer and then into a physical layer PHY frame. After that, it enters the OFDM-PON optical link for uplink transmission to the MFU. When the Wi-Fi MAC in the MFU successfully receives and parses the data sent by the user, it sends an ACK frame downlink.

[0181] 2. Priority-based optical and wireless collaborative resource allocation algorithm;

[0182] Based on the above embodiment, the embodiment of the present invention further provides a priority-based optical and wireless collaborative resource allocation algorithm. The Wi-Fi MAC in the MFU allocates optical and wireless resources to two types of users based on the buffer status information of some TS STAs obtained in the reporting phase, sets the corresponding transmission duration, and saves the allocation information in the trigger frame. The specific allocation process includes:

[0183] S201. Optical and wireless channel capacity selection for delay-sensitive services:

[0184] Wi-Fi 6 (802.11ax) supports multiple channel bandwidths to accommodate diverse network requirements. Choosing the appropriate channel width depends on a variety of factors, including the network's interference environment, bandwidth requirements, number of devices, traffic density, and the capacity of the fronthaul optical network.

[0185] Assume that M represents the number of SFUs in the room supported by the C-WAN architecture, and N represents the number of user STAs supported by the SFU in each room. According to the first reporting phase BSRP-BSR process, the bandwidth requirements of most TS STAs in each room can be obtained. Calculate the wireless transmission capacity for delay-sensitive services in each room Expressed as:

[0186] in, Indicates the traffic size requested by the jth TS STA in the i-th room, in bits; T i ′ represents the transmission time of the i-th room in the previous cycle.

[0187] Therefore, according to the wireless channel width table, the current SFU can be obtained. Minimum capacity required The corresponding wireless channel width B i ,Require

[0188] Then calculate the OFDM-PON transmission capacity required for each SFU The OFDM-PON optical resources in each room need to be able to carry the data transmitted by the wireless channel to avoid the situation where the SFU receives the data from the STAs and fails to transmit, loses packets and waits for retransmission due to insufficient optical capacity. When the wireless capacity requirements of all SFUs are not greater than the total OFDM-PON capacity C, the capacity requested by the wireless part Allocate optical capacity If it exceeds the limit, the light resources of each room will be allocated according to the proportion of traffic demand. Then adjust the wireless transmission capacity that can be carried by the optical capacity of each SFU Ensure that the optical subcarriers allocated in the current SFU can carry all the data transmitted wirelessly, that is, According to Table 1, the available wireless channel width B is obtained. i .

[0189] Among them, the OFDM-PON transmission capacity required by each SFU is Expressed as:

[0190]

[0191] in, represents the minimum capacity that meets the needs of the i-th room, and C represents the total capacity of OFDM-PON.

[0192] Table 1 Wireless channel bandwidth and peak rate under single antenna

[0193]

[0194] Through the above process, we can calculate the total optical and wireless capacity required by most TS STAs in each SFU to successfully transmit cache status information during the reporting phase.

[0195] S202, RU allocation on the Wi-Fi segment:

[0196] S202-1: Scheduled RU initial allocation;

[0197] In IEEE 802.11ax (Wi-Fi 6), different channel widths can support different numbers and granularities of RUs, including 26-tone RUs, 52-tone RUs, 106-tone RUs, 242-tone RUs, 484-tone RUs, and 996-tone RUs. For ease of calculation, when conditions such as the MCS remain the same, it can be roughly assumed that the transmission rate of a Wi-Fi segment is only related to RU size, and all RUs of different sizes can be considered as a combination of multiple 26-tone RUs. In particular, a large RU can be considered to be composed of two smaller RUs, so each RU granularity can be considered to be composed of a power of 2 of 26-tone RUs.

[0198] In the initial stage, the bandwidth request of TS STAs users is Perform initial allocation according to the ratio and calculate the number of 26-tone RUs that the j-th TS STAs user in the i-th room expects to be allocated Expressed as:

[0199] in, Indicates that the current room channel width is B i The total number of 26-tone RUs supported. Indicates the number of 26-tone RUs that the user expects to obtain. It may not meet the above RU specification requirements, so the calculation is less than or equal to The largest RU type that meets the specification requirements.

