CN1292621C - A method for selecting transmission format combination in mobile communication system - Google Patents

Abstract

A method for selecting a transmission format combination in a mobile communication system. Before data transmission, the transmission format combination set is configured according to the relevant attributes of the transmission channel; the transmission format combination set is sorted according to the priority of the transmission channel and the amount of data supported by each transmission channel transmission format. ;In data transmission, before selecting the combination of transmission formats for each transmission, the logical channels are first traversed in units of transmission channels, the data volume information of the transmission channels is obtained, and the transmission channels are sorted according to the priority; the transmission is selected according to the data volume of the channel format combination. By simplifying the configuration of the transmission format combination set, when selecting the transmission format combination, the transmission channels with different priorities are jointly selected, so that the transmission format combination can be processed efficiently.

Description

A Selection Method of Transmission Format Combination in Mobile Communication System

technical field

The invention proposes a method for selecting a combination of transmission formats when multiple services are transmitted concurrently in a mobile communication system.

Background technique

In the 3G mobile communication system, the development of communication technology and the improvement of user requirements make it possible and necessary to transmit multiple services concurrently. For example, a terminal user may need to transmit multiple data, voice and other service streams at the same time.

In the system, various business data exist in the logical channel in the form of Protocol Data Unit (PDU) of a specific size, and are aggregated to the transmission channel in a certain way. Each transmission channel has a set of transmission formats ( Transport Format is abbreviated as TF, and a group of TFs is called a transmission format set: Transport Format Set is abbreviated as TFS), which contains the transmission format information supported by the transmission channel, such as transmission block size, transmission time interval, etc., during transmission, The data in the transmission channel must be organized according to the transmission format in order to be parsed correctly.

Different logical channels carry data streams of different services, have different requirements for transmission, and thus have different priorities. Correspondingly, transmission channels also have different priorities. A specific logical channel is mapped to a specific transport channel according to classification methods such as priority and function. The data volume, quantity, and priority of the logical channel must be considered when weighing the transmission format of the corresponding transmission channel.

Each transport channel finally determines a transport format combination (TransportFormat Combination abbreviated as TFC) to be multiplexed on the physical channel according to certain principles, and sent to the peer layer of the receiver in the form of frames (or time slots). The frame decodes the correct business data. Therefore, the system must agree on a set of Transport Format Combination Set (Transport Format Combination Set abbreviated as TFCS) at the sending and receiving ends, so that the data of each transmission channel can be combined into frames at the sending end in a way that can be recognized by both parties, and can be transmitted at the receiving end. ends correctly disassembled. During transmission, for each data frame, there is a Transport Format Combination Indicator (Transport Format Combination Indicator abbreviated as TFCI) to indicate the selected TFC.

The physical channel is based on transmission power and related conditions, and there are corresponding restrictions on the total data flow of the transmission channel multiplexed into the physical channel. Therefore, a transport channel can support multiple transport formats, but the combination of the transport formats when multiple transport channels are combined is not arbitrary. Generally, the allowed TFCS is the full combination of each TF supported by each transport channel after removing TFCs whose data volume is too large to be carried by the physical layer.

Specifically (but not necessarily), for the TD-SCDMA mobile communication system, the implementation process is:

On the UE (User Equipment) side and the RNC (Radio Network Controller) side, the communication parties agree on a set of TFCS at the beginning of the service.

During the transmission process, at each transmission time interval (Transmission Timing Interval abbreviated as TTI), various data are processed by the radio link layer (Radio Link Control abbreviated as RLC), and exist in the logical channel in the form of data flow. The media access layer (Medium Access Control is abbreviated as MAC) counts the amount of data multiplexed to the logical channel of each transmission channel, taking into account the relationship between the priority of the logical channel and the priority of the transmission channel, and dynamically selects the appropriate transmission of each transmission channel in TFCS format, according to the selected transmission format, the logical channel data is multiplexed and packaged into a transmission channel PDU, and stored in the transmission channel. Finally, it is sent out through the physical layer.

