WO2009036693A1 - Method and system for processing uplink and downlink data in wireless communication network - Google Patents

Abstract

A method and a system for processing uplink and downlink data in the wireless communication network are involved. The uplink data processing method includes receiving uplink air interface data, performing channel decoding of the air interface data and encapsulating the valid frames among the decoded air interface data into IP packets. The downlink data processing method includes receiving IP packets and performing channel coding and transmission of the valid frames among the IP packets. The uplink data processing system includes base station transceiver and source decoding unit. The downlink data processing system includes base station transceiver and source coding unit. Encapsulation of data into IP packets enables IP transmission in GSM. The transmission capability of GSM is improved through only transmitting valid frames such as voice frames.

Description

 Method and system for processing upload and downlink data in wireless communication network

 The present invention relates to communication technologies, and in particular, to a method and system for processing transmission data in a Global System for Mobile communication (GSM), and a base transceiver station and a source decoding unit. Background technique

 The existing GSM communication network has two typical network structures, one is a transcoder & Rate Adaptation Unit (TRAU) at the base station controller (Base).

On the side of the Station Controller, BSC), as shown in Figure 1, the TRAU in the base station subsystem 2 serving the mobile terminal 1 is on the BSC side, and the TRAU is not set on the Media Gateway (MGW) 3 side; Switching Center (MSC) / MGW, as shown in Figure 2, the TRAU in the base station subsystem 4 is on the MGW 5 side.

 Both types of voice service data are based on time division multiplexing (Time Division

Multiplexing, TOM) transmission mode, where the voice service data transmission format between each network element is:

 When the TRAU is on the BSC side, the MSC/MGW and the BSC transmit 64Kb it/sec Pulse Code Modulation (PCM) data through the A interface, and the format conforms to the ITU-T standardization by the International Telecommunication Union Telecommunication Standardization Sector (ITU-T). G.711 standard.

 When the TRAU is on the MSC/MGW side, the data format transmitted between the MSC/MGW and the BSC through the Ater interface is the same as the data format between the BTS and the BSC, and the BSC completes data transmission.

 The BTS and BSC transmit TRAU frame data of 16 Kbit/s or 8 Kbit/s through the Abis interface. Among them, the 16Kbit/sec TRAU frame is 40 bytes one frame, and the 8Kbi t/sec TRAU frame is 20 bytes one frame.

The above frame type includes a voice frame for transmitting voice portion data, and a voice gap portion for transmitting data. a silent frame, a bad frame that transmits data that may be corrupted by air interface interference, a null frame or a data frame that is used to fill data, an unreliable frame that may be a bad frame, and the like;

 The wireless air interface data frame format is transmitted between the mobile terminal and the BTS through the Um interface, and the data payload portion of the TRAU frame is carried. Compared with the voice service data, there are voice frames, silence frames, and padding frames. If it is destroyed, it may become a bad frame or an unreliable frame.

 At present, the data transmission in GSM is based on the T-line mode. Since the service frame in the T-style mode occupies a fixed bandwidth, bandwidth sharing cannot be achieved. Summary of the invention

 It is an object of embodiments of the present invention to provide a method for processing transmission data in a wireless communication network to implement IPization of a wireless communication network, thereby implementing bandwidth sharing.

 Another object of embodiments of the present invention is to provide a system for processing transmission data in a wireless communication network to ensure that data in GSM can be transmitted based on IP.

 To achieve the above objective, an embodiment of the present invention provides a method for processing uplink data in a wireless communication network, including:

 Receiving uploaded air interface data;

 Performing channel decoding on the air interface data;

 The valid frame in the decoded air interface data is encapsulated into an IP packet.

 In this embodiment, the received air interface data is encapsulated into an IP packet for transmission, so that the GSM can upload the data by using the IP bearer data.

 To achieve the above objective, an embodiment of the present invention further provides a method for processing downlink data in a wireless communication network, including:

 Receiving a downlink IP packet;

 Channel coding the valid frame in the IP packet;

 The data obtained after the channel coding is transmitted.

In this embodiment, the effective frame in the IP packet is channel-encoded and transmitted, thereby realizing GSM transmits data in IP bearer mode.

 Through the above two schemes, the transmission data in GSM can be IPized, so that GSM transmission data can achieve bandwidth sharing. Moreover, in the above solution, only valid frames such as voice frames and mute frames that are not damaged are processed and transmitted, the band transmission data is reduced, network resources are saved, and the rate of data transmission by GSM is improved.