[0200] Assume that l represents the type of RU allocated to the user. l = 0 means that the RU type is 26-tone. Similarly, l = 5 means that the RU type is 996-tone. 5 26-tone RU. We can first calculate the number of RUs less than or equal to the number of RUs allocated to the jth user. Maximum RU type l i,j , thereby calculating the number of 26-tone RUs initially allocated A i,j , expressed as:

[0201] S202-2: Scheduled RU adjustment allocation:

[0202] After the initial allocation, if there are any remaining 26-tone RUs, the allocation results will be adjusted based on the size and number limit of each type of RU, and the allocation quantity of some users will be gradually increased to ensure the fullest possible utilization of unlimited resources.

[0203] First calculate the total number of remaining unallocated 26-tone RUs The difference D between the number of 26-tone RUs each user expects to receive and the number of 26-tone RUs initially allocated i,j , expressed as:

[0204]

[0205] In order to meet the Quality of Service (QoS) requirements of different users as much as possible, users with higher bandwidth requirements are given priority so that the number of resources allocated to them is closer to their expected number of resources. Therefore, the demand difference D i,j Sort in descending order; then adjust D i,j , put all TS STAs in front of NTS STAs in the allocation order, so that users with large bandwidth requirements in TS STA can be given priority. For the jth user who needs to continue allocation, calculate the number of 26-tone RUs it needs to further calculate as A i,j If the total number of remaining RUs is greater than the total number of required RUs, that is Then allocate as needed and adjust A i,i and Expressed as: A i,j =A i,j *2;

[0206] like If the remaining wireless resources cannot meet the needs of the current user, the system will continue to determine whether the needs of the next user can be met.

[0207] The above method can ultimately obtain the number of 26-tone RUs allocated to the scheduled access TS STAs, and can meet the RU number and position restrictions of different granularities.

[0208] S202-3: Random RUs allocation:

[0209] When the scheduled RUs for scheduled access are allocated, all the remaining RUs in the Wi-Fi channel are used for random access of all other users. Since the buffer status reports of all other users are not obtained, i th The number of all 26-tone RUs used for random access in the room, expressed as:

[0210]

[0211] Where B represents the maximum bandwidth of the wireless channel, B i Indicates the maximum bandwidth required by TSSTAs to successfully report cache status information in the first phase.

[0212] S203, OFDM-PON subcarrier allocation;

[0213] S203-1: For the scheduled RUs used for the specified allocation, the optical and wireless capacity selection for the TS STAs that successfully reported the buffer status information in step S201 ensures that the optical subcarriers are sufficient to transmit the data carried by the scheduled RUs. When the MCS setting is known, the wireless data transmission rate is also fixed, expressed as: Among them, N SS Indicates the number of spatial streams, N BPSCS,U Indicates the modulation order, R C Indicates the bit rate, A i,j *26 indicates the number of subcarriers contained in one RU, T DFT Indicates the OFDM symbol length, T GI Indicates the symbol interval.

[0214] When the modulation information is determined, the data transmission rate of an RU is related to the number of subcarriers it contains. i,j Calculate the number of optical subcarriers required to transmit the data in the RU and data transfer rates Expressed as: Where ρ is the number of optical subcarriers required for a 26-tone RU capacity; r is the data transmission rate of one optical subcarrier.

[0215] S203-2: For Random RUs used for random access, it is necessary to calculate whether the remaining optical subcarriers are sufficient to carry the data of all Random RUs.