In the above process, firstly, the protocol restricts the transmission power for the selection of effective TFCS, but even under this limitation, TFCS is a rather large data set, and there are problems of low efficiency in maintenance and search, and Not all TFCs can be selected equally, and the TFCS can be streamlined through a certain solution to improve system efficiency. Secondly, the relevant protocols of relevant standards do not standardize how to select the transmission format. The US patents "Wireless network with a selection of transport format combinations" (public number 20020085531) and "Wireless network having a selection of transport format combinations" (public number 20020097695 ) proposed a solution (the former focuses on principles, the latter focuses on implementation methods), but the main feature of the solution is that each transmission channel is independent of each other when selecting TFC. The premise of this is that the selected TFCS must be each transmission channel Part (or all) of the channel supports the full combination of TFs, and each TFC in the full combination must meet the power limit. The disadvantage is that the given TFCS still has redundancy, and the physical channel cannot be effectively used. However, the method proposed in the Chinese patent "Data Transmission of Telecommunication Networks" (publication number CN1385050A) using weighting factors and tracking counts to realize TFC selection is more complicated and has the same disadvantages in TFCS configuration.

Contents of the invention

The technical problem to be solved by the present invention is to propose a TFC selection method during multi-service combined transmission in view of the defects of the above-mentioned prior art, which can quickly and efficiently determine according to the instantaneous source rate of the data source under the premise of complying with the protocol. How data streams are combined.

Technical scheme of the present invention is:

1.1 Before data transmission, configure the Transport Format Combination Set (TFCS) according to the relevant attributes of the transmission channel. The specific method can be: according to the different data types carried by each transmission channel, the typical data flow of each transmission channel obtained in statistics and other information, extract the appropriate TFCS subset from the full combination of TFS of all transport channels.

1.2 Sort the transport format combination set (TFCS) according to the priority of the transport channel and the amount of data supported by each transport channel transport format (TF);

1.3 In data transmission, before selecting the Transport Format Combination (TFC) for each transmission, the logical channels are first traversed in units of transmission channels, the data volume information of the transmission channels is obtained, and the transmission channels are sorted according to priority;

1.4 Select the transmission format combination according to the data volume of the channel.

The method of sorting the transport format combination set in step 1.2 is: design the transport format combination set table, each column represents a transport channel, and each row represents a transport format combination (TFC); the transport channel has high priority first, and low priority The transmission format (TF) of the highest priority transmission channel comes first, and the transmission format (TF) of small data volume follows; the transmission format (TF) of the lower priority is according to the previous priority Transport format (TF) grouping, in each group, the transport format (TF) with large data volume comes first, and the transport format (TF) with small data volume follows.

Step 1.4 is: according to the order from high priority to low priority, and according to the transmission channel data of high priority as much as possible, and taking into account the principle of data transmission of low priority transport channel, from the transport format combination set (TFCS) The Transport Format Combination (TFC) is selected by selecting the Transport Format (TF) for each transport channel in . Specifically, when a transport format (TF) is selected for a high-priority channel, it is necessary to verify whether the low-priority channel has an allowed transport format (TF) to choose from, that is, there must be at least one transport format (TF) for the corresponding channel. TF, so that the data in the channel can fill up the amount of data required by this TF. The TF of the high-priority channel is determined only when it is sure that all low-priority channels have corresponding TFs to choose from, otherwise, the high-priority channel can only give up this TF and select the second TF;) When selecting the second highest priority At the same level, the same verification needs to be done until a TF that can transmit as much data as possible for high-priority channels is found, and a TF that can correspond to low-priority channels is found.

By simplifying the configuration of the TFCS, the present invention jointly selects transmission channels with different priorities when selecting TFCs, and can process TFCs efficiently.

Description of drawings

Fig. 1 is the realization flowchart of the present invention.