 In order to achieve the above other object, an embodiment of the present invention provides a system for processing uplink data in a wireless communication network, including a base transceiver station and a source decoding unit, where the base transceiver station receives the received data. The valid frame in the air interface data is encapsulated into an IP packet and sent to the source decoding unit. The source decoding unit decodes the valid frame of the IP packet sent by the base transceiver station, and decodes the decoded data. Encapsulate as an IP packet to continue uploading.

 In this embodiment, the data is encapsulated in the base transceiver station and the source decoding unit, so that GSM can transmit data in IP mode; and only valid frames such as voice frames are transmitted, thereby improving the transmission performance of the GSM.

 In order to achieve the above another object, an embodiment of the present invention further provides a system for processing downlink data in a wireless communication network, including a base transceiver station and a source coding unit, where the source coding unit receives The downlink pulse code modulated speech data is subjected to source coding, and the valid frame in the encoded data is encapsulated into an IP packet and sent to the base transceiver station; the base transceiver station will be from the source coding unit The valid frame of the IP packet is channel coded and sent to the terminal.

 The embodiment of the present invention further provides a base transceiver station, configured to encapsulate a valid frame in the received air interface data into an IP packet, or to receive a valid frame in an IP packet from the source coding unit to perform a channel. coding.

 The embodiment of the present invention further provides a source decoding unit, configured to decode a valid frame in an IP packet from a base transceiver station, and encapsulate the decoded data into an IP packet to continue uploading; or, The received downlink pulse coded modulated voice data is subjected to source coding, and the valid frame in the encoded data is encapsulated into an IP packet and sent to the base transceiver station.

In this embodiment, the data is encapsulated in the base transceiver station and the source coding unit, so that the data is encapsulated. GSM can transmit data in IP mode; and only transmit valid frames such as voice frames, which improves the transmission performance of GSM.

 The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments. DRAWINGS

 Figure 1 is a schematic diagram of a GSM structure;

 Figure 2 is a schematic diagram of another GSM structure;

 3 is a flowchart of Embodiment 1 of a method for processing upload data in a wireless communication network, such as GSM, according to the present invention;

 4 is a flowchart of Embodiment 1 of a method for processing data transmitted in a wireless communication network, such as GSM, according to the present invention;

 5 is a flowchart of Embodiment 2 of a method for processing upload data in a wireless communication network, such as GSM, according to the present invention;

 6 is a flowchart of Embodiment 2 of a method for processing data transmitted in a wireless communication network, such as GSM, according to the present invention;

 7 is a schematic structural diagram of an embodiment of an upload data processing system in a wireless communication network, such as GSM, according to the present invention;

 Figure 8 is a block diagram showing an embodiment of an embodiment of a downlink data processing system in a wireless communication network, such as GSM. detailed description

 Upload method embodiment 1

FIG. 3 is a flowchart of Embodiment 1 of a method for processing data to be uploaded in a wireless communication network, such as a GSM communication network. In this embodiment, the TRAU is set on the BSC side, and after the mobile terminal sends voice data through the Um interface, the air interface is uploaded in the GSM. The voice data in the data specifically includes the following steps: Step 101: The BTS receives the uploaded air interface data from the Um interface. Step 102: Perform channel decoding on the air interface data.

 Step 103: The BTS determines whether the current frame in the decoded air interface data is damaged by the air interface interference, or whether the current frame is an invalid frame such as a bad frame or a padding frame; if yes, step 108 is performed; otherwise, the current frame is a good voice. For a valid frame such as a frame or a mute frame, perform step 104;

 Step 104: The BTS encapsulates the current frame, that is, a valid frame such as a good voice frame or a silence frame, into an IP packet and sends it to the TRAU.

 Step 105, the TSU on the BSC side receives the IP packet, and determines whether the data in the IP packet is an invalid frame such as a bad frame, a null frame, a no data frame, an unreliable frame, etc.; if yes, step 108 is performed; otherwise, step 106 is performed;

 Step 106: After the TRAU decodes the data in the IP packet, the packet is encapsulated into a new IP packet and sent to the MGW.

 Step 107: The MGW receives the IP packet, and sends the data in the IP packet to the core network. In this way, the transmission processing of the uploaded data from the mobile terminal is completed in an IP bearer manner, and the BTS is only valid in the uploaded data. The frame is processed and transmitted, thereby avoiding the transmission processing of useless data in GSM, greatly saving GSM resources and improving the GSM data transmission rate.