[0216] Calculate the total number of RUs used for random access in all rooms, expressed as:

[0217] Calculate the total number of RUs used for scheduling access in all rooms, expressed as:

[0218] Therefore, the number of optical subcarriers used for random access and scheduled access can be expressed as:

[0219] Assuming that the total number of subcarriers in OFDM-PON is U, if the system has enough subcarriers to meet the requirements of random access RU except for the subcarriers used for special scheduling, that is, Then allocate as needed;

[0220] Otherwise, all remaining optical subcarriers need to be allocated to each SFU according to the expected ratio, which is expressed as: This in turn adjusts the number of 26-tone Random RUs that can be used for random access in the SFU. Calculate the rate of the RU and the rate of the corresponding required optical subcarrier group.

[0221] S204, optical and wireless transmission time:

[0222] S204-1: Synchronous transmission within SFU:

[0223] Due to the synchronization requirements of parallel transmission in the 802.11ax protocol, the data transmitted in parallel must start and end at the same time. If a TS STA reports successfully in the first phase of the SFU, the specific optical and wireless transmission time required for each successful TS STA can be calculated, expressed as:

[0224]

[0225] The transmission duration of the room is taken as the maximum time required for a successful TS STA, which is also set as the transmission duration of Random RUs, expressed as:

[0226]

[0227]

[0228] Among them, T BSR Indicates the time required to transmit the buffer status report frame, T TF Indicates the time required to transmit the trigger frame, T Process Indicates the total processing time of MFU and SFU, T ACK Indicates the time required to confirm a frame, and SIFS indicates the short interframe space.

[0229] If no TS STA reports successfully in the first phase of the SFU, all RUs are used for random access, and the transmission duration of all RUs is set to a fixed value, expressed as: The transmission duration of all optical subcarriers will also be set to a fixed value, expressed as:

[0230] S204-2: Asynchronous between SFUs:

[0231] Reference Figure 6 The figure shows the asynchronous transmission between SFUs. During the transmission process of SFUs with long transmission time, SFUs with a certain transmission time period can perform multiple rounds of transmission. The maximum transmission time of all SFUs is:

[0232] When some SFUs complete the transmission of this round first, they can continue the next round of transmission. After the above scheduling process, the total time T required for the new round can be calculated. i ′, expressed as:

[0233]

[0234] If T i 'Exceeds the maximum remaining time of the previous round The transmission can then be continued according to the estimated time, and after the transmission is completed, it can be determined whether the next round of transmission can be carried out.

[0235] In summary, the service priority-based access protocol of the present invention can increase the probability of users transmitting delay-sensitive services reporting their cache status report frames, thereby allowing subsequent resource allocation algorithms to perform optical and wireless resource allocation based on the obtained status information, giving priority to meeting the needs of delay-sensitive services. The optical and wireless collaborative resource allocation algorithm of the present invention can flexibly allocate RUs of different sizes and corresponding optical subcarriers to users transmitting delay-sensitive services, meeting the different needs of delay-sensitive services; at the same time, it adopts a strategy of synchronization within the room and asynchrony between rooms, allowing multiple rounds of transmission in rooms with short transmission times during transmission in rooms with long transmission times, thereby reducing resource waste caused by zero padding for synchronization alignment.

[0236] To verify the performance of the resource allocation algorithm based on the proposed protocol, a simulation was conducted on Python. In the simulation, the OFDM-PON uplink and downlink rates were 10 Gb / s, and the distance between the optical line terminal (OLT) (i.e., M-FIN) and each optical network unit (ONU) (i.e., S-FIN) was within 100 meters.

[0237] Each room is equipped with an SFU, assuming there is no wireless interference between these SFUs. The wireless distance between the SFU and the STA is within 10 meters. The wireless channel bandwidth of an SFU is 160 MHz, supporting up to 74 26-tone RUs, each supporting a data rate of 11.1 Mbit / s. Each STA generates data frames according to a Poisson distribution, with an arrival rate of 200 frames per second. The data frames received by TS and NTS STAs are 200 bytes and 1500 bytes, respectively.