Detailed ways

Referring to Fig. 1, in (1), the TFCS is configured, and the TFCS should predict the typical data traffic distribution according to the properties and applications of the transmission channel, and select the appropriate TFCS from the full combination of all TFs in each transmission channel;

In (2) and (3), the TFCS and transport channels are sorted after the configuration is completed, thereby simplifying the processing in each TTI;

(5), (6), (7) in the figure are the concrete steps of (4). In the process of data transmission, in each TTI, three processes of step (5), step (6) and step (7) need to be completed, so as to complete the data transmission of the transmission channel.

The following TFC options are described in detail:

Table I): TrCH1 TrCH2 TrCH3 ... TrCH ... ... ... ... ... ... TFC(n) TF1 TF1 TF1 ... TF2 TFC(n+1) TF1 TF1 TF2 ... TF1 ... TF1 TF1 TF2 ... TF2 ... TF1 TF1 TF2 ... TF3 ... TF1 TF2 TF1 ... ... ... TF1 TF2 TF1 ... ... ... TF2 TF1 TF1 ... ... ... TF2 TF1 TF2 ... ... ... TF2 TF1 TF2 ... ... ... ... ... ... ... ...

The configured TFCS table is a two-dimensional table related to the transmission channel and the transmission channel TF, as shown in Table (1) (sorted), in the table, each column represents a transmission channel, each row represents a TFC, and the sorting method Yes: the high priority of the transmission channel is first, and the low priority is last; the highest priority transmission channel is the TF with large data volume, and the TF with small data volume is sorted last, and the low priority TF is grouped according to the previous priority In each group, TF with large amount of data comes first, and TF with small amount of data follows.

When selecting a TF with the highest priority, a definite TFC is not actually selected, but only a subset of TFCS is defined. Because TFCS is a combination of the TFS of each transport channel, so in a TFCS, the TF of a transport channel must appear multiple times. For example, notice that in Table (1), the transport format TF1 of the transport channel TrCH1 in the sorted TFCS is It happened many times. In this way, the TF that selects a transmission channel cannot uniquely determine a TFC, but only limits a range. As shown in Table (2).

The selection of secondary priority is similar, as shown in Table (3).

During the selection process, the selection may be unsuccessful. For example, as shown in the light gray shade in the third row of Table (4), the data volume of the transmission channel is under the premise that TrCH1 and TrCH2 meet the selected TF, but TrCH3 cannot satisfy it. When the light gray TFC fails to be selected, then select the fourth, fifth and sixth lines shown in dark gray.

Table II):

Table (3):

Table (4):

Table (5):

Generally, a TFC cannot be finally determined until the transmission channel with the lowest priority is gradually selected, as shown in Table (5).

In the following, the MAC-d data downlink DCH at the RNC side of the TD-SCDMA system is taken as an example for illustration. The present invention can handle similar data transmission processing.

Assume that there are 4 DCHs, and their priorities are DCH1, DCH2, DCH3, and DCH4 from high to low. The corresponding supported TFSs are sorted according to the amount of data allowed to be transmitted:

DCH1: {TF1=3, TF2=2, TF3=0}

DCH2: {TF1=3, TF2=1, TF3=0}

DCH3: {TF1=2, TF2=0}

DCH4: {TF1=1, TF2=0}

Before data transmission, configure the TFCS of MAC-d as:

TFC1: {TF1(DCH1), TF2(DCH2), TF2(DCH3), TF1(DCH4)}

TFC2: {TF2, TF3, TF1, TF2}

TFC3: {TF2, TF3, TF2, TF1}

TFC4: {TF3, TF3, TF2, TF2}

Assuming that in a certain transmission, the data volume of each transmission channel is {3, 1, 0, 1}, the following judgment process is performed when selecting TFC:

First, select DCH1 tentatively. In TFCS, the TF corresponding to the maximum data transmission of DCH1 is TF1, so it is assumed that TF1 is selected, and DCH2 is tentatively selected;

When testing DCH2, on the premise that DCH1 selects TF1, the subset that DCH2 can select is only TFC1. In this subset, DCH2 can only select TF2. Fortunately, TF2 just meets the transmission requirements of the transmission channel. Assuming that TF2 is selected, the DCH3 conducts a test;

The test of DCH3 is the same as that of DCH2;

Test DCH4 and find that TFC1 can meet the transmission requirements, so the test is successful and selected.