 Step 108: Discard the invalid frame. When the TRAU does not receive the valid frame, the smooth PCM data is generated to ensure that the continuous PCM data is transmitted to the core network.

 When the data received by the BTS is enhanced full-rate (EFR) service data or full-rate (FR) service data or half-rate (HR) service data, In order to increase the data upload rate, after receiving the air interface data and performing channel decoding, the BTS can start counting the silence frame when the first silence frame is output, and periodically package the received silence frame into an IP packet for transmission. The strategy of sending a frame of silence frames at a certain interval reduces the transmission of silent frames without affecting the voice quality, thereby further reducing the data that needs to be uploaded, reducing the network load, thereby improving the voice data upload rate and satisfying EFR, FR. Or the needs of the HR business.

 Downstream method embodiment 1

4 is a flow chart of Embodiment 1 of a method for transmitting data in a wireless communication network, such as GSM, according to the present invention In the embodiment, the TRAU is also disposed on the BSC side, corresponding to the first embodiment of the uploading method. The method for transmitting the voice data in the GSM includes the following steps:

 Step 201: The MGW transmits and receives PCM data from the core network.

 Step 202: Encapsulate the PCM data into an IP packet and send the data to the TRAU.

 Step 203: The TRAU performs corresponding source coding on the PCM data, and determines whether the encoded data is a valid frame. If yes, step 204 is performed; otherwise, step 208 is performed;

 Step 204: The TRAU encapsulates the current frame, that is, the valid frame, into an IP packet and sends the packet to the BTS.

 Step 205: The BTS receives data encapsulated by the IP packet from the Abi s interface.

 Step 206: Determine whether the data encapsulated by the IP packet is a valid frame such as a good voice frame or a silence frame, and if yes, go to step 207; otherwise, go to step 208;

 Step 207: Perform channel coding and transmission on the current frame, that is, the effective frame, complete the transmission processing of the PCM data from the core network in the IP bearer manner, and transmit only the effective frame, thereby greatly reducing the burden of the GSM and improving the GSM. Data transfer rate.

 Step 208: Discard the current frame.

 When the PCM data received by the MGW or the TRAU is EFR, FR or HR service data, in order to increase the data downlink rate, when the MGW or TRAU performs the source code output and output the silence frame, the counting is started, and the received silence frame is encapsulated at the timing. Sending IP packets, using a strategy of sending one frame of silence frames at regular intervals, reducing the transmission of silent frames without affecting voice quality, thereby further reducing the data that needs to be transmitted, reducing network load, thereby improving voice. The data downlink rate meets the needs of EFR, FR or HR services.

 Upload method embodiment two

 FIG. 5 is a flowchart of Embodiment 2 of a method for processing an upload data in a wireless communication network, such as GSM. In this embodiment, a TRAU is not set in a BSS, and a TR0 is replaced by a TC in the MGW to minimize the current network. Changes. After the voice data is sent by the mobile terminal through the Um interface, the voice data in the air interface data in the GSM includes the following steps:

Step 301: The BTS receives air interface data from the Um interface, and assumes that the air interface is received in this embodiment. The data is EFR, FR or HR business data;

 Step 302: Perform channel decoding on the air interface data, and determine whether the current frame is damaged by the air interface interference, or whether the current frame is an invalid frame such as a bad frame or a padding frame; if yes, execute step 311; otherwise, the current frame is good. a valid frame such as a voice frame, a silence frame, etc., step 303;

 Step 303: Determine whether the current frame is a silence frame, and if yes, go to step 304; otherwise, go to step 306;

 Step 304: Start counter counting, or determine whether the counter setting time has been reached, for example, send one frame of silence frame every 480 ms, and if yes, go to step 305; otherwise, go to step 312; Step 305, BTS encapsulates the current mute frame as The IP packet is sent to the BSC, and step 307 is performed. Step 306: The BTS encapsulates the current voice frame into an IP packet and sends the packet to the BSC.

 Step 307: The BSC transparently transmits the IP packet to the MGW.

 Step 308: The TC in the MGW receives the IP packet from the Ater interface.

 Step 309, determining whether the data in the IP packet is a valid frame, and if so, executing step 310; otherwise, performing step 313;

 Step 310: Decode the data in the IP packet and send the data to the core network. The uploading of voice data through GSM in GSM is realized.