[0238] During the uplink process, after the Wi-Fi physical layer frame reaches the SFU, it is decapsulated into a MAC frame and then enters the S-FTR through the Ethernet interface. It is first encapsulated into a FEM frame, then encapsulated into a PON MAC frame by the MAC layer, and then further encapsulated into a physical frame and enters the optical link for uplink transmission. The overhead in this process includes the overhead of data frame encapsulation, physical layer forward error correction coding, cyclic prefix, and preamble overhead. The OFDM-PON system is configured with 1024 subcarriers, each with a rate of 9.7 Mbit / s. Considering the aforementioned overhead, two optical subcarriers are sufficient to carry the payload of a single 26-tone RU. During the simulation, four SFUs were set up, and each STA user carried one service, either TS or NTS. The ratio of TS users to the total number of users in each SFU varied randomly between 0.1 and 0.3. The comparison scheme used in the simulation was a service-insensitive access scheme based on trigger frames. The trigger frame of the comparison scheme contains the number and duration of all RUs used for random access. Since the user's buffer status information is not obtained a priori through the BSRP-BSR mechanism, all RUs used for random access are set to the same size, all rooms are fully synchronized, and the same transmission duration is set.

[0239] Figure 7(a) is a schematic diagram of the comparison results of the access delay of the present invention and the comparative solution. As the number of STAs accessing each SFU increases, the access delay of the comparative solution also increases. This is because a large number of STAs competing for access to the wireless channel will cause collisions. The more users compete, the more intense the collisions will be. Transmission failures require waiting for the next round of competition, which affects the access delay of the overall user. The access delay of TS users in all solutions remains basically unchanged and is maintained at a low level below 5ms. Although the delay of NTS users increases with the increase in the number of users in the room, it is still lower than the comparative solution. This is because the proposed priority-based access protocol increases the probability of successful reporting by TS users in the first phase, so that most TS users obtain dedicated resources in the second phase and do not need to compete with other users for access in the second phase. For NTS users, most TS users do not participate in the competition in the second phase, which also increases the probability of some NTS users successfully accessing the channel. The proposed solution also adopts a collaborative resource allocation algorithm, which can dynamically allocate optical and wireless resources of different sizes to TS users based on their different traffic requirements. In addition, it allows rooms with fast transmission speeds to flexibly perform multiple transmissions within a large transmission cycle without having to wait for data from other rooms to be transmitted before transmitting again. This reduces the waiting time for synchronization and lowers access latency. Figure 7 (b) shows a schematic diagram comparing the access jitter of the proposed solution and the comparative solution. Jitter reflects access stability and can be calculated by the mean square error of access delay. The proposed solution exhibits lower access jitter for both service users than the comparative solution, demonstrating its superiority in access delay and jitter. Figure 7 (c) shows a schematic diagram of the comparison results of wireless resource utilization of the present invention and the comparative solution, which is calculated by dividing the bandwidth size of the actual transmitted data by the bandwidth size allocated to the user, where the unutilized part of the resources is the waste of resources caused by the synchronous zero-padding demand transmission of null values.

[0240] In the comparative scheme, since the service type is not distinguished and the traffic requirements of different services are not obtained a priori, the RU resource size and transmission time allocated to all users are fixed, which will result in a large degree of resource waste. This embodiment obtains the traffic requirements of most TS users in the first reporting stage, and dynamically allocates optical and wireless resources to TS users through a collaborative algorithm. There is no need for synchronous waiting between SFUs in different rooms. Asynchronous transmission also improves transmission efficiency and the utilization of resources allocated to TS users, reducing resource waste caused by zero padding. For NTS users, this embodiment fails to obtain their traffic bandwidth requirements, so it allocates fixed-size RUs and transmission times to them, so their resource utilization is similar to that of the comparative scheme. In summary, the present invention reduces the access delay and jitter of users of the two services, and significantly improves the resource utilization of TS users.