Assuming that in a certain transmission, the data volume of each transmission channel is {3, 1, 2, 2}, the following judgment process is performed when selecting TFC:

According to the traversal principle from high priority to low priority, high data volume to low data volume, TFC1 is selected first. In this case, the TF selected by DCH1 and DCH2 can just send the data in the channel, while for DCH3 As far as DCH4 is concerned, the amount of data can also meet the minimum requirements for sending, that is, there is enough data in the channel to fill the selected TF, although DCH3 will retain two units of data, while DCH4 will retain one unit of data. Therefore, in this transmission, TFC1 is selected.

In the above example, the data is sent just right. In this example, the selection method is the same as the above example, but the data is delayed.

Assuming that in a certain transmission, the data volume of each transmission channel is {3, 0, 2, 0}, the following judgment process is performed when selecting TFC:

First, select DCH1 tentatively. In TFCS, the TF corresponding to the maximum data transmission of DCH1 is TF1, so it is assumed that TF1 is selected, and DCH2 is tentatively selected;

When testing DCH2, on the premise that DCH1 selects TF1, the subset that DCH2 can select is only TFC1. In this subset, DCH2 can only select TF2, but the amount of data in the channel is 0, which cannot fill TF2, so If this test is unsuccessful, return to the test on DCH1;

For DCH1, select the secondary data transmission amount TF as TF2, assuming that TF2 is selected, and test DCH2;

At this time, the TFCS limited by the assumption of DCH1 is {TFC2, TFC3}, and the only TF available for DCH2 is TF3, and it is assumed that TF3 is selected;

At this time, the optional TFCS of DCH3 is still {TFC2, TFC3}, and the optional TFs of DCH3 are {TF1, TF2}, first select TF1, and test DCH4;

At this time, DCH4 can only select TF2, which meets the transmission requirements and is selected. The corresponding TFC is TFC2.

Claims (3)

1. A method for selecting a transmission format combination in a mobile communication system, comprising: 1.1 Before data transmission, configure the transmission format combination set according to the data type carried by the transmission channel and the typical data traffic of each transmission channel obtained in statistics; 1.2 Sort the transmission format combination set according to the transmission channel priority and the data volume supported by each transmission channel transmission format; 1.3 Traversing logical channels in units of transmission channels, obtaining data volume information of transmission channels, and sorting transmission channels according to priority; 1.4 According to the order of channel priority from high priority to low priority, and according to the principle of transmitting data of high priority transmission channels as much as possible, and taking into account the principle of data transmission of low priority transmission channels, select each transmission format from the transmission format combination set The transport format of the channel, thereby selecting the transport format combination. 2. The method for selecting a transmission format combination in a mobile communication system according to claim 1, wherein the method of sorting the transmission format combination set in step 1.2 is: designing a transmission format combination set table, each column representing a transmission format Channel, each line represents a transmission format combination; the transmission channel with high priority comes first, and the low priority follows; the highest priority transmission channel has a large data volume transmission format before, and the small data volume transmission format follows; low priority transmission format The transmission formats of the previous priority are grouped, and in each group, the transmission format with large data volume is in front, and the transmission format with small data volume is in the back. 3. The method for selecting a transmission format combination in a mobile communication system according to claim 1, wherein when a transmission format is selected for a high-priority channel, it is necessary to verify whether the low-priority channel has an allowed transmission format for use Select, if there is, the high priority channel is determined, otherwise, the second highest priority is selected.

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