 Step 311: The TC discards the current invalid frame, and generates smooth PCM data, so as to ensure continuity of PCM data sent to the core network when the received data is an invalid frame, and complete data upload processing;

 Step 312: The BTS discards the current silence frame, does not send data to the BSC, and the BSC does not send data to the MGW. The network load in the GSM is reduced, and the GSM data transmission rate is improved. Then, the TC in the MGW cannot receive the voice payload. In the frame format, smooth PCM data is generated, and continuous PCM data is transmitted to the core network, and the uploading process of data from the mobile terminal in GSM is completed.

 Step 313: The TC discards the data in the IP packet and generates smooth PCM data.

 Downward method embodiment two

6 is a second embodiment of a method for processing downlink data in a wireless communication network, such as GSM, according to the present invention; In the embodiment, the BSS does not set the TRAU in the embodiment, and corresponds to the second embodiment of the uploading method. The method for transmitting the voice data in the GSM includes the following steps:

 Step 401: The TC receives the PCM voice data, where the PCM voice data may be in the G.711 format. Step 402: Perform source coding on the PCM voice data.

 Step 403: Determine whether the current frame outputted by the code is a valid frame, and discard the process if the frame is invalid; if it is a valid frame, further determine whether the PCM voice data is EFR, FR or HR service data, and if yes, execute step 404. Otherwise, go to step 406;

 Step 404: Determine whether the encoded output is a silence frame, and if yes, execute step 405; otherwise, perform step 411;

 Step 405, start counter counting, or determine whether the time set by the counter has been reached, and if yes, go to step 406; otherwise, go to step 411;

 Step 406: The TC encapsulates the current frame into an IP packet and sends the packet to the BSC.

 Step 407: The BSC transparently transmits the IP packet to the BTS.

 Step 408: The BTS receives an IP packet from the Abi s interface.

 Step 409, determining whether the data in the IP packet is a valid frame such as a voice frame, a silence frame, and if so, executing step 410; otherwise, performing step 412;

 Step 410: The BTS sends the current frame, that is, a valid frame such as a voice frame and a silence frame, to perform channel coding and send the channel to the mobile terminal, so that the voice data is transmitted through the IP bearer in the GSM.

 Step 411: The TC discards the current frame, and the current frame is no longer transmitted in the GSM, thereby completing the transmission processing of the downlink data, reducing the network load, and improving the data transmission rate.

 Step 412: The BTS discards the data in the IP packet, which reduces unnecessary network expenditure.

 In a system embodiment, the source codec unit may be replaced by a TC module in the TRAU or MGW. Upload system embodiment

FIG. 7 is a schematic structural diagram of an embodiment of an uplink data processing system in a wireless communication network, such as GSM. In this embodiment, a source decoding unit is implemented by a TRAU module, and the system includes BTS 11, BSC 12, TRAU 13, and MGW. 14 , BTS 11 and the mobile terminal through the Um interface During the data exchange, the BTS 11 receives the air interface data from the Um interface and performs channel decoding. The BTS 11 also has a base station discarding module 15 when the received data is a valid frame such as a voice frame or a silence frame. Then, the BTS 11 encapsulates the valid frames into IP packets and sends them to the TRAU 1 3 . Otherwise, the base station discarding module 15 discards the processing and does not send the uplink. TRAU 1 3 receives the IP packet from the Ab is interface, and the TRAU 1 3 is provided with the decoding discarding module 16. When the data in the received IP packet is a valid frame, the TRAU 13 3 decodes the data in the IP packet. It is then sent to the MGW 14; otherwise, the decoding discarding module 16 discards the invalid frame, and the TRAU 1 3 is no longer processed. The MGW 14 receives the IP packet and sends it to the core network.

 In this embodiment, the BTS 11 may further include a silent frame discarding module. When the air interface data received by the BTS is EFR, FR or HR service data, and the decoded current frame is a silence frame, the BTS sets the counter count. The mute frame discarding module discards other mute frames other than the received mute frame to ensure that the mute frame interval is transmitted, thereby reducing the data to be sent, and improving the rate of GSM uploading and transmitting data to meet EFR, FR or HR services. Demand.

 When the decoding discarding module in this embodiment is replaced with a code discarding module, the TRAU can be used to implement the function of the source encoding unit, and the replaced system becomes a system for processing the downlink data in the GSM communication network. At this time, similarly, the silent frame discarding module can also be set in the TRAU to ensure that the rate of downlink data meets the requirements of the EFR, FR, or HR service.