[0241] The resource allocation method in the centralized optical and wireless access network described in the present invention only obtains the cache status reports of delay-sensitive users that have successfully reported, and prioritizes the allocation of optical and wireless resources to delay-sensitive users. When delay-sensitive users are prioritized, RUs are initially allocated and reallocated based on the bandwidth requirements of each user, while matching optical subcarriers. By flexibly allocating RUs of different sizes and corresponding optical subcarriers to delay-sensitive users, the different needs of delay-sensitive users are accurately met, greatly improving resource utilization. During the reporting phase, the present invention only allows delay-sensitive (TS) users to report cache status reports. By limiting the competition of non-delay-sensitive (NTS) users, the probability of delay-sensitive users reporting successfully is greatly increased, so that optical and wireless resources can be allocated to delay-sensitive users in the future, effectively reducing the access delay of delay-sensitive users. The present invention adopts a strategy of synchronization within the room and asynchrony between rooms. During the transmission process in the room with a long transmission time, multiple rounds of transmission are allowed in the room with a short transmission time, reducing the resource waste caused by synchronization alignment and zero padding, effectively reducing the access delay and jitter of delay-sensitive services, and significantly improving resource utilization.

[0242] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0243] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0244] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0245] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0246] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for allocating resources in a centralized optical and wireless access network, characterized in that: Applied to every room in the centralized optical and wireless access network, including: Based on the cache status reports of successfully reported TS users, the bandwidth requirements of TS users in the room are obtained, the total wireless transmission capacity and total optical transmission capacity required by TS users in the room are calculated, and the wireless channel width of the room is obtained; Based on the wireless channel width and the ratio of each TS user's bandwidth requirement to the total bandwidth requirement of the room, calculate the expected number of Schedule RUs for each TS user in the room. Based on the expected number of RUs for each TS user and the number of wireless subcarriers in each Schedule RU, obtain the initial number of Schedule RUs allocated to each TS user in the room. Based on the expected number of RUs and the initial number of RUs for each TS user, the scheduled RUs are reallocated to obtain the actual number of RUs for each TS user. Based on the number of wireless subcarriers in each Scheduled RU, obtain the wireless transmission rate corresponding to the TS user; Based on the actual number of RUs for each TS user and the number of radio subcarriers in each scheduled RU, the number of optical subcarriers required to transmit the data of each TS user is calculated. Combined with the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to each TS user is calculated. Calculate the wireless transmission time and optical transmission time of each TS user based on the bandwidth requirements of each TS user and the wireless transmission rate and optical transmission rate corresponding to each TS user; Resources are allocated based on the number of optical subcarriers, wireless transmission time, optical transmission time and preset Random RU transmission duration corresponding to each user.

2. The method for allocating resources in a centralized optical and wireless access network according to claim 1, wherein: Acquisition of cache status reports for successful TS users, including: The MFU sends a buffer status report polling frame to request buffer status reports from all TS users; After receiving the buffer status report polling frame, each TS user obtains the RU information that can be used for random contention access and uses the uplink OFDMA random access mechanism to randomly select an RU to upload the buffer status report: If the RU is selected by only one TS user, the cache status report of the TS user is successful; If the RU is selected by multiple TS users, the cache status reports of the multiple TS users that selected the RU fail to be reported.

3. The method for allocating resources in a centralized optical and wireless access network according to claim 1, wherein: Calculate the total wireless transmission capacity and optical transmission capacity required by TS users in the room, and obtain the room's wireless channel width, including: Based on the total number of supported users in each room , and the bandwidth requirements of TS users in each room, calculate the total wireless transmission capacity required by TS users in each room, expressed as: ； Based on the total wireless transmission capacity required by TS users in all rooms, obtain the minimum available capacity to meet the needs of each room , expressed as: ; Based on the minimum available capacity of all rooms , and the total capacity of the OFDM passive optical network, calculate the total optical transmission capacity required by the TS users in each room , expressed as: ； Adjust the minimum available capacity to meet the needs of TS users in each room ,make ; Based on the minimum available capacity to meet the TS user needs in each room The preset relationship table with the wireless channel width is used to obtain the wireless channel width corresponding to the TS user in each room ; in, Indicates the The total wireless transmission capacity required by TS users in a room, Indicates the Room Bandwidth requirements of TS users and TS STAs, Indicates the The data transmission time of each room in the last round; Indicates the total number of rooms supported in the centralized optical and wireless access network; Indicates the total capacity of OFDM-PON.