 Downstream system embodiment

FIG. 8 is a schematic structural diagram of an embodiment of a downlink data processing system in a GSM communication network according to the present invention. In this embodiment, the function of the source coding unit is implemented by a TC module in the MGW. The system includes: a BTS 21, a BSC 22, and an MGW 23; the BTS 21 further includes a base station discarding module 24, and when the data is downlinked, the TC module 25 in the MGW 23 receives the G.711 format PCM voice data, and performs corresponding sources. Encoding processing; when the encoded output data is a valid frame, the TC module 25 encapsulates the encoded output data into an IP packet, which is sent by the MGW 23 to the BSC 22; otherwise, the encoding discarding module 26 discards the data without transmitting. The BSC 22 transparently transmits the received IP packet to the BTS 21; the BTS 21 receives the IP packet from the Abis interface, and when the received data is a valid frame, the BTS 21 enters the received data. Line channel coding, and send valid frames to the mobile terminal through the Um interface, otherwise the base station discards the module

24 discarding these data, BTS 21 does not perform coding, downlink, etc., which greatly saves network resources and improves the transmission rate.

 In this embodiment, the TC module 25 may also include a silent frame discarding module. When the PCM data received by the TC module 25 is EFR, FR or HR service data, and if the encoded current frame is a silence frame, then the TC The module 25 sets the counter count, and the silent frame discarding module discards the other silence frames other than the received silence frame to ensure that the silent frame interval is transmitted, thereby reducing the data to be transmitted and improving the rate of the GSM downlink data to meet the EFR. , FR or HR business needs.

 When the code discarding module 26 in this embodiment is replaced with a decode discarding module, and the TC module 25 implements the function of the source decoding unit, the system of the present embodiment becomes a system for processing upload data in the GSM communication network. When uploading data, the BTS 21 receives the air interface data from the Um interface and performs channel decoding. When the decoded data is a valid frame such as a good speech frame or a silence frame, the BTS 21 encapsulates the decoded data into an IP packet. Sent to the BSC 22, otherwise, the base station discarding module 24 discards the received data; the BSC 22 transparently transmits the IP packet to the MGW 23; the TC module 25 in the MGW 23 receives the IP packet encapsulated voice data from the Ater port; When the data received by the module 25 is a valid frame such as a good speech frame or a silence frame, the TC module 25 performs source coding on the received data and transmits it through the MGW 23; otherwise, the decoding discarding module discards the received data. The MGW 23 also does not upload these data, at which point the TC module 25 generates smooth PCM data to ensure continuity of the PCM data transmitted to the core network.

 Similarly, a silent frame discarding module can be set in the BTS 21 to ensure that the rate of uploading data meets the requirements of EFR, FR or HR services.

The above method embodiment encapsulates the received data into an IP packet, realizes IP transmission in GSM, thereby enabling bandwidth sharing; and transmitting only valid frames, reducing the amount of data that GSM needs to transmit, thereby reducing GSM. The pressure increases the transmission rate of GSM. For EFR, FR or HR service data, the silence frame is transmitted at intervals according to the rate requirement, which further reduces the network load and improves the transmission rate. The above system embodiment performs IP encapsulation on BTS, TRAU, and TC. The GSM can transmit data in IP mode; according to the judgment result of the judging module, only the effective frame is transmitted, the GSM data transmission performance is further improved, and the requirements of the EFR, FR and HR services are satisfied.

 A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The steps of the foregoing method embodiments are included; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

 It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced. The modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

Rights request A method for processing an upload data in a wireless communication network, comprising: receiving an uploaded air interface data;  Performing channel decoding on the air interface data;  The valid frame in the decoded air interface data is encapsulated into an IP packet.  2. The method according to claim 1, further comprising:  The invalid frame in the decoded air interface data is discarded.  The method according to claim 1, wherein the encapsulating the valid frame in the decoded air interface data into an IP packet comprises:  The voice frame in the valid frame is encapsulated into an IP packet, and/or the silence frame in the valid frame is encapsulated into an IP packet.  The method according to claim 3, wherein the encapsulating the silence frame in the valid frame as an IP packet comprises:  The silent frame in the valid frame is periodically encapsulated into an IP packet, and the silent frame that is not encapsulated into an IP packet is discarded.  The method according to any one of claims 1-4, wherein after the encapsulating the valid frame in the decoded air interface data as an IP packet, the method further includes:  Decoding the valid frame in the IP packet and continuing to upload; or  The valid frame in the IP packet is decoded by the source and the valid frame decoded by the source is encapsulated into a new IP packet and the upload is continued.  The method according to claim 5, further comprising: generating smooth pulse code modulated data when the data decoded by the source source is an invalid frame or the data in the IP packet is an invalid frame . A method for processing downlink data in a wireless communication network, comprising: receiving a downlink IP packet; Channel coding the valid frame in the IP packet;  The data obtained after the channel coding is transmitted.  The method according to claim 7, wherein the receiving the IP packet further includes a process of generating an IP packet, where the process of generating an IP packet includes:  Receiving pulse code modulated data;  Performing source coding on the pulse code modulated data;  The valid frame in the source encoded data is encapsulated into an IP packet.  The method according to claim 8, wherein after the encoding the pulse coded modulated data by the source, the method comprises:  Discard invalid frames in the source encoded data.  The method according to claim 8, wherein the valid frame in the data encoded by the source is encapsulated into an IP packet, including:  The voice frame in the valid frame is encapsulated into an IP packet, and/or the silence frame in the valid frame is encapsulated into an IP packet.  The method according to claim 10, wherein the mute frame in the valid frame is encapsulated into an IP packet, including:  The silent frame in the valid frame is periodically encapsulated into an IP packet, and the silent frame that is not encapsulated into an IP packet is discarded.  The method according to any one of claims 7 to 11, wherein before the channel coding of the valid frame in the IP packet, the method further includes:  When the data in the IP packet is an invalid frame, the invalid frame in the IP packet is discarded.  13. A system for processing upload data in a wireless communication network, comprising a base transceiver station and a source decoding unit, wherein:  The base transceiver station encapsulates the valid frame in the received air interface data into an IP packet, and sends the signal to the source decoding unit. The source decoding unit sends a valid frame in an IP packet sent by the base transceiver station Source decoding, encapsulating the decoded data into an IP packet to continue uploading.  The system according to claim 13, wherein the base transceiver station further comprises a base station discarding module, configured to discard invalid frames in data received by the base transceiver station.  The system according to claim 13 or 14, wherein the source decoding unit further comprises a decoding discarding module for discarding invalid frames received by the source decoding unit.  The system according to claim 13 or 14, wherein the base transceiver station further comprises a silent frame discarding module, configured to discard a silent frame that is not encapsulated into an IP packet by the base transceiver station. .  17. A system for processing downlink data in a wireless communication network, comprising a base transceiver station and a source coding unit, wherein:  The source coding unit performs source coding on the received downlink pulse code modulated voice data, and encapsulates the valid frame in the encoded data into an IP packet and sends the signal to the base transceiver station;  The base transceiver station channel-encodes the valid frame from the IP packet of the source coding unit and transmits it to the terminal.  18. The system of claim 17, wherein the base transceiver station further comprises a base station discarding module for discarding invalid frames in data received by the base transceiver station.  The system according to claim 17 or 18, wherein the source coding unit further comprises an code discarding module for discarding invalid frames in the data received by the source coding unit.  The system according to claim 17 or 18, wherein the source coding unit further comprises a silence frame discarding module, configured to discard a silence frame that is not encapsulated into an IP packet by the source coding unit. .  21. A base transceiver station, characterized by:  The base transceiver station is configured to encapsulate the valid frame in the received air interface data into an IP packet; or The base transceiver station is configured to receive a valid frame from an IP packet of a source coding unit Line channel coding.  22. The base transceiver station of claim 21, wherein:  The base transceiver station further includes a base station discarding module, the base station discarding module for discarding invalid frames in the data received by the base transceiver station.  23. A source decoding unit, characterized by:  The source decoding unit is configured to perform source decoding on the valid frame in the IP packet from the base transceiver station, and encapsulate the decoded data into an IP packet to continue uploading; or  The source coding unit is configured to perform source coding on the received downlink pulse coded modulated voice data, and encapsulate the valid frame in the encoded data into an IP packet and send the signal to the base transceiver station.  24. The source decoding unit of claim 23, wherein:  The source coding unit further includes a silence frame discarding module, and the silence frame discarding module is configured to discard a silence frame that is not encapsulated into an IP packet by the source coding unit.