4. The method for allocating resources in a centralized optical and wireless access network according to claim 3, wherein: Based on the wireless channel width and the ratio of each TS user's bandwidth requirement to the total bandwidth requirement of the room, calculate the expected number of Schedule RUs for each TS user in the room, expressed as: ； in, Indicates the Room The expected number of RUs of a TS user TS STA, Indicates that the wireless channel width is The total number of RUs supported when Indicates the Room Bandwidth requirements of TS users and TS STAs, Indicates the total number of users supported in each room.

5. The method for allocating resources in a centralized optical and wireless access network according to claim 4, wherein: Based on the expected number of RUs for each TS user and the number of radio subcarriers in each Schedule RU, obtain the initial number of Schedule RUs allocated to each TS user in the room, including: Based on the Room The expected number of RUs for each TS user , calculate the Room RU granularity value for each TS user , expressed as: ; Calculation 2 To get the power Room Initial number of RUs allocated to each TS user , expressed as: .

6. The method for allocating resources in a centralized optical and wireless access network according to claim 5, wherein: Based on the expected number of RUs and the initial number of RUs for each TS user, scheduled RUs are reallocated, including: Based on the wireless channel width and the initial number of RUs for each TS user, the total number of remaining RUs in the room is calculated as: ; Calculate the difference between the expected number of RUs for each TS user and the initial number of RUs to obtain the number of RUs to be satisfied for each TS user, expressed as: ; In each room, sort the number of RUs to be satisfied for all TS users in the room in descending order, and then sort the number of RUs to be satisfied for the TS users in the room in descending order. The total number of remaining RUs in the room For comparison: like , then allocate Scheduled RU to the TS user and update the total number of remaining RUs in the room; like , the demand of this TS user cannot be met, and the number of RUs to be satisfied for the next TS user is compared. The total number of remaining RUs in the room ; The scheduled RUs are redistributed until the total number of remaining RUs in the room reaches 0.

7. The method for allocating resources in a centralized optical and wireless access network according to claim 6, wherein: Based on the number of wireless subcarriers in each scheduled RU, the wireless transmission rate corresponding to the TS user is obtained, which is expressed as: ； in, Indicates the Room Wireless transmission rate of each TS user, represents the number of spatial streams; Indicates the Room The actual number of RUs allocated to each TS user, Indicates the number of subcarriers contained in the RU, Indicates the total number of subcarriers allocated to a TS user; represents the modulation order, Indicates the bit rate; Indicates the OFDM symbol length, Indicates the symbol interval.

8. The method for allocating resources in a centralized optical and wireless access network according to claim 7, wherein: Based on the actual number of RUs for each TS user and the number of radio subcarriers in each scheduled RU, the number of optical subcarriers required to transmit the data of each TS user is calculated. Combined with the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to each TS user is calculated, including: Based on the actual number of RUs for each TS user and the number of radio subcarriers in each scheduled RU, the number of optical subcarriers required to transmit the data of each TS user is calculated as: ； Based on the number of optical subcarriers required to transmit the data of each TS user and the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to each TS user is calculated and expressed as: ； in, Indicates the Room The number of optical subcarriers required by each TS user, Indicates the Room The actual number of RUs allocated to each TS user, Indicates the number of optical subcarriers required to correspond to the capacity provided by the wireless subcarrier of a Scheduled RU. Indicates the Room The optical transmission rate of each TS user, Indicates the transmission rate of a single optical subcarrier.

9. The method for allocating resources in a centralized optical and wireless access network according to claim 8, wherein: Get the preset Random RU transmission duration, including: After the scheduled RU allocation is completed, the number of RUs remaining in the channel is obtained as random RUs and allocated to TS users and NTS users who have not reported successfully. Calculate the number of optical subcarriers, wireless transmission rate, and optical transmission rate required by each user corresponding to the Random RU; Based on each user's bandwidth requirements and the corresponding wireless transmission rate and optical transmission rate, the wireless transmission time and optical transmission time of each user are calculated. Combined with the transmission time of frames in the network, the random RU transmission duration is obtained.

10. The method for allocating resources in a centralized optical and wireless access network according to claim 9, wherein: Calculate the number of optical subcarriers, wireless transmission rate, and optical transmission rate required by each user corresponding to the Random RU, including: Based on the The wireless channel width and the maximum bandwidth of the wireless channel corresponding to the room are calculated. The number of RandomRUs in the room , expressed as: ； Based on the total number of Schedule RUs in all rooms The number of optical subcarriers required for each RU capacity , calculate the total number of optical subcarriers used for scheduling access , expressed as: ； Based on the total number of Random RUs in all rooms The number of optical subcarriers required for each RU capacity , calculate the total number of optical subcarriers used for random access , expressed as: ； Compare whether the number of remaining photocarriers in an orthogonal frequency division multiplexing passive optical network, excluding the photocarriers used for scheduled access, meets the total number of photocarriers used for random access: like , then the remaining optical subcarriers are allocated to users on demand; like , the remaining optical subcarriers are allocated to users in proportion; when allocating in proportion, the number of optical subcarriers allocated to each user is ; Based on the number of radio subcarriers in each Schedule RU, the wireless transmission rate corresponding to the user is obtained. Based on the actual number of RUs for each user and the number of radio subcarriers in each Schedule RU, the number of optical subcarriers required to transmit the data of each user is calculated. Combined with the transmission rate of a single optical subcarrier, the optical transmission rate corresponding to the user is calculated. in, Indicates that the wireless channel width is The total number of RUs supported when Indicates that the wireless channel width is The total number of RUs supported when Indicates the maximum bandwidth of the wireless channel; Indicates the total number of rooms supported in the centralized optical and wireless access network. Indicates the total number of users supported in each room; Indicates the Room The actual number of RUs allocated to each TS user, Indicates the The number of Random RUs used for random access in a room; Indicates the total number of subcarriers in the OFDM passive optical network.

11. The method for allocating resources in a centralized optical and wireless access network according to claim 10, wherein: Based on each user's bandwidth requirements and the corresponding wireless transmission rate and optical transmission rate, the wireless transmission time and optical transmission time for each user are calculated. Combined with the frame transmission time in the network, the Random RU transmission duration is obtained, including: Based on the Room Bandwidth requirements of TS users The corresponding wireless transmission rate , calculate the Room Wireless transmission time of each TS user , expressed as: ; Each Room Bandwidth requirements of TS users The corresponding optical transmission rate , calculate the Room Optical transmission time of a TS user , expressed as: ; Based on the The maximum wireless transmission time of all TS users in the room Maximum optical transmission time , and cache status report transmission time , trigger frame transmission time , processing time , Time required to confirm the frame With short interframe interval , calculate the maximum transmission duration The maximum transmission duration is used as the Random RU transmission duration, which is expressed as: ； in, , .

12. The method for allocating resources in a centralized optical and wireless access network according to claim 11, wherein: After obtaining the number of optical subcarriers, wireless transmission time, optical transmission time, and Random RU transmission duration corresponding to each user, the following is also included: In the same room, enable synchronous transmission between different users; Between different rooms, during the transmission process of users with long transmission time, users with short transmission time are allowed to perform multiple rounds of transmission; The transmission time required for a user with short transmission time to perform a new round of transmission , expressed as: ; like , a new round of transmission cannot be carried out; like , a new round of transmission is carried out and the maximum remaining time is updated ; in, Indicates the maximum transmission time of the user, the expression is ; Indicates the maximum transmission duration.

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